Crossing New Frontiers

INTAV International Field Conference on Tephrochronology “Tephra Hunt in Transylvania” Moieciu de Sus, Romania,

24 June - 1 July 2018

INTAV-RO

Crossing New Frontiers

INTAV International Field Conference on Tephrochronology “Tephra Hunt in Transylvania” Moieciu de Sus, Romania, 24 June - 1 July 2018

Book of Abstracts

Ulrich Hambach & Daniel Veres (eds.)

Stefan Holzeu (BayCONF system administrator)

The “Crossing New Frontiers - INTAV International Field Conference on Tephrochronology “Tephra Hunt in Transylvania” is taking place between 24 June - 1 July 2018 at Cheile Gradistei Resort Fundata, Moieciu de Sus, Romania. The host of the meeting is the Romanian Academy through the Institute of Speleology, and the Bayreuth Center of Ecology and Environmental Research (BayCEER).

The local organizing committee:

- Daniel Veres - Institute of Speleology, Romanian Academy, Cluj-Napoca, Romania - Ulrich Hambach - BayCEER, University of Bayreuth, Bayreuth, Germany - David Karátson - Eötvös Lorand University, Budapest, Hungary - Ioan Seghedi - Institute of Geodynamics, Romanian Academy, Bucharest, Romania - Alida Timar-Gabor - Babes-Bolyai University, Cluj-Napoca, Romania - Alexandru Szakács - Institute of Geodynamics, Romanian Academy, Bucharest, Romania - Cristian Panaiotu - University of Bucharest, Bucharest, Romania

INTAV-RO: http://www.bayceer.uni-bayreuth.de/intav2018/

The INTAV executive:

- Britta Jensen, University of Alberta, Canada - Peter Abbott, University of Bern, Switzerland - Takehiko Suzuki, Tokyo Metropolitan University, Japan - Siwan Davies, Swansea University, United Kingdom - David Lowe, University of Waikato, New Zealand

INTAV website: http://www.comp.tmu.ac.jp/tephra/intavtmu/top.html Facebook: http://www.facebook.com/groups/INTAV/

Layout: University of Bayreuth, BayCEER, 95440 Bayreuth, Germany (BayCONF system, Stefan Holzheu) Editors: Dr. Ulrich Hambach; Dr. Daniel Veres Print: Daisler Print House, Cluj-Napoca, Romania Front cover picture: Ciomadul lava dome complex, Romania (photo David Karátson) Back cover picture: Volcano-shaped structure caused by the eruption of mud and natural gases at Paclele Mici, Buzau area, Romania (photo Daniel Veres)

Table of Contents

Foreword...... 1

Programme...... 6

List of Posters...... 11

Evening Lecture...... 16

Keynotes...... 17

Oral Presentations...... 27

Oral Session 1...... 27 Oral Session 2...... 32 Oral Session 3...... 37 Oral Session 4...... 45 Oral Session 5...... 55 Oral Session 6...... 61 Oral Session 7...... 67 Posters...... 73

Poster Session 1...... 73 Poster Session 2...... 88 Poster Session 3...... 106 List of Participants...... 124

List of Authors...... 128

1

Foreword: Crossing New Frontiers

The local organising committee (LOC), together with members of the executive committee of the International Focus Group on Tephrochronology and Volcanism (INTAV), warmly welcome you to this international field conference on tephrochronology, “Tephra Hunt in Transylvania”, set in the wonderful landscapes of the south Carpathian Mountains in Moieciu de Sus, Romania, from 24 June to 1 July, 2018. We are pleased and inspired to see so many here – thank you all for coming.

The central theme for the conference, “Crossing New Frontiers”, was chosen for a number of reasons. Firstly, we wanted to bring participants with a strong interest in tephra studies to a region in central-eastern Europe, somewhat off the beaten track but with much to offer, and to see a most interesting array of proximal (local) volcanic and pyroclastic deposits (e.g., Karátson et al., 2017) as well as distal tephras derived from beyond Romania, typically preserved in extensive loess deposits. Ultra-distal cryptotephra deposits from Iceland have recently been discovered in the area as well (Kearney et al., 2018). Secondly, we were keen to encourage both established and emerging generations of tephrochronologists to come together from many countries, crossing many borders to get to Romania, to help support one another, to experience and learn from multiple points of view, and to network. Thirdly, the remarkable rise of modern, systematic cryptotephra studies (e.g., Davies, 2015; Lane et al., 2017), kicked off by the seminal paper published in 1989 by Andrew Dugmore (Dugmore, 1989), has seen new techniques and applications emerging within the science of tephrochronology to cater for the demanding, forensic-like requirements of cryptotephra studies, such as the development of new protocols for the efficacious analysis of glass microshards and growing applications of new technologies including ITRAX core scanning and medical CT imaging. These techniques are also useful for studies on visible tephras. The conference thus provides the perfect opportunity to showcase the exciting advances being made in the discipline of tephrochronology by crossing new frontiers in knowledge and understanding. Fourthly, the conference follows a succession of international meetings focussed on tephrochronology that stretches back nearly 60 years to 1961 when a group comprising Masao Minato, Kunio Kobayashi, and Sohei Kaizuka of Japan made the successful proposal to establish the first ‘Commission on Tephrochronology’ (COT) at the INQUA Congress in Warsaw, Poland, in September 1961, initially led by Prof. Kobayashi (Kobayashi, 1965). Our meeting in Romania thus crosses the frontiers of time by building on the work of those who have gone before and the realisation that the most effective study of tephras requires a collective and global approach. Finally, one of the joys of science, and tephrochronology and volcanic studies in particular, is the opportunity to meet like-minded colleagues and keen students in the field where formalities and reserve seem to dissipate in the face of shared interests, friendly discussions at the outcrop, and in meeting new people and cultures whilst being graciously hosted in new countries.

This week’s conference has its origins with an email sent to David Lowe on 3 October 2016 in which Daniel Veres asked if INTAV, through the EXTRAS project, would be interested in supporting a two-day meeting in Romania or Serbia in 2017 “focusing on tephra as chronostratigraphic markers in loess”. Daniel wrote: “We have fantastic loess records there along the Danube, studied at really high-resolution and we found also many tephra layers – beside the widespread CI/Y5 tephra, for most of the rest there are serious issues in getting reliable chemical data (due to alteration mainly). Thus, I am thinking of a dedicated workshop in which we could actually set out protocols that could be employed successfully in providing reliable marker horizons for loess records that would allow direct comparisons with marine records nearby”. The INTAV committee had, coincidently, scheduled a Skype session about 24 hours later to discuss possible venues for an international tephra meeting, very aware that more than six years had elapsed since the memorable tephra meeting held in Kirishima in southern Japan in May, 2010. Daniel was swiftly asked if he would consider convening a full tephra meeting in Romania in 2018, rather than in 2017, to allow more time for it to be well organised, to garner as much support as possible from the global tephra community including emphasis on early career researchers and students, and to try to raise financial backing for the event.

Much water has flowed under the bridge since then, but the outcome of that portentous October email is now upon us: a week-long conference in a stunning venue where tephrochronology and volcanology will feature in an exhilarating programme of 42 oral papers, 53 poster papers, seven invited keynote papers, and a special evening public lecture introducing us to the local geology and volcanism and its products (i.e., 103 presentations in all). In addition to a hands-on Bayesian age- 2 modelling workshop, and in keeping with the long tradition of inter-INQUA conferences having a central field component, we look forward also to four days in the field on excursions that offer something for everyone: a one-day mid-conference trip, available for all participants, and a three-day post-conference trip (for which around 32 participants have signed up). Oral presentations will be 15 minutes in duration, with 12 minutes for speaking and 3 minutes for discussion. Keynote presentations are 30 minutes in total duration. Following the COT-INTAV tradition, only one session of oral papers is being run so that participants can take in all the talks. In addition, we have placed equal value on poster papers, with all posters being displayed for the entirety of the conference; presenters have been scheduled for one of three poster sessions so that they can also see and discuss posters other than their own during the other sessions.

Of course, presenting the papers is only half the journey: we are pleased to advise that there has been strong support for a tephra-focussed special volume of papers from the meeting to be published in Quaternary International. Previous conferences have generated such volumes, with papers from the Kirishima meeting in Lowe et al. (2011) being among the most-downloaded and highly-regarded for the journal. As well as gaining enhanced exposure for the papers by publishing in a collective tephra volume, the royalties from Quaternary International (owned by INQUA) are ploughed back into the Quaternary community through grants to projects or associated events, such as for this conference, and for the skills-based workshop held in Portland, USA, in August 2017. More information about the process of submitting a paper to the special volume, and the names of the guest editors, will be provided during the conference. It is likely that the deadline for the submission of papers will be 31 December 2018.

At the time of writing, 94 participants have registered for the meeting, representing 21 countries, and including 22 students (17 undertaking PhDs). This number of participants is a record, the previous high being 74 participants at Kirishima in 2010. The greatest numbers are from the UK (24), Germany (14), Romania (7) and the USA (5) with up to four representatives from each of Denmark, Russia, Norway, Sweden, Canada, Italy, Switzerland, Turkey, Japan, China, Poland, India, Serbia, Hungary, Singapore, Iceland, and New Zealand. We are especially grateful to the seven keynote speakers who have come from far and wide to provide cornerstone presentations for each of the seven oral sessions: Sabine Wulf (UK), Michael Sigl (Switzerland), David Karátson (Hungary), Caroline Bouvet de la Maisonneuve (Singapore), Maarten Blaauw (UK), John Westgate (Canada), and Vera Ponomareva (Russia). Maarten is kindly running the age-modelling workshop as well as giving his keynote paper. We unapologetically single out John Westgate for special mention and thanks. John has been involved with COT (now INTAV) since 1965 in multiple roles, including publishing the first global bibliography on tephrochronology that had its roots in a COT meeting in Tokyo, 1964 (Westgate and Gold, 1974), and he helped revitalise COT by forming and leading the Inter-Congress Committee on Tephrochronology from 1987 to 1991 (see Froese et al., 2008). In 1969 John published the first paper (with D.G.W. Smith) documenting how the analysis of glass by the electron microprobe could be used to characterise tephras, using as few as three elements/oxides, to facilitate their correlation over long distances in northwestern North America ‒ a paper we think worthy of commemoration fifty years later. Steve Kuehn is thanked for his catalytic role in discussions around the ongoing development of a global database for tephra studies, an activity he has been working towards for some years now on behalf of INTAV and EXTRAS including at the INTAV- IAVCEI workshop held in Portland last year.

Our gratitude extends also to Daniel Veres for agreeing to undertake the very substantial work and responsibility required to convene the conference, and to Ulrich Hambach who, with support from Daniel, developed and ran the website for the second circular (including conference registration and abstract submission). Secondly, we thank the leaders and organisers of the field trips, which always involve considerable time and effort to prepare and enact: Ioan Seghedi (Romania), Alexandru Szakács (Romania), and Zoltán Pécskay (Hungary), who additionally provide the public lecture on Monday evening summarizing their career-long research on tackling the time evolution of Carpathian volcanism and geodynamic processes at play in the region (e.g., Seghedi et al., 2004), Ulrich Hambach (Germany), David Karátson (Hungary), and Daniel Veres (Romania). Staff of the venue, Resort ‘Cheile Gradistei’ Fundata, have been very supportive of the conference from the outset and we appreciate and thank them, and others involved, in providing us with accommodation, meals, refreshments, and entertainment, and for hosting us so well. The student and ECR helpers, Aritina 3

Haliuc, Akos Botezatu, Anca Avram, Viorica Tecsa, and Madalina Groza, who met many of the participants on arrival at Bucharest, and who are helping with technical support during the conference, are thanked, as are those chairing the sessions and judging the student presentations.

The conference has been supported financially primarily by the Stratigraphy and Chronology Commission (SACCOM) (in which INTAV is one of a number of focus groups) of INQUA, being awarded €4600 (grant 1710P) to support 19 ECRs and students. This support was provided to support the objectives of INTAV’s EXTRAS project: EXTending tephRAS as a global geoscientific research tool stratigraphically, spatially, analytically, and temporally. Additional financial support was provided by Babes-Bolyai University, Cluj-Napoca, Romania, through the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme ERC-2015- STG (grant agreement 678106; PI, A. Timar-Gabor) and the Department of Physical Geography, Eötvös Lorand University, Budapest, Hungary (PI, D. Karátson). We also acknowledge administrative and logistical support from the Romanian Academy (Cluj-Napoca Branch), Institute of Speleology, Romanian Academy, and BayCEER, University of Bayreuth, Germany (which hosted the second circular website). The University of Waikato, Hamilton, New Zealand, provided funds for the student awards for ‘best oral’ and ‘best poster’ papers, with cartographic support from Betty-Ann Kamp. Considerable in-kind support has been provided by institutions in Romania and Germany, and by the home institutions of the members of the LOC and INTAV executive (listed below), who have worked together to organise the conference.

LOC ! Daniel Veres ([email protected]; [email protected]), Romanian Academy, Institute of Speleology and Babes-Bolyai University, Romania (chair/convener) ! Ulrich Hambach ([email protected]), University of Bayreuth, Germany ! David Karátson ([email protected]), Eötvös Lorand University, Budapest, Hungary ! Alida Timar-Gabor ([email protected]), Babes-Bolyai University, Cluj, Romania ! Alexandru Szakács ([email protected]), Sapientia University, Cluj, Romania ! Ioan Seghedi ([email protected]), Institute of Geodynamics, Romanian Academy, Bucharest, Romania ! Cristian Panaiotu ([email protected]), University of Bucharest, Romania

INTAV executive committee ! Britta Jensen ([email protected]), University of Alberta, Canada ! Peter Abbott ([email protected]), University of Bern, Switzerland ! Takehiko Suzuki ([email protected]), Tokyo Metropolitan University, Japan ! Siwan Davies ([email protected] UK), Swansea University, Wales, UK (Siwan was co-opted into the committee in August, 2017, following Vicky Smith’s resignation) ! David Lowe ([email protected]), University of Waikato, New Zealand ! Victoria Smith (University of Oxford, UK) (Vicki was involved in early conference preparations before resigning from the INTAV committee in 2017).

Future of global tephrochronology and potential role of INTAV

A very important session during the conference on the last day will be to discuss the future activities of INTAV and how these may best be implemented to satisfy the needs of the global tephra community. The INTAV committee is aware that our time as a formal international focus group (IFG) within SACCOM is ending under the current rules because we have been operating as an IFG since 2007 via the INTREPID and EXTRAS projects (normally IFGs operate for a maximum of eight years in INQUA). Our collaborations within INQUA, and support from the INQUA executive and SACCOM presidents in this period, have been greatly appreciated, INTAV has been active and productive, and much goodwill is very much evident today within the tephra community with regard to working closely with INQUA. Nevertheless, the president of the INQUA Executive Committee, Allan Ashworth (USA), noted in the latest Quaternary Perspectives newsletter (March 2018) that although INQUA funds IFGs, projects, and skills activities during inter-congress years, “the current structure has become too structured, too complex, too misunderstood, and needs to be simplified to allow for more flexibility. Good agreement was reached [in a meeting this year] in Beijing to present the International Council (IC) in Dublin [in 2019] with a proposal for the future which will simplify 4 the process of making awards. This was also part of a larger discussion about the [five] commissions, which have now been in existence for 15 years. A review of the commissions will be undertaken in the coming year and will help shape discussion about their future with the IC.”

Therefore the INTAV meeting scheduled for the final session of the conference is potentially far-reaching and participants are asked to consider and be prepared to respond to a series of questions as follows:

(1) Do you see a future for INTAV, or a similar group mainly comprising tephra specialists globally? (2) What are its aims? (3) How do we best meet those aims (assuming the response to (1) is positive), including through: (a) renewed association with INQUA (https://www.inqua.org/) in some way; or (b) as a stand-alone organisation such as INTIMATE; or (c) as a stand-alone new international society or association; or (d) by 'intensification' of the INTAV role by possibly attempting to gain financial support from, for example, European Union COST funding, and to work on annual workshops/meetings towards specified research objectives that relate to the funding; or (e) to form a new group within an organisations other than INQUA such as the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) (http://www.iugg.org/associations/iavcei.php). IAVCEI is one of eight semi-autonomous associations under the umbrella of the International Union of Geology and Geodesy (IUGG) (http://www.iugg.org/), which is at comparable ‘rank’ to INQUA, and (like INQUA) is one of ~30 scientific unions presently grouped within the International Council for Science (ICSU). IAVCEI currently hosts 14 commissions including, for example, “Cities on Volcanoes”, “Statistics in Volcanology”, Tephra Hazard Modelling”, “Collapse Calderas”, “Volcanic Lakes”, and “Volcanic Hazards and Risk”.

Each of these commissions normally hosts a stand-alone meeting (such as the “Cities on Volcanoes” meeting in Napoli, Italy, in September 2018), or an equivalent activity such as a targeted workshop every four years, and is run by an elected committee − not much different from the way INTAV has been run since 2007. Including 1990, COT-INTAV has hosted six inter-INQUA conferences, and has been involved with a number of workshops as well, and so an average frequency of four-yearly meetings has been met, more or less. IAVCEI hosts a full congress meeting every four years (the next being held in Rotorua, New Zealand, in February, 2021). Membership of IAVCEI requires a fee payable annually or four-yearly by individuals. Based on preliminary discussions with some of the leaders of these commissions, potentially a new “Commission on Tephrochronology” would be feasible within IAVCEI. Such an association would not preclude members from taking part in INQUA congresses, nor preclude them proposing and convening tephra-based sessions as is being done by INTIMATE, for example, for the full INQUA Congress in Dublin. (4) Would you as a member of INTAV be available to undertake a leadership role in INTAV or successor organisation to help it meet its (newly defined) aim and objectives?

The aim of COT in 1961 was expressed simply by Kobayashi (1965): “To advance the progress of the method of tephrochronology and Quaternary research based on tephrochronology”. This aim is embedded in the more expansive aims of the EXTRAS project: to help improve and develop new methodologies of tephrochronology to support and facilitate many Quaternary research initiatives ranging from paleoenvironmental reconstruction to archaeology, as well as geochronological and volcanological applications (see http://www.comp.tmu.ac.jp/tephra/intavtmu/link.html).

We wish all participants a most enjoyable, interesting, and informative field conference here in Transylvania, and a safe journey home.

Members of the LOC and INTAV executive committee, 1 June 2018

5

References

Ashworth, A. 2018. INQUA president’s report. Quaternary Perspectives 25 (1), 1-2. Davies, S.M. 2015. Cryptotephras: the revolution in correlation and precision dating. Journal of Quaternary Science 30, 114-130. Dugmore, A.J. 1989. Icelandic volcanic ash in Scotland. Scottish Geographical Magazine 105, 168- 172. Froese, D.G., Alloway, B.V., Lowe, D.J. 2008. John A. Westgate – global tephrochronologist, stratigrapher, mentor. Quaternary International 178, 4-9. Karátson, D., Veres, D., Wulf, S., Gertisser, R., Magyari, E., Bormann, M. 2017. The youngest volcanic eruptions in east-central Europe – new finds from the Ciomadul lava dome complex, East Carpathians, Romania. Geology Today 33 (2), 62-67. Kearney, R., Albert, P.G., Staff, R.A. Pál, I., Veres, D., Magyari, E., Bronk Ramsey, C. 2018. Ultra- distal fine ash occurrences of the Icelandic Askja-S Plinian eruption deposits in southern Carpathian lakes: new age constraints on a continental scale tephrostratigraphic marker. Quaternary Science Reviews 188, 174-182. Kobayashi, K. 1965. Commission on tephrochronology. Report from the conference on tephrochronology held at the VIth International Congress of INQUA, vol. 1, 781-789. Lane, C.S., Lowe, D.J., Blockley, S.P.E., Suzuki, T., Smith, V.C. 2017. Advancing tephrochronology as a global dating tool: applications in volcanology, archaeology, and palaeoclimatic research. Quaternary Geochronology 40, 1-7. Lowe, D.J., Moriwaki, H., Davies, S.M., Suzuki, T., Pearce, N.J.G. (editors) 2011. “Enhancing tephrochronology and its application (INTREPID project): Hiroshi Machida commemorative volume.” Quaternary International 246, 1-395. Seghedi, I., Downes, H., Szakács, A., Mason, P.R.D., Thirlwall, M.F., Rosu, E., Pecskay, Z., Marton, E., Panaiotu, C., 2004. Neogene-Quaternary magmatism and geodynamics in the Carpathian- Pannonian region: a synthesis. Lithos 72, 117-146. Smith, D.G.W., Westgate, J.A. 1969. Electron probe technique for characterising pyroclastic deposits. Earth and Planetary Science Letters 5, 313-319. Westgate, J.A., Gold, C.M. (compilers) 1974. “World Bibliography and Index of Quaternary Tephrochronology”. University of Alberta, Edmonton, UNESCO and INQUA, 528 pp.

6

Programme Sunday, 24.06.2018: Ice Breaker and Registration

Time 17:30 Ice breaker and on-site registration Monday, 25.06.2018: Oral and Poster Sessions

Time 08:00 On-site registration 08:15 WELCOME ADDRESS

Oral session 1 08:30 Keynote 1: Sabine Wulf et al.: Unifying Europe: the enhanced use of (crypto)tephra layers for synchronising palaeoenvironmental records O 1.1: Peter Abbott et al.: Tracing Marine Cryptotephras in the North Atlantic during 09:00 the Last Glacial Period O 1.2: Anna Bourne et al.: The Greenland Ice-Core Tephra Record – potential for 09:15 correlation and insights into Icelandic volcanism. O 1.3: Simon Larsson et al.: An encouraging tephrostratigraphy in southernmost 09:30 Sweden: results from Körslättamossen 09:45 O 1.4: Sean Pyne-O'Donnell et al.: The Glacier Peak ash in Scotland O 1.5: Esther Ruth Gudmundsdóttir et al.: Tephrochronology as a tool in 10:00 volcanology: Early Holocene explosive volcanism in Iceland 10:15 O 1.6: Frank Sirocko et al.: The ELSA-Tephra-Stack-2018 10:30 Coffee Break

Oral session 2 11:00 O 2.1: Frank Lehmkuhl et al.: The Eltville Tephra (Western Europe): distribution and timing for an important Western European stratigraphic marker O 2.2: Polina Vakhrameeva et al.: The cryptotephra record of the Marine Isotope 11:15 Stage 12 to 9 interval (460–305 ka) at Tenaghi Philippon, Greece: Exploring chronological markers for the Middle Pleistocene of the Mediterranean region O 2.3: Stefan Wastegård et al.: New results from São Miguel, Azores Islands, 11:30 confirming the links between proximal tephras and distal sites in mainland Europe O 2.4: Ali Monteath et al.: Late glacial – early Holocene Cryptotephra from the 11:45 Falkland Islands (Malvinas) O 2.5: Chunqing Sun et al.: Ash from the early Holocene Changbaishan eruption: A 12:00 new marker horizon across East Asia O 2.6: Julie Christin Schindlbeck et al.: 100- kyr cyclicity in volcanic ash 12:15 emplacement: evidence from a 1.1 Myr tephra record from the Nothwest Pacific

Keynote 2: Vera Ponomareva et al.: Explosive eruptions and ash dispersal patterns in 12:30 the northwest Pacific

7

13:00 Lunch 14:00 Poster Session 1 15:30 Coffee Break and Poster Session

Oral session 3 16:00 Keynote 3: Michael Sigl et al.: Cryptotephra and sulphur in polar ice – a strong tandem for climate research O 3.1: Andrew Dugmore et al.: The value of disrupted, distorted, disturbed and re- 16:30 deposited tephra sequences: from classical tephrochronology to a tephra science of past environments. O 3.2: David J Lowe et al.: Earth-shaking insight from liquefied tephra layers in lakes 16:45 in central Waikato region, New Zealand: a new tool to evaluate and date palaeoseismicity? O 3.3: Yu-Tuan (Doreen) Huang et al.: DNA extraction from paleosols on tephras: 17:00 insights in the search for ancient DNA from past terrestrial ecosystems O 3.4: Remedy C. Loame et al.: Using CT scanning for reconnaissance and detection 17:15 of cryptotephras in ~22,000-yr-old lake sediments, central Waikato region, New Zealand O 3.5: Leonie Peti et al.: Fingerprinting rhyolitic tephra layers in New Zealand with µ- 17:30 XRF core scanning: Towards a faster and non-destructive method for tephrochronology O 3.6: Jack Longman et al.: Authigenic calcite formation in tephra: A mechanism for 17:45 enhanced carbon drawdown at the end of the PETM

Public lecture 19:00 Public Lecture: Ioan Seghedi et al.: Geological and volcanological outline of the Carpathian-Pannonian Region with emphasis on the Romanian territory 19:45 Dinner

Tuesday, 26.06.2018: Intraconference fieldtrip

Time Intraconference fieldtrip to the Persani volcanic field 08:00 (excursion leader: Ioan Seghedi) 20:00 Dinner

8

Wednesday, 27.06.2018: Oral and Poster Sessions

Time Oral session 4

08:30 O 4.1: Gonca Gencalioglu Kuscu et al.: Challenges in dating of Nisyros tephra O 4.2: Janina Bösken et al.: Chances and challenges in dating tephra marker horizons 08:45 by luminescence dating techniques O 4.3: Christoph Schmidt: Direct and indirect luminescence dating of tephra: 09:00 methodological considerations O 4.4: Jeffrey Oalmann et al.: LA-ICP-MS mapping of volcanic glass: A promising 09:15 technique for measuring trace element abundances in small tephra particles O 4.5: Egor Zelenin et al.: A Bayesian age-depth modelling of a full Pliocene- 09:30 Quaternary tephrochronological framework for the Northwest Pacific Deep Sea cores O 4.6: Lauren Davies et al.: Modern cryptotephra and high-resolution Bayesian age 09:45 modelling of peat bog profiles: a case study using six sites from Alberta, Canada Keynote 4: Maarten Blaauw: More dates and use Bayes - recommendations for robust 10:00 age-depth models 10:30 Coffee Break 11:00 Workshop chronological modelling (promoter: Maarten Blaauw) 13:00 Lunch 14:00 Poster Session 2 15:30 Coffee Break and Poster Session

Oral session 5 16:00 Keynote 5: Dávid Karátson et al.: Volcanic and geomorphic evolution of the Late Quaternary Ciomadul lava dome complex, the youngest eruptive center of the Carpathian Basin O 5.1: Enikő Magyari et al.: Paleoclimate and paleoenvironment in the Ciomadul 16:30 volcanic area after and before the last eruption O 5.2: Szabolcs Harangi et al.: Eruption ages and geochemical fingerprints of the 16:45 distal tephras from the Late Pleistocene Ciomadul volcano, East Carpathians O 5.3: Réka Lukács et al.: Correlation of Miocene tephras in the Carpathian- 17:00 Pannonian Region and the surrounding areas O 5.4: Rebecca Kearney et al.: Cryptotephra investigation in the Carpathian 17:15 Mountains, Romania O 5.5: Yu Fu et al.: Tephra layer refining Middle Pleistocene chronology of Serbian 17:30 loess O 5.6: Niklas Leicher et al.: Tephrostratigraphy and chronology of the Lake Ohrid 17:45 DEEP site record of the last 1.4 Ma

19:00 Conference Dinner

9

Thursday, 28.06.2018: Oral and Poster Sessions

Time Oral session 6

Keynote 6: Caroline Bouvet de Maisonneuve et al.: Improving our understanding of 08:30 Southeast Asian volcanic eruption histories, with an emphasis on Sumatra (Indonesia) O 6.1: Marcus Phua et al.: Tephrostratigraphy in Southeast Asia: towards unravelling 09:00 the eruptive history of Sumatran Volcanoes O 6.2: Takehiko Suzuki et al.: Identification of Lower Pleistocene widespread tephras 09:15 associated with huge caldera-forming eruptions in Northeast Japan (Tohoku) using LA– ICP–MS and SEM–EDS analyses O 6.3: Ajab Singh et al.: Petrography, geochemistry and 40Ar/39Ar dating of YTT 09:30 ash, Purna alluvial basin, Central India O 6.4: Britta Jensen et al.: A late Pleistocene to Holocene cryptotephra framework for 09:45 paleoenvironmental records from the Midwest to east coast of North America O 6.5: Catherine Martin-Jones et al.: Lake sediments provide the first eruptive 10:00 history for Corbetti, a high-risk Main Ethiopian Rift volcano O 6.6: Celine Vidal et al.: Timing and dispersal of Middle Pleistocene caldera-forming 10:15 eruptions in the Ethiopian Rift 10:30 Coffee Break

Oral session 7 11:00 Keynote 7: John Westgate: Bandelier Tuff (1.24 Ma) from the Valles caldera in New Mexico discovered in southwestern Canada: a career-long problem solved O 7.1: Jenni L Hopkins et al.: Multi-criteria correlation of tephra deposits to source 11:30 centres applied in the Auckland Volcanic Field, New Zealand O 7.2: Nicholas Pearce et al.: Can we correlate variably weathered, phenocrystic 11:45 intermediate tephras using both bulk and single grain analyses? An example from the Lepué Tephra, Southern Andean Volcanic Zone, Chile. O 7.3: Jonathan Moles et al.: Widespread dispersal of rhyolitic tephra from a 12:00 subglacial volcano: linking the terrestrial palaeoenvironment with climate records O 7.4: Katharine Cashman et al.: Sizing up volcanic ash: how do we measure ash 12:15 size, and why should we care? O 7.5: Hannah Buckland et al.: The isopach problem: the consequences of uncertainty 12:30 in the thickness of the distal Mazama tephra O 7.6: Alison Rust et al.: Origins, complications and utility of variations in ash 12:45 componentry 13:00 Lunch 14:00 Poster Session 3 15:30 Coffee Break and Poster Session Round table: INTAV outlook and future; inc. Database Discussion; Student 16:00 Awards

19:30 Dinner

10

Friday to Sunday, 29.06.2018 - 1.07.2018, Postconference fieldtrip

Postconference fieldtrip “Late Quaternary Carpathian volcanism and Lower Danube paleoclimate"

11

List of Posters

POSTER Session 1

Nick Cutler, Richard Streeter, Andrew Dugmore P 1.1 Vegetation cover, slope and the preservation of terrestrial tephra layers Nick Cutler, Richard Streeter, Lauren Shotter, Joseph Marple, Jean Yeoh, Andrew Dugmore P 1.2 Tephra transformations: variable preservation of tephra layers from two well-studied eruptions Gwydion Jones, Siwan Davies, Neil Loader, Sarah Davies, Mike Walker P 1.3 A Lateglacial to mid Holocene tephrochronological record from Llyn Llech Owain, south Wales Niklas Leicher, Biagio Giaccio, Bernd Wagner, Giorgio Manella, Giovanni Zanchetta, Elenora Regattieri, Sebastien Nomade, Alison Pereira, Thomas Wonik, Melanie Leng, Camille Thomas, Daniel Ariztegui, Mario Gaeta, P 1.4 Fabio Florindo, Elizabeth Niespolo, Paul Renne Tephrostratigraphy and tephrochronology of a 430 ka sediment record from the Fucino Basin, central Italy, unites Mediterranean and North Atlantic archives Richard Streeter, Andrew Dugmore, Nick Cutler

P 1.5 The potential of tephra for paleao reconstruction and assessing landscape resilience

Christel van den Bogaard, B.J.L. Jensen, N.J.G. Pearce, D.G. Froese, 00 : M.V. Portnyagin, V.V. Ponomareva, V. Wennrich P 1.6 16 - Distal – ultradistal: Visible tephra layers in Lake El’gygytgyn, Siberia, Far East Russian Arctic

14:00 Philip Kyle, M.J. Lee P 1.7 New occurrences of the widespread 1254 C.E. tephra in Antarctic ice and

Monday June 25, 2018 25, June Monday identification of Rittmann volcano, Antarctica as the eruptive source. Bergrún Arna Óladóttir, Olgeir Sigmarsson, Guðrún Larsen P 1.8 Tephra improves understanding of explosive eruption frequency and magmatic evolution at active volcanoes Bergrún Arna Óladóttir, Evgenia Illyinskaya, Guðrún Larsen, Magnús Guðmundsson, Kristín Vogfjord, Emmanuel Pagneux, Björn Oddsson, Sara P 1.9 Barsotti, Sigrún Karlsdóttir Catalogue of Icelandic Volcanoes - An open access web resource Daníel Freyr Jónsson, Esther Ruth Gudmundsdóttir, Bergrún Arna Óladóttir, Gudrún Larsen, Olgeir Sigmarsson P 1.10 Mid Holocene eruptions in Hekla volcano: the Hekla Ö, Hekla MÓ and Hekla DH tephra layers Masayuki Torii, Toshiaki Hasenaka, Shinji Toda, Ken-ichi Nishiyama, Mitsuru Okuno P 1.11 Event history of active faults and slope failures based on tephra stratigraphy - An example of the 2016 Kumamoto earthquake Lauren Davies, Duane Froese P 1.12 A Holocene cryptotephra record from north-western Canada with more than 35 distal tephra falls since 10,500 cal yr BP

12

Britta Jensen, Foo Zhen Hui P 1.13 Glass geochemical variability of historic Mount St. Helens eruptions and insights into eruption characteristics Andrew Dugmore, Anthony Newton, Emily Lethbridge P 1.14 Wizards’ Floods and classical tephrochronology Anna Bourne, Peter Langdon, David Sear P 1.15 The potential of tephrochronology for linking climate, environmental change and human colonisation of the South Pacific Mitsuru Okuno, Agung Harijoko, I Wayan Warmada, Toshio Nakamura, Tetsuo Kobayashi P 1.16 Radiocarbon chronology of the post-caldera volcanoes of Buyan-Bratan caldera in the island of Bali, Indonesia Yunus Baykal, Ulrich Hambach, Igor Obreht, Christian Zeeden, Daniel Veres, Zoran Peric, Philipp Schulte, Frank Lehmkuhl, Slobodan B. P 1.17 Markovic The Campanian Ignimbrite tephra layer: How far north does it reach?

POSTER Session 2

Yasuo Miyabuchi P 2.1 Post-caldera tephrostratigraphic framework of Aso Volcano, southwestern Japan Daniela Constantin, Daniel Veres, Cristian Panaiotu, Valentina Anechitei- Deacu, Stefana Madalina Groza, Robert Csaba Begy, Szabolcs Kelemen, Jan-Pieter Buylaert, Ulrich Hambach, Slobodan Marković, Natalia P 2.2 Gerasimenko, Alida Timar-Gabor Luminescence age constraints on the Pleistocene-Holocene transition

recorded in loess sequences across SE Europe Aritina Haliuc, Ina Neugebauer, Christine Lane, Stefan Engels, Gwydion Jones, Dirk Sachse, Achim Brauer P 2.3

Independent chronostratigraphic markers and varve chronology in the Lateglacial palaeoenvironmental record of Lake Hämelsee, N-Germany 16:00

- Alejandro Cisneros de León, Julie Christin Schindlbeck, Axel K. Schmitt, Steffen Kutterolf P 2.4

14:00 Zircon in tephra as a novel tool to decrypt geologic and archaeological archives: a case study from Central America Maria Gehrels, Rewi Newnham, David Lowe, Paul Augustinus

Wednesday, June 27, 2018 27, June Wednesday, P 2.5 A new record of late Holocene (crypto)tephras clarifies timing of early Polynesian impact in northern New Zealand Remedy C. Loame, David J. Lowe, Richard E. Johnston, Elizabeth Evans, Adrian Pittari, Vicki G. Moon, Willem P. de Lange, Siwan M. Davies, P 2.6 Christina R. Magill, Marcus J. Vandergoes, Andrew B.H. Rees, Nic Ross CT and micro-CT scanning of liquefied tephra deposits in ~22,000-yr-old lake sediments, central Waikato region, New Zealand, and implications David J Lowe, Nick JG Pearce, Murray A Jorgensen, Steve C Kuehn, Christian A Tryon, Chris L Hayward P 2.7 Are numerical and statistical methods the panacea for correlating tephras or cryptotephras using compositional data? 13

David J Lowe, Andrew BH Rees, Rewi M Newnham, Zoë J Hazell, Maria J Gehrels, Dan J Charman, Matt J Amesbury P 2.8 Isochron-informed Bayesian age modelling for tephras and cryototephras: application to mid-Holocene Tūhua tephra, northern New Zealand Stephen Kuehn, Janine Krippner, Cheryl Cameron, Simon Goring, Kerstin Lehnert, Douglas Fils, Amy Myrbo, Anders Noren P 2.9 Tephra data without borders: Building a global and interdisciplinary tephra data system Stephen Kuehn Improved EPMA of tephra glasses using TDI, combined EDS+WDS, MAN, P 2.10 a multi-standard blank correction, and a multi-standard normalization to facilitate smaller beams, more elements, greater precision, and better between-session reproducibility Jenni L Hopkins, Richard Wysoczanski, Alan Orpin P 2.11 Deposition, re-working and recycling of Holocene rhyolitic tephra in marine sediments at an active plate margin Takehiko Suzuki, Makoto Kobayashi, Fumikatsu Nishizawa, Kaori Aoki, Daisuke Ishimura, Daichi Nakayama P 2.12 Recent progress and perspective in tephrochronological studies for eruption histories of Quaternary volcanoes in north Izu Islands, off Tokyo Metropolitan Area, Japan Catherine Martin-Jones, Christine Lane, Christian Wolff, Maarten Van Daele, Thijs Van der Meeren, Darren Mark, Phil Barker, Maarten Blaauw, P 2.13 Melanie Leng, Barbara Maher, Dirk Verschuren A ~260-ka eruptive history for Kilimanjaro derived from Lake Challa sediments Peter Abbott, Samuel Jaccard, Steve Barker, Julia Gottschalk, Luke Skinner, Claire Waelbroeck P 2.14 Towards improved constraints on the timing of deep-water ventilation changes and the marine reservoir effect in the Southern Ocean between 40- 10 kyr BP: A tephrochronological and radiocarbon approach Nicholas Pearce, Guilherme Gualda, John Westgate, Emma Gatti P 2.15 Five magma bodies fed the ~75 ka Youngest Toba eruption: tephra glass evidence for YTT magma storage and discharge Ashok K. Srivastava, Ajab Singh P 2.16 YTT ash from Purna alluvial basin, Central India: its comparison with Toba ashes from continental deposits of India Aleksandra Zawalna-Geer, Jan Lindsay, Siwan Davies, Paul Augustinus, Sarah Davies P 2.17 New insight into frequency of ash fall impacting the Auckland region, New Zealand

14

POSTER Session 3

Rhys Timms, Jenni Sherriff, Katie Preece, Simon Blockley, Keith Wilkinson, Darren Mark, Daniel Adler P 3.1 Preliminary results from the PAGES* project (*Pleistocene Archaeology, Geochronology and Environment of the Southern Caucasus) Milica Radakovic, Rastko Markovic, Daniel Veres, Urlich Hambach, Milivoj Gavrilov, Igor Obreht, Christian Zeeden, Frank Lehmkuhl, Hao P 3.2 Qingzhen, Slobodan Markovic DBTG-Danube Basin Tephra Geodatabase Daniel Veres, Ulrich Hambach, Alida Timar-Gabor, Sabine Wulf, Christian Zeeden, Igor Obreht, Janina Bösken, Milica G. Radaković, Slobodan B. P 3.3 Marković, Frank Lehmkuhl Tephra marker horizons in loess records from southeastern Europe Daniel Veres, Valentina Anechitei-Deacu, Dávid Karátson, Sabine Wulf, Alida Timar-Gabor, Ulrich Hambach, Frank Lehmkuhl, Stephan Pötter, P 3.4 Janina Bösken, Enikő Magyari, Igor Obreht, Slobodan B. Marković Geochemical, sedimentological, and chronological considerations of several

Late Quaternary key marker tephra of Carpathian origin Anthony Newton, Richard Streeter, Colleen Strawhacker, Adam Brin, Rachel Opitz, Andrew Dugmore, Tom McGovern

P 3.5 Integrating tephrochronology with archaeology, the humanities, and palaeoenvironmental and palaeoclimatic records (dataARC) 16:00 - Christian Laag, Ulrich Hambach, Akos Botezatu, Yunus Baykal, Daniel Veres, Thomas Schönwetter, Jannis Viola, Christian Zeeden, Milica G. 14:00 Radaković, Igor Obreht, Mladjen Jovanović, Janina Bösken, Frank P 3.6 Lehmkuhl, Slobodan B. Marković The geographical extent of the “L2-Tephra”: a widespread marker horizon Thursday, June 28, 2018 28, June Thursday, for the penultimate glacial (MIS 6) on the Balkan Peninsula Stephan Pötter, Janina Bösken, Ulrich Hambach, Daniel Veres, Dávid Karátson, Sabine Wulf, Igor Obreht, Slobodan Marković, Frank Lehmkuhl P 3.7 Multi-proxy-approach in palaeoenvironmental reconstructions using terrestrial sequences from southeastern Transylvania, Romania Jayde Hirniak, Eugene Smith, Racheal Johnsen, Shelby Fitch, Caley Orr, David Strait, Minghua Ren, Christopher E. Miller, Fabio Negrino, Julien Riel-Salvatore, Marco Peresani, Stefano Benazzi, Claudine Gravel-Miguel, P 3.8 Curtis Marean, Jamie Hodgkins Using cryptotephra to link Neanderthal and AMH Middle Paleolithic sites in NW Italy Donatella Insinga, Paola Petrosino, Gert J. de Lange, Fabrizio Lirer, Roberto Sulpizio, Jiawang Wu P 3.9 The 4 ka-2 ka cryptotephra record in the Central Mediterranean: new potential isochrones for high-resolution stratigraphy Amy McGuire, Christine Lane, Katy Roucoux, Ian Lawson, Paul Albert P 3.10 A tephrostratigraphy for Lake Ioannina, North West Greece Ralf Gertisser, Rebecca Wiltshire P 3.11 Tephra deposits within the Skaros lava sequence, Santorini, Greece

15

Jennifer Saxby, Katharine Cashman, Frances Beckett, Alison Rust P 3.12 Using morphological analysis to explain the presence of large grains in distal cryptotephra deposits Paola Petrosino, Donatella Domenica Insinga, Flavia Molisso, Marco Sacchi P 3.13 Tephra markers as a tool for the timing of the morphotectonic dynamics in the Campi Flegrei caldera Valerie Menke, Steffen Kutterolf, Carina Sievers, Julie Christin Schindlbeck, Gerhard Schmiedl P 3.14 Cryptotephra in the Gulf of Taranto (Italy) as time marker for paleoclimatic studies: A combined qualitative and quantitative glass shard analyses Steffen Kutterolf, Julie Christin Schindlbeck P 3.15 Combined marine, lacustrine, and terrestrial tephrachronostratigraphy of Central America and its implications for volcanology and geology Viorica Tecsa, Daniel Veres, Natalia Gerasimenko, Christian Zeeden, Ulrich Hambach, Alida Timar-Gabor P 3.16 Multi-method luminescence dating of soil formation events in Last Glacial East European loess Anca Avram, Constantin Daniela, Veres Daniel, Kelemen Szabolcs, Obreht Igor, Hambach Ulrich, Marković Slobodan, Timar-Gabor Alida P 3.17 Multi-methods luminescence dating of the Batajnica loess section in south of the Carpathian Basin Ștefana Mădălina Groza, Daniela Constantin, Cristian George Panaiotu, Ramona Bălc, Timar-Gabor Alida P 3.18 Revisiting the chronology of Mircea Vodă loess-paleosol sequence, Romania

16

Evening Lecture

Public lecture: 2018-06-25, 19:00

Geological and volcanological outline of the Carpathian-Pannonian Region with emphasis on the Romanian territory 1 1 2 IOAN SEGHEDI , ALEXANDRU SZAKÁCS , ZOLTÁN PÉCSKAY 1 Institute of Geodynamics, Romanian Academy, 19–21 Jean-Luis Calderon str., Bucharest 020032, Romania 2 Institute of Nuclear Research of Hungarian Academy of Sciences, Bem tér 18/c, 4026 Debrecen, Hungary Contact: [email protected]

This is an outline of the magmatic processes in the Carpathian–Pannonian Region (CPR) from Early Miocene to Recent times with emphasis on the Romanian territory, based on the recent published data. The general geodynamic system was controlled by the collision of Africa with Eurasia, mainly by Adria that generated the Alps to the north, the Dinaride– Hellenide belt to the east that caused extrusion, collision and inversion tectonics in the CPR. These tectonic processes involved two microplates: ALCAPA and Tisza–Dacia. Competition between the different tectonic processes at both local and regional scales caused variations in the associated magmatism, mainly as a result of extension and differences in the rheological properties and composition of the lithosphere. Two basin systems developed: the Pannonian and Transylvanian basins. Weak lithospheric blocks (i.e., ALCAPA and western Tisza) generated the Pannonian basin and the adjacent Styrian, Transdanubian and Zărand basins which show high rates of vertical movement accompanied by a range of magmatic compositions. Strong lithospheric blocks (i.e. Dacia) were only marginally deformed, where strike–slip faulting was associated with magmatism and extension and generation of Transylvanian basin.

The CPR, as well the Romanian territory, contains magmatic rocks of highly diverse compositions: initially subalkaline felsic (rhyolite and dacite) then andesitic (calc-alkaline, adakite-like, transitional), K-alkalic, ultrapotassic and Na-alkalic, generated mainly in response to post-collisional tectonic processes.

Early Miocene felsic volcanism is dominated by calderas, the andesitic subalkaline, K- alkaline and ultrapotassic by composite volcanoes, monogenetic volcanic cones, dome/flow complexes and subvolcanic intrusive complexes and Na-alkalic by monogenetic volcanic fields of maars, diatremes, tuff cones, cinder/spatter cones and lava flows.

Major, trace element and isotopic data of post-Early Miocene magmatic rocks from the CPR suggest lithospheric mantle, as the main source, which preserved metasomatic components after the Cretaceous–Miocene subduction processes that were reactivated especially by extensional tectonic processes that allowed uprise of the asthenosphere.

17

Keynotes Keynote 1

Keynote 1 in Oral session 1: 25.06.2018, 08:30-09:00

Unifying Europe: the enhanced use of (crypto)tephra layers for synchronising palaeoenvironmental records 1 2 3 3 SABINE WULF , ACHIM BRAUER , JAMES COLLINS , MARC-ANDRÉ CORMIER , MARKUS J. 2 3 SCHWAB , DIRK SACHSE 1 Department of Geography, University of Portsmouth, United Kingdom 2 Helmholtz Centre Potsdam, German Research Centre for Geosciences GFZ, Section 5.2 Climate Dynamics and Landscape Evolution, Telegrafenberg, D-14473 Potsdam, Germany 3 Helmholtz Centre Potsdam, German Research Centre for Geosciences GFZ, Section 5.1 Geomorphology, Telegrafenberg, D-14473 Potsdam, Germany Contact: [email protected]

Tephra layers in sedimentary archives can provide valuable isochrons for independently dating sequences of palaeoenvironmental change. In combination with high-resolution chronologies (e.g. annual layer counting) and detailed multi-proxy data sets tephra layers further enable the alignment of different archives in order to test the pacing of regional climate change and respective environment responses.

Past studies in Europe were commonly restricted to visible tephra layers and hence limited the proxy data comparison to relatively small geographical areas. The recent advances of tephra methodological and micro-analytical techniques, however, allow for detection and chemical fingerprinting of tephra levels with low glass shard concentrations (cryptotephra). Consequently, cryptotephra studies have massively increased the number of tephra findings and extended the area of palaeoenvironmental sites that can use common tephras for detailed data comparison.

A first case study derives from a 900 km long W-E transect archive alignment of terrestrial Lateglacial sequences across central Europe (Lake Meerfelder Maar, Hämelsee, Rehwiese and Trzechowskie palaeolakes). Here, high-resolution (decadal) lake depositional, hydrological (biomarker δD) and vegetation data from annual laminated lake sediments were aligned by the Eifel Laacher See Tephra (LST, 12.9 ka) to test the spatiotemporal relationships of environmental responses at the onset of the Younger Dryas cooling (e.g., Wulf et al., 2013; Słowiński et al., 2017; Jones et al., 2018; Collins et al., 2018). Furthermore, the finding of the Icelandic 12.1 ka Vedde Ash (VA) in Lake Meerfelder Maar (Lane et al., 2013) allowed for a first direct alignment of hydrological data from central Europe with the Greenland oxygen isotope record (Rach et al., 2014; Collins et al., 2018).

The results of these data comparisons reveal complex patterns of lead- and lag phase relationships of hydrological and vegetation changes in response to Greenland cooling (Rach et al., 2014; Collins et al., 2018) related to a reorganization of atmospheric circulation patterns over Europe at the onset of the Younger Dryas cold period. The ERC-funded project STEEPclim (‘Spatiotemporal evolution of the hydrological cycle throughout the European continent during past abrupt climate changes’) aims to reconstruct hydrological and vegetation changes via detailed biomarker analyses on further 10+ Lateglacial lacustrine sequences from across the entire European continent. Hence as part of this project, detailed cryptotephra studies of varved sequences from southern Germany (Steißlinger See) and Italy (Lago Grande di Monticchio) have been initiated. One major goal is to identify the Laacher See Tephra, the Vedde Ash, and other Lateglacial tephras of Italian provenance in these sequences to enable proxy data alignment into the Mediterranean region. The search for ultra-distal cryptotephras (LST, VA) in the tephra-dominated sediments of Lago Grande di 18

Monticchio, however, encounters new methodological challenges and limitations, some of which are presented here.

The results of proxy data alignment of Central European Lateglacial sequences demonstrate the immense value of tephras when applied as isochrones delivering an unprecedented picture of the anatomy of abrupt climatic change. The recent successful identification of Icelandic cryptotephra in Romanian lakes (Kearney et al., 2018) in combination with an improving Eastern Mediterranean (crypto)tephrostratigraphy suggest that there is also great potential to extend proxy-data comparison not only spatially into the Eurasian region but also to examine lead-lag-phase relationships during older climatic transitions.

References Collins, J., Aichner, B., Schenk, F., Engels, S., Lane, C., Maas, D., Neugebauer, I., Ott, F., Słowiński, M., Wulf, S., Brauer, A., Sachse, D. (2018). Influence of the Scandinavian Ice Sheet on spatiotemporal patterns of European hydroclimate during the Younger Dryas from decadally-resolved lacustrine biomarker records. EGU abstracts, EGU2018-15618, Vienna, Austria, 8-13 April 2018. Jones, G., Lane, C.S., Brauer, A., Davies, S.M., de Bruijn, R., Engels, S., Haliuc, A., Hoek, W.Z., Merkt, J., Sachse, D., Turner, F., Wagner-Cremer, F. (2018). The Lateglacial to early Holocene tephrochronological record from Lake Hämelsee, Germany: a key site within the European tephra framework. Boreas 47, 28-40. Kearney, R., Albert, P.G., Staff, R.A., Pál, I., Veres, D., Magyari, E., Bronk Ramsey, C. (2018). Ultra- distal fine ash occurrences of the Icelandic Askja-S Plinian eruption deposits in Southern Carpathian lakes: New age constraints on a continental scale tephrostratigraphic marker. Quaternary Science Reviews 188, 174-182. Lane, C.S., Brauer, A., Blockley, S.P.E., Dulski, P. (2013). Volcanic ash reveals time-transgressive abrupt climate change during the Younger Dryas. Geology 41, 1251-1254. Rach, O., Brauer, A., Wilkes, H., Sachse, D. (2014). Delayed hydrological response to Greenland cooling at the onset of the Younger Dryas in western Europe. Nature Geoscience 7, 109-112. Słowiński, M., Zawiska, I., Ott, F., Noryśkiewicz, A.M., Plessen, B., Apolinarska, K., Rzodkiewicz, M., Michczyńska, D.J., Wulf, S., Skubała, P., Kordowski, J., Błaszkiewicz, M., Brauer, A. (2017). Differential proxy responses to late Allerød and early Younger Dryas climatic change recorded in varved sediments of the Trzechowskie palaeolakes in Northern Poland. Quaternary Science Reviews 158, 94-106. Wulf, S., Ott, F., Słowiński, M., Noryśkiewicz, A.M., Dräger, N., Martin-Puertas, C., Czymzik, M., Neugebauer, I., Dulski, P., Bourne, A.J., Błaszkiewicz, M., Brauer, A. (2013). Tracing the Laacher See Tephra in the varved sediment record of the Trzechowskie palaeolakes in central Northern Poland. Quaternary Science Reviews 76, 129-139.

19

Keynote 2

Keynote 2 in Oral session 2: 25.06.2018, 12:30-13:00

Explosive eruptions and ash dispersal patterns in the northwest Pacific 1 2 3 1 VERA PONOMAREVA , MAXIM PORTNYAGIN , ALEXANDER DERKACHEV , LILIA BAZANOVA , 4 5 1 6 NATALIA BUBENSHCHIKOVA , EGOR ZELENIN , ALEXEY ROGOZIN , ANASTASIA PLECHOVA 1 Institute of Volcanology and Seismology, Russia 2 GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany and V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry, Russia 3 V.I. Il'ichev Pacific Oceanological Institute, Russia 4 P.P. Shirshov Institute of Oceanology, Russia 5 Geological Institute, Russia 6 V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry, Russia Contact: [email protected]

Large explosive eruptions are among the extreme natural events and can produce hemispheric or even global catastrophic effects. One of the prerequisites of predicting future volcanic catastrophes is the understanding of sizes and recurrence times of past similar events. At the same time, the global record of large eruptions remains incomplete even for the last millennia and deteriorates deeper in time as many eruptions are yet to be identified. This is particularly true for remote North Pacific volcanic arcs potentially hazardous for the Northern Hemisphere. Both Alaska-Aleutian and Kurile-Kamchatka arcs are highly explosive, which is testified by many nested calderas and numerous tephra layers buried in sediments of the surrounding seas. Ash clouds from North Pacific eruptions repeatedly affected the whole Northern Hemisphere, dispersing ash as far as Greenland, Svalbard, and northern Europe (Jensen et al., 2013; Bourne et al., 2016; van der Bilt et al., 2017; Cook et al., 2018). At the same time, our knowledge about the number, age, and extent of tephras from these arcs is still fragmentary.

Since 2009, we have been systematically studying tephra from the Kurile-Kamchatka and, occasionally, Alaska-Aleutian arcs using electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Our main aim is to compile a record of large explosive eruptions from the Kurile-Kamchatka volcanic arc for the late Miocene- Pleistocene times. Our studies are based on (1) proximal pyroclastic deposits in Kamchatka and Kurile Islands; (2) tephra findings in the northeast Asian mainland; and (3) tephra and cryptotephra from marine sediments in the northwest Pacific and western Arctic oceans. In this presentation, we will discuss our published (Ponomareva et al., 2015; 2017, 2018; Derkachev et al., 2016) and new results.

In Kamchatka and Kurile Islands, Holocene tephra layers are ubiquitous, well preserved and form continuous sequences. They are routinely used for reconstructions of the volcanic histories as well as for paleoclimatic, paleoseismological and archaeological studies (e.g., Braitseva et al., 1997; Ponomareva et al., 2017; Pendea et al., 2016). Extensive database of glass compositions for the Holocene Kurile-Kamchatka tephras permits their successful identification in ultra-distal localities, e.g., in Greenland.

Pre-Holocene tephra sequences in the Kurile-Kamchatka arc are rare as they were mostly removed by glacial processes. As non-erosive marine environments provide better tephra archives than the terrestrial ones, in our attempt to obtain a late Miocene-Pleistocene tephra record we turned to the marine tephra sequences. North Pacific marine sediments contain numerous tephra layers. The sources of most of these tephras are however, not known. Most of proximal deposits are welded and preserve no volcanic glass, which hampers their comparison to distal tephra and thus assessment of tephra sources and dispersal areas. In order to geochemically characterize altered tuffs and correlate those to distal tephra, we use immobile trace elements concentrations and compositions of melt inclusions in minerals. 20

Our current research, funded by the Russian Science Foundation, is aimed at the reconstruction of the continuous record of tephra layers for the last 6 Myr based on the three sedimentary cores taken at the Detroit Seamount ~700 km downwind from Kamchatka. Geochemical correlations of tephra layers among the cores have permitted the construction of the summary tephra sequence that includes 109 individual layers. The age model for the sequence is based on the integration of the available age-depth models for the individual cores and additional isotopic dates for tephras and their proximal counterparts. The resulting database will serve as a reference for correlations of Kurile-Kamchatka tephras to their ultra- distal counterparts and provide a record of major explosive eruptions in the NW Pacific.

Our research on cryptotephra from the marine sediments in the Bering and Okhotsk seas and in the Arctic Ocean, over the distances of 600-1300 km from the volcanoes has demonstrated high background glass concentrations. This pattern attests to a significant input of volcanic material into marine sediments by currents or seasonal ice. Large amount of redeposited glasses may obscure the signal of primary, especially minor tephra falls, thus complicating tephrochronological studies in the area. At the same time, we were able to identify a number of cryptotephras including the 3.6 ka Aniakchak II tephra. The high concentration of the Aniakchak II glasses suggests that this tephra can be found still farther afield and serve as a major marker for the late Holocene sediments in the western Arctic Ocean.

References Bourne AJ, Abbott PM, Albert PG et al. (2016) Underestimated risks of recurrent long-range ash dispersal from northern Pacific Arc volcanoes, Sci. Rep. 6 Braitseva OA, Ponomareva VV, Sulerzhitsky LD et al. (1997) Holocene key-marker tephra layers in Kamchatka Russia. Quat Res 47: 125-139 Cook E, Portnyagin M, Ponomareva V et al. (2018) First identification of cryptotephra from the Kamchatka Peninsula in a Greenland ice core: Implications of a widespread marker deposit that links Greenland to the Pacific northwest. Quat Sci Rev 181:200-206 Derkachev AN, Nikolaeva NA, Gorbarenko SA et al. (2016) Tephra layers of in the Quaternary deposits of the Sea of Okhotsk: Distribution, composition, age and volcanic sources. Quat Int 425: 248-272 Jensen BJ, Pyne-O'Donnell S, Plunkett G et al. (2014) Transatlantic distribution of the Alaskan White River Ash. Geology 42: 875-878 Pendea IF, Harmsen H, Keeler D et al. (2016) Prehistoric human responses to volcanic tephra fall events in the Ust-Kamchatsk region, Kamchatka Peninsula during the middle to late Holocene. Quat Int 394: 51-68 Ponomareva V, Portnyagin M, Pendea IF et al. (2017) A full holocene tephrochronology for the Kamchatsky Peninsula region: Applications from Kamchatka to North America. Quat Sci Rev 168: 101-122 Ponomareva V, Polyak L, Portnyagin M et al. (2018) Holocene tephra from the Chukchi-Alaskan margin, Arctic Ocean: Implications for sediment chronostratigraphy and volcanic history. Quat Geochronol 45: 85-97 van der Bilt WG, Lane CS, Bakke J (2017) Ultra-distal Kamchatkan ash on Arctic Svalbard: Towards hemispheric cryptotephra correlation, Quat Sci Rev 164: 230-235

21

Keynote 3

Keynote 3 in Oral session 3: 25.06.2018, 16:00-16:30

Cryptotephra and sulphur in polar ice – a strong tandem for climate research 1 2 3 4 5 MICHAEL SIGL , GILL PLUNKETT , JOSEPH R. MCCONNELL , NELS IVERSON , MATTHEW TOOHEY 1 Department of Geosciences, Universtiy of Oslo, Oslo, Norway 2 School of Geography, Archaeology and Palaeoecology, Queen’s University Belfast, Belfast, UK 3 Desert Research Institute, Reno, USA 4 New Mexico Tech, Socorro, USA 5 GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany Contact: [email protected]

Volcanic eruptions have been identified as a primary driver of climate variability, impacting surface air temperature, atmospheric circulation and hydroclimate. The observational record of the timing of volcanic eruptions, their location, magnitude of sulphate aerosol injection and its atmospheric life-cycle, however, is often incomplete, with gaps in our record of past volcanic activity increasing dramatically before the Modern (pre-1800) era. This shortage in observational data strongly limits our understanding of the sensitivity of the Earth system to volcanism and the vulnerability of social and economic systems to the climate impact of past and future eruptions. Improving such understanding by using abrupt volcanically-triggered climatic shocks as test-cases of societal impact and response is one of the key aims of the “VICS - Volcanic Impacts on Climate and Society” Working Group, an open community effort implemented through PAGES (Past Global Changes).

A 2,500 year-long ice-core record of volcanic activity (Sigl et al., 2015) and resulting stratospheric sulphur injections (Toohey & Sigl, 2017) sheds new light on past volcanism and its relation to climate. Sulphuric acid layers in ice cores prove that several centuries were volcanically much more active than the recent one (Figure), calling into question the decision of modeling groups in support of the 5th Fifth Assessment Report of the IPCC to omit plausible eruptions in future climate simulations. Crypto-tephra now increasingly detected in polar ice cores allows to pinpoint source locations of past eruptions, providing precise dates of past eruptions and delineation of terrestrial, marine and polar environmental records onto a common chronology (e.g. Jensen et al.; 2014; Dunbar et al., 2017).

The Holocene (i.e. the past 11,700 years) saw a number of eruptions with sulfur injections outside the range modern human societies experienced - and will be in the focus during the 2nd phase of the VICS Working Group (2019-2021), provided that funding continues. I demonstrate how we can extract comprehensive data on the timing, magnitudes and source locations of past volcanic eruptions, using a bi-polar array of ice-core records from Greenland and Antarctica and employing novel, precisely dated, high-time resolution, tephra and aerosol measurements from ice cores.

References Sigl, M. et al.: Timing and climate forcing of volcanic eruptions for the past 2,500 years, Nature, 523, 543–549, 2015. Toohey, M. & Sigl, M.: Volcanic stratospheric sulfur injections and aerosol optical depth from 500 BCE to 1900 CE, Earth Syst Sci Data, 9, 809–831, 2017. Dunbar, N. W., Iverson, N. A., Van Eaton, A. R., Sigl, M., Alloway, B. V., Kurbatov, A. V., Mastin, L. G., McConnell, J. R., and Wilson, C. J. N.: New Zealand supereruption provides time marker for the Last Glacial Maximum in Antarctica, Sci Rep-Uk, 7, 2017.

22

Jensen, J.L., S. Pyne-O’Donnell, G. Plunkett, D.G. Froese, P.D.M. Hughes, M. Sigl, J.R. McConnell, M.J. Amesbury, P.G. Blackwell, C. van den Bogaard, C.E. Buck, D.J. Charman, J.J. Clague, V.A. Hall, J. Koch, H. Mackay, G. Mallon, L. McColl, and J.R. Pilcher: Transatlantic distribution of the Alaskan White River Ash. Geology, 42(10), 875-878, 2014.

Sulphur concentrations from an ice-core array in Antarctica during the Common Era.

Keynote 4

Keynote 4 in Oral session 4: 27.06.2018, 10:00-10:30

More dates and use Bayes - recommendations for robust age-depth models 1 MAARTEN BLAAUW 1 School of Natural and Built Environment, Queen's University Belfast, United Kingdom Contact: [email protected]

Over the past decades, a range of age-modelling techniques has been produced and taken up by the wider palaeo community. Some of these models appear quite easy to produce and understand, e.g., linear interpolation between the dated core depths, and at times they also present pleasantly narrow age estimates. However, through applying a range of age-models to existing data as well as simulations, it becomes apparent that these types of models are not very robust or reliable. They quickly break down in the presence of outliers and their error estimates are often highly over-optimistic. On the other hand, Bayesian age-models produce more realistic uncertainty estimates, are much more robust against outliers, work well at low, medium and high dating densities, and will produce more precise models as more dates are added.

Recent examples of tephra-based Bayesian age-models will be discussed, to showcase their potential for the tephrochronology community.

23

Keynote 5

Keynote 5 in Oral session 5: 27.06.2018, 16:00-16:30

Volcanic and geomorphic evolution of the Late Quaternary Ciomadul lava dome complex, the youngest eruptive center of the Carpathian Basin 1 2 3 4 1 DÁVID KARÁTSON , DANIEL VERES , PIERRE LAHITTE , SABINE WULF , TAMÁS TELBISZ , 5 6 1 3 ALEXANDRU SZAKÁCS , RALF GERTISSER , ÁGNES NOVOTHNY , STÉPHANE DIBACTO 1 Department of Physical Geography, Eötvös University, Budapest, Hungary 2 Institute of Speleology, Romanian Academy, Cluj-Napoca, Romania 3 GEOPS, Université Paris-Sud, Orsay, France 4 Department of Geography, University of Portsmouth, UK 5 Institute of Geodynamics, Romanian Academy, București, Romania 6 School of Geography, Geology and the Environment, Keele University, Keele, UK Contact: [email protected]

Ciomadul, the youngest eruptive center of the Carpatho-Pannonian Region (CPR), is located in the East Carpathians at the southernmost end of the Intra-Carpathian Volcanic Range. It is a peculiar, well-preserved lava dome complex hosting two crater lakes (Lake St. Ana and Mohos peat bog). Here, summarizing recent results of a multidiscplinary research (Karátson et al. 2016, 2017 and submitted, Veres et al. 2017, Wulf et al. 2016, Lahitte et al. submitted), we present physical volcanological, tephrostratigraphical, paleo-environmental, various geochronological and morphometrical methods to infer the complex volcanic and paleo- geomorphic history of the volcano.

Ciomadul, beginning its history in a fluvio-lacustrine environment (Fielitz and Seghedi 2005), had first a long-term (ca. 800 to 400 ka), volumetrically insignificant dome-building stage. This oldest activity was constrained to the southern and eastern part. Subseqently, most of the volcanic field (ca. 80% in area) developed during the past ca. 200 ka. The evolution of this second stage was twofold. From ca. 200 to 60 ka, mostly effusive eruptions resulted in peripheral and then central, superimposed lava domes, punctuated by moderately explosive (e.g. Vulcanian) eruptions (Lahitte et al. submitted, Szakács et al. 2015). Occasional larger explosions which are not yet identified may have also occurred. In the past ca. 60-30 ka, violent plinian and phreatomagmatic explosive eruptions became typical (Harangi et al. 2015, Szakács et al. 2015, Karátson et al. 2016), resulting in remarkable geomorphic changes: formation of the the northern "somma" type half-crater rim of Ciomadul Mare (1301 m) and, within that, the central twin-crater (of which Mohos is the older and St. Ana is the younger). A significant part of the pyroclastic products were deposited and well preserved in the Mohos lacustrine succession, and also in proximal and medial settings around the volcano. Moreover, they have also been recovered from medial and distal loessy deposits, terrace formations, even caves (Veres et al. 2017), and also as far as the Dniester delta and the Black Sea (Wulf et al 2016).

The explosive eruptions resulted in thick successions of pyroclastic-fall and -flow deposits in both proximal and medial/distal localities around the volcano. Interestingly, two of the last identified phases of Ciomadul’s young explosive stage show that various types of explosions took place (Karátson et al. 2016). Around 31-32 ka, violent plinian eruptions and pumiceous block-and-ash flows occurred, shaping a "Proto-St. Ana" crater; then, the very last eruption around ca. 28-29 ka ago had a phreatomagmatic character. This latter event was associated with lava dome extrusion possibly from St. Ana vent (Karátson et al. submitted), and resulted eventually in the present-day circular, impressive, ca. 1600 m-large crater which hosts the only primary crater lake in the Carpathians.

Detailed field volcanology, complemented by major element pumice glass geochemistry, optically stimulated luminescence (OSL) and radiocarbon dating as well as Cassignol-Gillot K-Ar ages, helped to refine the succession of the above-mentioned extrusive and explosive 24 events (Karátson et al. 2016, Lahitte et al. submitted). Moreover, advanced DEM analysis along with the obtained new age data (Karátson et al. submitted) made it possible to calculate lava dome volumes and extrusive rates over the life time of the volcano. Overall, the detailed volcanic stratigraphy, strengthtened by the high-precision dating, is a highly helpful tool in detecting paleo-environmental changes, especially for the past 50-60 ka.

References Fielitz W, Seghedi I (2005) Late Miocene-Quaternary Volcanism, Tectonics and Drainage System Evolution on the East Carpathians, Romania. In: Cloetingh S et al. (eds) Special Volume Fourth Stephan Müller Conference of the EGU on Geodynamic and Tectonic Evolution of the Carpathian Arc and its Foreland. Tectonophys 410: 111–136. Harangi Sz, Lukács R, Schmitt AK, Dunkl I, Molnár K, Kiss B, Seghedi I, Novothny Á, Molnár M (2015) Constraints on the timing of Quaternary volcanism and duration of magma residence at Ciomadul volcano, east–central Europe, from combined U–Th/He and U–Th zircon geochronology. J Volcanol Geotherm Res 301: 66–80. Karátson D, Wulf S, Veres D, Magyari EK, Gertisser R, Timar-Gabor A, Novothny Á, Telbisz T, Szalai Z, Appelt O, Bormann M, Jánosi Cs, Hubay K, Schäbitz F (2016) The latest explosive eruptions of Ciomadul (Csomád) volcano, East Carpathians – A tephrostratigraphic approach for the 51–29 ka BP time interval. J Volcanol Geotherm Res 319: 29-51. Karátson D, Veres D, Wulf S, Gertisser R, Magyari EK, Bormann M (2017) The youngest volcanic eruptions in East-Central Europe—new findings from the Ciomadul lava dome complex, East Carpathians, Romania. Geology Today 33/2: 60-65. Karátson D, Telbisz T, Dibacto S, Lahitte P, Szakács A, Veres D, Gertisser R, Jánosi Cs, Timár G (submitted) Eruptive history of the Late Quaternary Ciomadul (Csomád) volcano, East Carpathians II: lava extrusion rates constrained by digital elevation model (DEM) volumetry and radiometric dating. Bull Volcanol. Lahitte P, Dibacto S, Karátson D, Gertisser R, Veres D (submitted) Eruptive history of the Late Quaternary Ciomadul (Csomád) volcano, East Carpathians I: Timing of lava dome activity constrained by the unspiked K-Ar method. Bull Volcanol. Szakács A, Seghedi I, Pécskay Z, Mirea V (2015) Eruptive history of a low-frequency and low-output rate Pleistocene volcano, Ciomadul, South Harghita Mts., Romania. Bull Volcanol 77. https://doi.org/10.1007/s00445-014-0894-7 Veres D, Cosac M, Schmidt C., Murătoreanu G, Hambach U, Hubay K, Wulf S, Karátson D. (2017 online first): New chronological constraints for Middle Palaeolithic (MIS 6/5-3) cave sequences in Eastern Transylvania, Romania. - Quaternary International. DOI: http://doi.org/10.1016/j.quaint.2017.07.015 Wulf S, Fedorowicz S, Veres D, Lanczont M, Karátson D, Gertisser R, Bormann M, Magyari EK, Appelt O, Hambach U, Gozhyk PF (2016) The ‘Roxolany Tephra’ (Ukraine) − new evidence for an origin from Ciomadul volcano, East Carpathians. J Quaternary Sci 31: 565-576.

25

Keynote 6

Keynote 6 in Oral session 6: 28.06.2018, 08:30-09:00

Improving our understanding of Southeast Asian volcanic eruption histories, with an emphasis on Sumatra (Indonesia) 1 1 1 CAROLINE BOUVET DE MAISONNEUVE , OLGA BERGAL-KUVIKAS , MARCUS PHUA , KYLE 1 1 1 1 1 BRADLEY , JEFFREY OALMANN , STEFFEN EISELE , FRANCESCA FORNI , NUR FAIRUZ RAZALI , 2 2 RIZALDI PUTRA , RIFAI HAMDI 1 Asian School of the Environment, Nanyang Technological University, Singapore 2 Universitas Negeri Padang, Indonesia Contact: [email protected]

Improving our knowledge of volcanic eruption histories in Southeast Asia is important for a number of factors, the most obvious of which is regional hazards. Southeast Asia hosts ~750 volcanoes (70 of which have erupted in the past century) and is home to a population of ~600 Million. In Indonesia, for example, ~30% of the population lives within 30 km from a Holocene volcano. Another important factor is that Southeast Asian volcanoes are dominantly located close to the equator. Large volcanic eruptions that send ash into the stratosphere have particularly global impacts on climate when they occur in equatorial to tropical regions because the ash and aerosols released propagate into both hemispheres.

We review the current knowledge about Southeast Asian volcanoes and their eruption histories, and focus on identifying tephrochronologic markers in order to further future paleoclimate and volcanological studies. In parallel, we expand the current knowledge with a tephrostratigraphy study in Sumatra (Indonesia) in order to reconstruct the eruptive history of this particularly understudied but yet hazardous region.

143 volcanoes in Southeast Asia have been classified as Large Calderas (41) and Well- Plugged Stratocones (102) by Whelley et al. (2015) and thus have or are likely to have produced large explosive eruptions with a Volcano Explosivity Index (VEI) of 5-8. Only 26 such eruptions have known ages, spanning from 1.2 Ma to 1991 AD. Fewer have geochemical data that can be used for tephrostratigraphic correlations. Large explosive eruptions from Sumatran volcanoes are generally very silicic (dacitic to rhyolitic), while those from Javanese volcanoes are intermediate (andesites) and those from the Sunda-Banda Arc are mafic (basalts to basaltic-andesites), reflecting the gradual eastward change in geodynamic parameters. Eruptions from the Philippines range in composition from basaltic- andesites to dacites. Along-arc we find that Y contents and 86/87Sr ratios vary consistently and are thus good discriminators of volcanic sources. The Young (75 ka) and Old (~800 ka) Toba Tuffs are frequently used as tephrochronological markers given their widespread occurrence and detailed characterization. However, a closer look at Sumatran volcanics reveals other large caldera-forming eruptions with potentially similar ages. Determining the age and geochemical characteristics of other unstudied calderas will greatly enhance our understanding of the frequencies of such events and enable solid correlations with tephra layers found in distal locations.

26

Keynote 7

Keynote 7 in Oral session 7: 28.06.2018, 11:00-11:30

Bandelier Tuff (1.24 Ma) from the Valles caldera in New Mexico discovered in southwestern Canada: a career-long problem solved 1 JOHN WESTGATE 1 Earth Sciences, University of Toronto, Canada Contact: [email protected]

Integrated field and laboratory methods were key to solving the source of the 3 m-thick tephra bed near Duncairn, Saskatchewan, Canada, which has long remained a mystery. An unusually low CaO content in its glass shards denies a source in the nearby Yellowstone volcanic field. Recent analysis of a tephra bed from the La Sal Mountains of Utah, U.S.A., with a very similar glass chemistry suggests a more southerly source. Comprehensive characterization of these two distal tephra beds, including grain size, mineral assemblage, major- and trace-element composition of glass, paleomagnetism and fission-track dating, in conjunction with analyses of samples collected near the Valles caldera, New Mexico, show that the source is the volcanic field centered in the Jemez Mountains of New Mexico, requiring a trajectory of northward tephra dispersal over a distance of ~ 1500 km. The evidence at hand indicates the proximal correlative of the Duncairn and La Sal Mts tephra beds is the plinian and possibly co-ignimbritic tephra of the 1.24 Ma Tshirege Member of the Bandelier Tuff, derived from the Valles caldera. The tephra dispersal direction can be explained by a deep southward penetration of the jet stream into southwestern U.S.A. and its northward return into Canada.

27

Oral presentations Oral session 1

O 1.1 in Oral session 1: 25.06.2018, 09:00-09:15

Tracing Marine Cryptotephras in the North Atlantic during the Last Glacial Period 1 2 3 2 PETER ABBOTT , ADAM GRIGGS , ANNA BOURNE , SIWAN DAVIES 1 Institute of Geological Sciences, University of Bern, Switzerland 2 Department of Geography, Swansea University, UK 3 Geography and Environment, University of Southampton, UK Contact: [email protected]

Tephrochronology is a powerful technique that can be utilised for the independent correlation and synchronisation of disparate palaeoclimatic records from different depositional environments. There is a high potential to utilise this technique to integrate ice, marine and terrestrial records to study climatic phasing within the North Atlantic region due to the high eruptive frequency of Icelandic volcanic systems. However, until now North Atlantic marine records have been relatively understudied. Here we report on investigations to define a tephra framework integrating new studies of cryptotephra horizons within a wide network of North Atlantic marine cores with horizons identified in prior work.

Tephrochronological investigations were conducted on 13 marine sequences from a range of North Atlantic locations and depositional settings using cryptotephra extraction techniques, including density and magnetic separation, to gain high resolution glass shard concentration profiles and rigorous single-shard major element geochemical analysis to characterise identified deposits. Cryptotephras with an Icelandic source were identified in many records and displayed diversity in shard concentration profiles and the geochemical homogeneity/heterogeneity of shards within the deposits. These differences reflect spatial and temporal variability in the operation of a range of transport processes, e.g. airfall, sea-ice and iceberg rafting, and post-depositional processes, e.g. bioturbation and secondary redeposition. The operation of these processes within the marine environment can potentially impart a temporal delay on tephra deposition and hamper the placement of the isochron, therefore, it is crucial to assess their influence. To aid this assessment a range of deposit types with common transport and depositional histories have been defined. Spatial patterns in the occurrence of these deposit types have been detected, the dominant controls at different sites explored and key regions of the North Atlantic with a greater likelihood for preserving isochronous deposits identified.

Isochronous horizons were identified in cores from a large sector of the North Atlantic to the south and east of Iceland, with a key area to the southeast only preserving isochronous horizons. Ice-rafting deposition of tephra and an interplay between the high eruptive frequency of Iceland and relatively lower sedimentation rates can create some complex tephrostratigraphies in the North Atlantic, emphasising the necessity to fully assess all tephra deposits. Overall, a tephra framework for the last glacial period of 14 isochronous marine cryptotephras could be defined. In addition, several significant geochemical populations that may derive single volcanic eruptions were isolated, however, further investigations are required to determine if they were deposited isochronously. The framework is dominated by horizons with a basaltic composition, predominantly sourced from the Icelandic Grímsvötn volcanic system but horizons with Katla, Hekla, Kverkfjöll, Veidivötn and Vestmannaeyjar like compositions have also been isolated. The most widespread deposit is the rhyolitic phase of North Atlantic Ash Zone II, identified in 9 of the marine sequences and providing a direct tie- line to the Greenland ice-cores records, and the depositional extent of the Faroe Marine Ash Zone II has been extended into the Nordic Sea. This framework now has the potential to 28 underpin the correlation of the marine records to the Greenland ice-core records and European terrestrial sequences.

O 1.2 in Oral session 1: 25.06.2018, 09:15-09:30

The Greenland Ice-Core Tephra Record – potential for correlation and insights into Icelandic volcanism. 1 2 3 4 ANNA BOURNE , SIWAN DAVIES , PETER ABBOTT , ANDERS SVENSSON 1 Geography and Environment, University of Southampton, Southampton, UK 2 Department of Geography, College of Science, Swansea University, Swansea, UK 3 Institute of Geological Sciences, University of Bern, Bern, Switzerland 4 Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Denmark Contact: [email protected]

The Greenland ice-core records provide a master record of past climate changes through the last glacial period and are also an excellent record of past volcanism with both volcanic aerosol (ice acidity and sulphate records) and tephra particulate matter (or glass shards) preserved in the ice. However, only the volcanic glass shards allow the geochemical identification of the volcanic source and their employment as isochronous marker horizons between disparate archives. Over 300 tephra deposits have been identified in NGRIP, NEEM and GRIP and contribute towards the production of a Greenland tephra framework that extends over the last 130ka. The majority of deposits are preserved in cryptotephra form and continuous sampling of the NGRIP ice-core between 25-50ka allows an initial assessment of volcanic frequency during the last glacial period. A total of 88 individual volcanic events are recorded during this time period. Basaltic composition tephras dominate the records and indicate frequent eruptions from the Grimsvötn, Katla and Kverkfjöll volcanoes in Iceland. An assessment of the frequency of eruptions from different volcanic centres will be made and links to any climatic forcing discussed. Those tephra layers that are most useful for correlation to other records will also be discussed.

O 1.3 in Oral session 1: 25.06.2018, 09:30-09:45

An encouraging tephrostratigraphy in southernmost Sweden: results from Körslättamossen 1 1 SIMON LARSSON , STEFAN WASTEGÅRD 1 Department of Physical Geography, Stockholm University, Sweden Contact: [email protected]

Tephrochronology has the potential to establish precise linkages between palaeoclimate archives from different study sites on up to hemispherical scales (e.g. Lane et al. 2017, van der Bilt et al. 2017), and is especially useful to investigate the timing and spatial development of rapid climate shifts such as those in the North Atlantic region during the LGIT (e.g. Lowe 2001, Lane et al. 2011, Davies et al. 2012). For this very purpose, a tephra study of the Körslättamossen fen in Scania, southern Sweden, has been carried out and yielded encouraging results.

The site has previously been studied by Hammarlund & Lemdahl (1994) and was sampled for tephra investigation as well as new proxy analyses in 2016. A close correlation to the previous study is evident from stratigraphy and carbon analysis. Five cryptotephra horizons were detected, four of which have been geochemically analysed by EPMA and identified as the Hässeldalen Tephra, the Vedde Ash, the Laacher See Tephra, and a Borrobol-type 29 tephra. The fifth tephra, placed between the LST and the Borrobol-type tephra, is yet unidentified.

The cryptotephras found enable correlation of previous as well as upcoming proxy results to other sites in the region in order to approach the issue of synchroneity versus time transgression of the LGIT climate shifts. The occurrence of the LST in Körslättamossen is the first geochemically confirmed finding of the LST on Swedish mainland and expands the dispersal area of this tephra further northwest than previously suggested (Larsson & Wastegård, 2018).

References Davies, S.M., Abbott, P.M., Pearce, N.J.G., Wastegård, S. & Blockley, S.P.E., 2012: Integrating the INTIMATE records using tephrochronology: rising to the challenge. Quaternary Science Reviews, vol. 36, pp. 11–27. Hammarlund, D. & Lemdahl, G., 1994: A Late Weichselian stable isotope stratigraphy compared with biostratigraphical data: a case study from southern Sweden. Journal of Quaternary Science, vol. 9, pp. 13–31. Lane, C.S., Blockley, S.P.E., Ramsey, C.B. & Lotter, A.F., 2011: Tephrochronology and absolute centennial scale synchronisation of European and Greenland records for the last glacial to interglacial transition: A case study of Soppensee and NGRIP. Quaternary International, vol. 246, pp. 145–156. Lane, C.S., Lowe, D.J., Blockley, S.P.E., Suzuki, T. & Smith, V.C., 2017: Advancing tephrochronology as a global dating tool: Applications in volcanology, archaeology, and palaeoclimatic research. Quaternary Geochronology, vol. 40, pp. 1–7. Larsson, S.A. & Wastegård, S., 2018: The Laacher See Tephra discovered in southernmost Sweden. Journal of Quaternary Science, DOI 10.1002/jqs.3033. Lowe, J.J., 2001: Abrupt climatic changes in Europe during the last glacial–interglacial transition: the potential for testing hypotheses on the synchroneity of climatic events using tephrochronology. Global and Planetary Change, vol. 30, pp. 73–84. van der Bilt, W.G.M., Lane, C.S. & Bakke, J., 2017: Ultra-distal Kamchatkan ash on Arctic Svalbard: Towards hemispheric cryptotephra correlation. Quaternary Science Reviews, vol. 164, pp. 230–235.

O 1.4 in Oral session 1: 25.06.2018, 09:45-10:00

The Glacier Peak ash in Scotland 1 2 SEAN PYNE-O'DONNELL , BRITTA JENSEN 1 Queen's University Belfast, United Kingdom 2 University of Alberta, Canada Contact: [email protected]

The Lateglacial period (~14.7 – 11.7 cal. ka BP) eruptive stage of Glacier Peak in the Cascade Range deposited a number of ash layers (tephras) in quick succession, forming visible event-stratigraphic marker layers (isochrons) across much of western North America. Geochemically distinctive microscopic glass shards from one of the most explosive eruptions of this stage remain detectible in a ‘cryptotephra’ layer (not visible in stratigraphy to the naked eye) of rhyolitic composition in lake sediments on the NE Atlantic Seaboard, where it is dated to 13.74 – 13.45 cal. ka BP.

Here, we report the first trans-Atlantic detection of Glacier Peak cryptotephra in a Lateglacial lake site in western Scotland, ~7000 km from source. At this location on the Isle of Skye, the Glacier Peak shares a crowded tephrostratigraphy with two well-documented cryptotephra layers of likely Icelandic origin: the Borrobol Tephra (14.19–14.00 cal. ka BP) and the geochemically equivalent Penifiler Tephra (14.06–13.81 cal. ka BP) which occur in a number of terrestrial Lateglacial sequences in Scotland, Scandinavia and Germany. Recent detection of cryptotephra layers of Borrobol-type composition in the Greenland ice-core stratigraphy may additionally correlate to these terrestrial deposits. 30

Previous tephra work at the present site, as well as other localities, had not identified shards of Glacier Peak composition. This may be due to masking of such ultra-distal layers by the relatively greater concentrations of the closely preceding, and thus stratigraphically overshadowing, Penifiler and Borrobol tephras which often exhibit wide post-peak shard distributions often attributed to reworking, though additional inputs from the Icelandic source have also been suggested. However, the use of 0.5 cm contiguous stratigraphic sampling and off-peak geochemical analysis in this study resolves previously unseen shard concentration variations within these distribution tails which are consistent with additional tephra layers and which are shown to contain a relatively greater proportion of Glacier Peak composition.

It is likely that other sedimentary sequences with faster accumulation rates will allow better stratigraphic distinction of the Glacier Peak layer from the Penifiler tephra. Additionally, the Glacier Peak may be present elsewhere in the European tephrostratigraphy in sequences where the Borrobol and Penifiler tephras were not deposited, and consequently where it will be less obscured.

The introduction of the well dated Glacier Peak isochron into the regional tephrostratigraphy of Scotland should aid in constraining local age models. It should also permit direct trans- Atlantic correlation of sedimentary sequences for the mid-Lateglacial period, which was characterised by abrupt and short-lived climate oscillations. Accurate assessment of the relative timings of such palaeoclimate events is key to determining causal forcing mechanisms throughout the North Atlantic region.

O 1.5 in Oral session 1: 25.06.2018, 10:00-10:15

Tephrochronology as a tool in volcanology: Early Holocene explosive volcanism in Iceland 1 1 1 1 ESTHER RUTH GUDMUNDSDÓTTIR , GUDRÚN LARSEN , JÓN EIRÍKSSON , ÓLAFUR INGÓLFSSON , 2 SVANTE BJÖRCK 1 Institute of Earth Sciences, University of Iceland 2 Department of Geology, Lund University, Sweden Contact: [email protected]

In Iceland eruption frequency is high and is estimated to exceed 20 eruptions per century on average during the Holocene. The majority of the eruptions are mafic (~90%) and predominantly explosive (~70%). The dominating explosive volcanism in Iceland allows for the history and behaviour of volcanic provinces to be studied in detail through tephra stratigraphy.

The tephra stratigraphy of the mid and late Holocene in Iceland is relatively well known, mostly based on studies of numerous soil profiles across the country. The focus of this study is to obtain a more comprehensive knowledge and information on early Holocene tephra stratigraphy and eruption history. For this purpose, high-resolution records from soil, lacustrine and marine archives extending beyond 7200 years have been studied.

The aim of the study is to compare the early Holocene explosive volcanic activity and behaviour of volcanic systems to the mid and late Holocene activity. Research questions concern, i) which volcanoes were active, ii) what was the level of their activity and iii) is there periodicity in the explosive volcanic activity as is apparent in the mid and late Holocene records. In addition, the major element chemistry of the tephra layers will be used to obtain information on compositional variations of magma within selected volcanic systems.

31

O 1.6 in Oral session 1: 25.06.2018, 10:15-10:30

The ELSA-Tephra-Stack-2018 1 FRANK SIROCKO , MICHAEL FÖRSTER 1 Institute for Geoscience, University Mainz Contact: [email protected]

60 open and infilled maar lakes of the West Eifel Volcanic Field in Germany have been drilled with up to 150 m long sediment cores by the ELSA Project (Eifel Laminated Sediment Archive). The sediments cover the last 500,000 years and show numerous tephra layers (Förster & Sirocko, 2016). Cores are dated with 8 different methods. Precise dates for the last glacial cycle come from a tuning of the sediment organic carbon content to the Greenland interstadial succession (Sirocko et al. 2016) and allow highest resolution comparison of the timing of the Eifel volcanic activity to the Greenland/North Atlantic/European climate (Fig. 1). The Figure contains some new results not shown in Förster & Sirocko (2016), because it includes two new cores from the silted up maar of Auel. These cores reveal that the Wartgesberg Tephra was not only one eruption, but three within one millennia. It also shows a tephra at 26.000 BP, which comes close to the Eltville Tephra, but is geochemically not fully analyzed yet. The age of this tephra is also still preliminary. However, when looking at the whole Tephra Stack, we do not see a clear relation to the climate evolution of central Europe, but one might see an indication that volcanic activity in the Eifel was mostly active during times of mass changes in the global ice volume/sea level.

Fig. 1. Synthesis of the updated ELSA-Tephra-Stack-2016 with the Greenland ice interstadial succession and the updated ELSA-Dust-Stack-2016 (Seelos et al., 2009).

References Förster, M.W. & Sirocko, F. (2016). Volcanic activity in the Eifel during the last 500 000 years: The ELSA-Tephra-Stack. Global and Planetary Change 142, 100-107. Seelos, K., Sirocko, F. and Dietrich, S. (2009). A continuous high-resolution dust record or the reconstruction of wind systems in central Europe (Eifel, Western Germany) over the past 133 ka, Geophysical Research Letters, 36, L20712, doi:10.1029/2009GL039716. 32

Sirocko, F.; Knapp, H.; Dreher, F.; Förster, M.W.; Albert, J.J; Brunck, H.; Veres, D.; Dietrich, S.; Zech, M.; Hambach, U.; Röhner, M.; Rudert, S.; Schwiebus, K.; Adams, C.; Sigl, P. (2016). Landscape evolution and volcanic activity in the Eifel; reconstruction from maar sediments of the last 70.000 years. Global and Planetary Change 142, 108-135.

Oral session 2

O 2.1 in Oral session 2: 25.06.2018, 11:00-11:15

The Eltville Tephra (Western Europe): distribution and timing for an important Western European stratigraphic marker 1 1 1 2 FRANK LEHMKUHL , CHRISTIAN ZEEDEN , JÖRG ZENS , STEFAN VLAMINCK 1 Department of Geography, RWTH Aachen University, Germany 2 DepartmeDepartment of Geography, RWTH Aachen University, Germany Contact: [email protected]

Within the western European loess belt the Eltville Tephra (ET) is an important stratigraphic marker bed (See Figure 1). The ET is found close to the boundary between loess deposits attributed to the regional Last Glacial Maximum (LGM, max. extent of Scandinavian ice sheet) and those associated with the “terrestrial” LGM, characterized by highest degree of aridity and coldness.

Zens et al. (2017) show that luminescence data from 87 different datasets on the ET provide ages between 13.5 and 49.6 ka. Based on individual sections, the deposition of the ET was supposed to have taken place between 20 and 23 ka, while new luminescence ages bracketing this volcanic ash layer date to 23.2 -25.6 ka. This is in agreement with direct ages from the ET, yielding 24.1+1.9 ka (quartz) and 24.3 + 1.8 ka (pIRIR290). In addition, there is a peak of volcanic minerals in the Dehner Maar core around 24.3 ka. This age is older as previously suggested for the ET, but fits better to stratigraphic and paleoenvironmental evidence.

The ET was deposited during phases of strong aeolian activity of the Greenland Stadial 3. This is in agreement with thicknesses of up to 20 cm for the entire ET sequence found in the surroundings of the Eifel Mountains. Additionally, Zens et al. (2017) provide a correlation between the ET and tephra layers recognized in the Eifel Maar lake cores. Results of heavy minerals from the Dehner Maar (Römer et at., 2016) show varying wind systems and strong easterly wind directions during this time. Therefore, also the distribution of the ET in both directions, west and east of the Eifel volcanic fields, can be explained.

References Zens, J., Zeeden, C., Römer, W., Fuchs, M., Lehmkuhl, F. (2017): The Eltville Tephra (Western Europe) age revised: integrating stratigraphic and dating information from different Last Glacial loess localities. - Palaeogeography, Palaeoclimatology, Palaeoecology 466: 240-251. Römer, W., Lehmkuhl, F., Sirocko, F. (2016): Late Pleistocene aeolian dust provenances and wind direction changes reconstructed by heavy mineral analysis of the sediments of the Dehner dry maar (Eifel, Germany). Global and Planetary Change 147: 25-39. 33

Figure 1: Distribution map of the Eltville Tephra. The black dots show undated loess sections with reported occurrence of the ET; black triangles indicate dated sections. The black lobe shows the spatial distribution. Data source and further details: see Zens et al. (2017).

O 2.2 in Oral session 2: 25.06.2018, 11:15-11:30

The cryptotephra record of the Marine Isotope Stage 12 to 9 interval (460–305 ka) at Tenaghi Philippon, Greece: Exploring chronological markers for the Middle Pleistocene of the Mediterranean region 1 2 3 4 POLINA VAKHRAMEEVA , ANDREAS KOUTSODENDRIS , SABINE WULF , WILLIAM J. FLETCHER , 5 6 1 OONA APPELT , MARIA KNIPPING , JÖRG PROSS 1 Institute of Earth Sciences, Heidelberg University 2 nstitute of Earth Sciences, Heidelberg University 3 Department of Geography, University of Portsmouth 4 Quaternary Environments and Geoarchaeology, Geography, School of Environment and Development, University of Manchester 5 Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences 6 Institute of Botany, University of Hohenheim Contact: [email protected]

Precise chronologies that allow direct correlation of paleoclimate archives are a prerequisite for deciphering the spatiotemporal characteristics of short-term climate variability. Such chronologies can be established through the analysis of (crypto)tephra layers that are preserved in the respective sedimentary archives. Here we explore the yet untapped tephrochronological potential of the Eastern Mediterranean region for the Middle Pleistocene, specifically for the interval spanning Marine Isotope Stages (MIS) 12–9 (460–305 ka). High- resolution cryptotephra analysis was conducted on peat cores spanning the MIS 12–9 interval that have been recovered from the iconic climate archive of Tenaghi Philippon, NE Greece. Thirty-six primary cryptotephra layers were identified, and major- and trace-element analyses of single glass shards were performed in order to correlate the cryptotephras with their eruptive sources. The glass compositions indicate that three cryptotephras originate from Italy and seventeen from the Aegean Arc, while the provenance of sixteen layers 34 remains yet unknown. Two cryptotephra horizons are correlated with the Cape Therma 1 and Cape Therma 2 eruptions from Santorini, which makes them the first distal tephra findings for these eruptive events. The abundance of cryptotephras that could not yet be attributed to specific volcanoes and eruptions reflects the considerable knowledge gap regarding the geochronology and geochemistry of proximal tephra deposits from the Middle Pleistocene of the Central and Eastern Mediterranean regions. Due to the lack of well-dated Middle Pleistocene eruptions, we provide age estimates for all cryptotephra layers identified in the MIS 12–9 interval at Tenaghi Philippon based on high-resolution pollen data from the same cores. The high number of cryptotephras from multiple sources as recorded in the MIS 12–9 interval at Tenaghi Philippon highlight the key role of this archive for linking tephrostratigraphical lattices for the Middle Pleistocene of the Central and Eastern Mediterranean regions.

O 2.3 in Oral session 2: 25.06.2018, 11:30-11:45

New results from São Miguel, Azores Islands, confirming the links between proximal tephras and distal sites in mainland Europe 1 1 STEFAN WASTEGÅRD , HANS JOHANSSON 1 Stockholm University, Sweden Contact: [email protected]

The Azores archipelago is one of the most active volcanic areas in the North Atlantic region, with approximately 30 eruptions during the last 600 years. The geochemical composition of associated tephra-derived glass is, however, not well characterized. It has recently been suggested that trachytic tephras found in distal areas such as North Africa, the British Isles and Greenland may derive from eruptions on the Azores, but proximal data from the Azores are scarce and the correlations have been tentative at best. These trachytic tephras lie clearly outside the geochemical Icelandic province and have a potential to improve the European tephrostratigraphy/tephrochronology framework, especially in sites in south and central Europe where tephras from more than one European volcanic system have been found (e.g. Lane et al., 2011). Analyses of tephra glass from five mid and late Holocene eruptions on the Azores Islands were presented by Johansson et al. (2017) and there is a striking geochemical similarity between trachytic tephras from volcanoes on the São Miguel island and cryptotephras found on Ireland (e.g. Chambers et al., 2004), and especially with eruptives from the Furnas volcano. Eruptives from the active stratovolcanoes on São Miguel: Sete Cidades, Fogo and Furnas, can be distinguished from one another using major element geochemistry, for example in biplots of FeO vs. TiO2. EPMA analyses of samples taken in 2018 confirm and strengthen these links and we can also correlate a previously unsourced tephra found in a Swedish bog with an eruption of the Sete Cidades volcano ca 3600 cal BP. We conclude that trachytic tephras erupted from explosive eruptions on São Miguel have a potential to contribute to the construction of a European-wide tephrostratigraphic framework.

Refrences Chambers, F.M., Daniell, J.R.G., Hunt, J.B., Molloy, K., O'Connell, M., 2004. Tephrostratigraphy of An Loch Mór, Inis Oírr, western Ireland: implications for Holocene tephrochronology in the northeastern Atlantic region. The Holocene 14, 703-720. Johansson, H., Lind, E.M., Wastegård, S., 2017. Compositions of glass in proximal tephras from eruptions in the Azores archipelago and their links with distal sites in Ireland. Quaternary Geochronology 40,120-128. Lane, C.S., Andrič, M., Cullen, V.L., Blockley, S.P., 2011. The occurrence of distal Icelandic and Italian tephra in the Lateglacial of Lake Bled, Slovenia. Quaternary Science Reviews 30, 1013-1018.

35

Sampling the Sete Cidades P2 tephra (ca. 3600 cal BP), March 2018. Photo: Stefan Wastegård

O 2.4 in Oral session 2: 25.06.2018, 11:45-12:00

Late glacial – early Holocene Cryptotephra from the Falkland Islands (Malvinas) 1 1 1 ALI MONTEATH , PAUL HUGHES , ROB SCAIFE 1 University of Southampton, United Kingdom Contact: [email protected]

Studies of cryptotephra deposits (non visible ash) in the northern hemisphere provide valuable chronological isochrons, and insights into long-distance transport of tephra. However, few cryptotephra records exist from the southern hemisphere despite strong atmospheric circulation patterns and frequent explosive volcansim. Here we present late glacial – early Holocene tephrostratigraphy (16,000-6,000 cal yr BP) from Hooker’s Point, an exposed peat cliff on east Falkland Island. Primary cryptotephra deposits are linked with the late glacial Reclus R1 tephra (ca. 14,800 cal yr BP), and the early Holocene MB1 tephra, derived from Mt. Burney (ca. 9,500 cal yr BP). Further peaks in tephra abundance are chemically heterogeneous with low analytical totals, low Na2O and high SiO2, suggesting they are formed of weathered detrital glass. These shards are likely to have been reworked from primary deposits in the South American mainland by strong Southern Westerly winds. A reduction in shard abundance that coincides with the Antarctic Cold Reversal and Younger Dryas climatic events may reflect changes in the strength or positioning of the Southern Westerlies during this time period.

36

O 2.5 in Oral session 2: 25.06.2018, 12:00-12:15

Ash from the early Holocene Changbaishan eruption: A new marker horizon across East Asia 1 1 CHUNQING SUN , JIAQI LIU 1 Institute of Geology and Geophysics, Chinese Academy of Sciences, China Contact: [email protected]

The Holocene eruptions of Changbaishan volcano in Northeast China are poorly dated except for the well-dated Millennium eruption (ME). Less precise age estimates for these eruptions present problems for the reconstruction of eruptive sequence of the volcano. The Qixiangzhan eruption (QE) is a major controversial event in terms of eruptive timing (from ~88 kyr to ~4 kyr) and style (effusive or explosive). The comendite from this eruption recorded a geomagnetic field excursion; however, imprecise age estimates for the QE induced incorrect correlations with some certain excursion events. In this study, a visible early Holocene tephra was identified in Yuanchi Lake, ~30 km east of the Changbaishan volcanic vent, and was dated to an age of 8831-8100 cal yr BP using Bayesian age modelling. Glass shard compositions enable the correlation of this tephra with the poorly dated QE, and the tephra (SG14-1058) recorded in Lake Suigetsu, in central Japan. These correlations confirm that the QE was explosive, and that the ash from Qixiangzhan eruption (QEA) can serve as an important early Holocene marker bed across East Asia. In addition, we proposed an age of ~8100 cal yr BP to the QE based on the precise date of the Suigetsu SG14-1058 tephra recorded in Lake Suigetsu. Our results also indicate that a geomagnetic field excursion at ~8100 cal yr BP was recorded in the Qixiangzhan comendite, Changbaishan volcano.

O 2.6 in Oral session 2: 25.06.2018, 12:15-12:30

100- kyr cyclicity in volcanic ash emplacement: evidence from a 1.1 Myr tephra record from the Nothwest Pacific 1 2 2 2 JULIE CHRISTIN SCHINDLBECK , MARION JEGEN , ARMIN FREUNDT , STEFFEN KUTTEROLF , 3 4 3 SUSANNE STRAUB , MARYLINE MLENECK-VAUTRAVERS , JERRY MCMANUS 1 Institute of Earth Sciences, University of Heidelberg 2 GEOMAR Helmholtz Centre for Ocean Research Kiel 3 Lamont-Doherty Earth Observatory of Columbia University 4 Department of Earth Sciences, University of Cambridge Contact: [email protected]

Systematic changes in eruption frequencies since the last glacial maximum in Iceland and elsewhere suggest that deglaciation may have an effect on volcanism. Nevertheless, the existence of causal links between volcanism and Earth’s climate remains highly controversial, partly because most related terrestrial eruptive event studies only cover one glacial cycle.

Long records extending across several glacial cycles are particularly available from marine sediment profiles in which the distribution of tephras combined with high-resolution age models documents the temporal changes in eruption frequencies, mostly of explosive arc volcanism.

In our study we investigated the tephra record of IODP Hole U1437B (northwest Pacific), which records 162 explosive eruptions within the last 1.1 Myr.

A spectral analysis of the dataset yields a statistically significant spectral peak at the ~100 kyr period, which dominates the global climate cycles since the Middle Pleistocene. A time- 37 domain analysis of the entire eruption and δ18O record of benthic foraminifera as climate/sea level proxy shows that volcanism peaks after the glacial maximum and 13±2 kyr before the δ18O minimum right at the glacial/interglacial transition. The correlation is especially good for the last 0.7 Myr after the Middle Pleistocene Transition, whereas the correlation between 0.7 and 1.1 Ma during the MPT is relatively poor because then the 100 kyr signal, which persists in the tephra record, is comparatively weak in the δ18O record. This means that the observed correlation over the entire record is strongly dominated by the good correlation post-MPT. The observed correlation strongly suggests that partial melting of the large ice sheets triggered an increase in volcanism. The persistence of the strong 100 kyr periodicity in the tephra record well into MPT times suggests that this causal link persisted to times >0.7 Ma despite the then weak 100 kyr periodicity in the δ18O spectrum.

Oral session 3

O 3.1 in Oral session 3: 25.06.2018, 16:30-16:45

The value of disrupted, distorted, disturbed and re-deposited tephra sequences: from classical tephrochronology to a tephra science of past environments. 1 1 2 3 ANDREW DUGMORE , ANTHONY NEWTON , RICHARD STREETER , NICK CUTLER 1 School of GeoSciences, University of Edinburgh, United Kingdom 2 School of Geography and Sustainable development, University of St Andrews, United Kingdom 3 School of Geography, Politics & Sociology, University of Newcastle, United Kingdom Contact: [email protected]

Classical tephrochronology has made many important contributions to our understanding of volcanic eruptions, past environments and societies. It is apparent that tephra layers and identified tephra deposits can be used in a variety of ways to understand chronology and other aspects of the past. However, classical tephrochronology can be part of a more wide ranging tephra science. Tephra layers can define isochrons. In addition, as freshly-fallen tephra deposits become a part of the stratigraphic record, the thickness and morphology of the layers changes, reflecting Earth surface and atmospheric processes and the structure of vegetation communities. Thus, the form of the tephra layers themselves may contain proxy records of past surface environments and, when part of a sequence, indicate trajectories of change. Longer-term, post depositional/post stratigraphic entrainment changes can also result in further modification of tephra layers within the stratigraphic record, and the creation of further proxy records of past environments. For example, layers within soil may be distorted by cryoturbation and layers within glacial ice may be transported long distances and be subject to complex sequences of morphological modification whilst still retaining the same stratigraphic relationships with the ice which formed before and after their deposition. In other situations, the stratigraphic record of initial tephra deposition and layer formation may be completely lost, but in the process yet more aspects of environmental change may be recorded. Pumice may float across oceans, be deposited on shore lines, collected by people, used, and discarded before being finally incorporated into deposits long after the pumice was formed. Environmental processes that affect the tephra record can make the application of classical tephrochronology challenging. However, innovative sources of environmental data can exist within disrupted, distorted, disturbed and re-deposited tephra sequences. As well as developing a wider tephra science for past environments, understanding the processes of tephra layer transformation could also make a vital contribution to a better understanding of the correct interpretation of tephra layers to reconstruct eruption parameters.

38

O 3.2 in Oral session 3: 25.06.2018, 16:45-17:00

Earth-shaking insight from liquefied tephra layers in lakes in central Waikato region, New Zealand: a new tool to evaluate and date palaeoseismicity? 1 1 1 2 3 DAVID J LOWE , REMEDY C LOAME , VICKI G MOON , RICHARD E JOHNSTON , MAX O KLUGER , 4 5 1 6 7 PILAR VILLAMOR , ROLANDO ORENSE , WILLEM P DE LANGE , SIWAN M DAVIES , NIC ROSS , 4 8 MARCUS J VANDERGOES , ANDREW BH REES 1 School of Science (Earth Sciences), University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 2 College of Engineering, Swansea University, Swansea, Wales SA1 8EN, UK 3 MARUM – Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany 28395 4 GNS Science, PO Box 30368, Lower Hutt 5040, New Zealand 5 Department of Civil and Environmental Engineering, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand 6 Department of Geography, Swansea University, Singleton Park, Swansea, Wales SA2 8PP, UK 7 Hamilton Radiology, Gate 1, 11 Thackeray Street, Hamilton 3204, New Zealand 8 School of Geography, Environment, and Earth Science, Victoria University of Wellington, Box 600, Wellington 6140, New Zealand Contact: [email protected]

Liquefaction of lake sediments can be linked to seismicity. However, liquefied volcanic-ash or tephra layers per se have not been reported in lake sediments. Such liquefied tephra layers occur systematically within undeformed organic sediments in ~22,000-year-old lakes in the central Waikato region, North Island, where we have also recently discovered ~25 hidden faults in an area previously thought devoid of active faults. The discovery of sandy injection structures and dikes within Late Pleistocene volcanogenic alluvium (Hinuera Formation) dated at ~21,000 cal. yr BP in the same region indicates that one or more of the hidden faults has been active since then. We therefore hypothesise that the liquefied tephras, showing disruption features equivalent to soft-‘sediment’ deformation structures (SSDS), reflect (palaeo)liquefaction arising from severe shaking from earthquakes generated on faults proximal to the lakes in which the tephras occur, rather than as a consequence of sedimentary processes, forming ‘tephra seismites’. The tephra seismites are unlikely to represent shaking induced by movement on the distant Kerepehi Fault system in the neighbouring Hauraki Basin: many of the lakes in the Hamilton Basin are ≥~40 km from the nearest segments of Kerepehi Fault. Also, we considered activity in the Taupo Volcanic Zone (TVZ) in central North Island but it is even more distant than Kerepehi, and the faults in TVZ tend not to have large ruptures and pervasive pyroclastic deposits in central North Island attenuate the waves. A local source is much more likely on the basis of our preliminary evidence. Our prior records for 84 sediment cores from 12 lakes show that three tephra seismites aged 15.7, 14.0, and 8.0 cal. ka occur in some, but not all, lakes. Computed tomography (CT) and micro-CT scans of new cores have revealed that two more tephras age 17.2 and 7.6 cal. ka have been liquefied (see companion paper by Loame et al.). The tephra seismites include unusual downward-propagated vertical ash-rich injectites and intra-ash voids. The latter have smooth surfaces, indicating that fluidised ash has flowed from the original ash layers, leaving the voids (Fig. 1). Denser than the enclosing fine organic sediments of low permeability, these ash beds on shaking did not become buoyant as occurs in terrestrial settings upon liquefaction but instead were injected downwards to dissipate pore-water pressure, generating the various liquefaction features. That some tephra layers are prone to liquefy with seismic shaking while others remain stable relates to proximity to fault rupture, the nature of the ash layers including their thickness, and their depth of burial. Thus, it is essential to understand the preconditioning factors that initiate liquefaction. We are therefore developing a cross-disciplinary methodology to quantify the spatial extent and intensity of ground shaking by characterizing and mapping the seismites in multiple lake sediment records using CT scanning, and by investigating the initiation of liquefaction in unaltered tephra layers using experimental geotechnical engineering. Our research will enhance general understanding of the mechanical behaviour of tephra deposits subjected to seismic shaking and develop a new methodology for palaeoseismicity for low seismicity 39 areas in New Zealand and globally wherever faults and tephra seismites occur together. It will also allow us to narrow down the frequency, magnitude, and locations of large earthquakes in the Waikato region since ~22 cal. ka, and enable better assessment and prediction of geohazard risks to improve earthquake resistance standards for buildings and infrastructure.

Fig. 1. Image showing (at left) a photo and CT scan of a short lake sediment core (~0.6 m long), and a close-up (at right) illustrating voids and injectites associated with liquefied Rotorua tephra (~15.7 cal. ka).

40

O 3.3 in Oral session 3: 25.06.2018, 17:00-17:15

DNA extraction from paleosols on tephras: insights in the search for ancient DNA from past terrestrial ecosystems 1 2 2 2 YU-TUAN (DOREEN) HUANG , DAVID J. LOWE , RAY CURSONS , HENG ZHANG , G. JOCK 3 2 4 5 CHURCHMAN , LOUIS A. SCHIPPER , NICOLAS J. RAWLENCE , ALAN COOPER , JONATAN 6 KLAMINDER 1 Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden 2 School of Science, University of Waikato, Private Bag 3105, Hamilton, New Zealand 3 School of Agriculture, Food and Wine, University of Adelaide, Adelaide, South Australia 4 Allan Wilson Centre for Molecular Ecology and Evolution, Department of Zoology, University of Otago, Dunedin, New Zealand 5 Australian Centre for Ancient DNA, School of Earth and Environmental Science, University of Adelaide, Adelaide, South Australia 6 Department of Ecology and Environmental Science, Umeå University Contact: [email protected]

Predicting the consequences of climate warming and imminent environmental changes requires an understanding of historical ecosystems and their response to environmental perturbations beyond the timescale of contemporary monitoring programs. Many of paleoclimate and paleoenvironmental studies rely on evidences from ice core, marine and lake sediments, but those matrices do not provide direct detailed insights in terrestrial ecological changes in response to time, climate, and environment.

Buried paleosols developed on sequences of well-dated tephras sequester organic carbon over long time periods. Allophane is a nanocrystalline aluminosilicate clay made up of tiny spherules ~3.5‒5.0 nm in diameter. Our previous work has shown that allophane is able to sequester and protect organic matter from degradation over long time periods through ‘physical’ encasement within nanopores amidst allophane spherules and allophanic nanoaggregates (allophane sphere clusters £ 100 nm in size) and microaggregates (small clusters of allophane nanoaggregates), and by chemical adsorption. Such protection in these paleosols implies that ancient DNA (aDNA) may similarly to be preserved, and its extraction and identification therefore provide a potential means for reconstructing past environments from terrestrial sequences comparable to, for example, phytolith analysis. However, DNA extraction from tephra-derived soil materials is extremely difficult because of (1) the strong bonding between DNA and allophane and (2) the co-extracted humic substances inhibit subsequent DNA analyses. To overcome the difficulties, we developed a new two-step DNA extraction method. This method comprises (1) first extraction using an alkaline buffer and (2) second extraction by acid oxalate solution. For proof of principle, we used synthetic allophane and salmon-sperm DNA to test whether it was possible to extract DNA that was strongly bound to allophane, or encased within nanopores amidst aggregates, using first or second extraction, or both. Our results showed that salmon-sperm DNA was inaccessible (and hence protected) by using the first extraction buffer, and the addition of acid oxalate, which is the second extraction, caused allophane and its nanoaggregates to collapse through dissolution, thus successfully ‘releasing’ the salmon-sperm DNA.

To further test the mobility of DNA in the soil profile (pedon), we performed an experiment in west Greenland where a proglacial paleosol (non-allophanic) soil sequence occurs. We applied known fish DNA (Salvelinus alpinus, arctic char) on the land surface and simulated severe rainfall at the site. The results showed that arctic char DNA was rarely detected at 30 cm depth and the deeper (lower) subsoil horizons were free from surface contamination of arctic char DNA. These findings indicate that the downward leaching of modern DNA is limited in this setting, probably ascribable to the adsorption of DNA by clays in the active surface or upper subsoil horizons.

We next applied the two-step extraction method, and used several commercial DNA extraction kits (GenScript, Zymo Research, and Vivantis Soil DNA Kits), to four natural soils, 41 three with allophane and one with tubular halloysite (an aluminosilicate clay), to ascertain the ability of these methods to extract any environmental DNA that was present in the soils. The commercial kits were ineffectual in our study. However, our two-step process was successful in releasing environmental DNA from both allophanic and non-allophanic soils with high yields obtained. We also found that the DNA extracted from halloysitic soil was more degraded than that from allophanic soils, suggesting that allophane and the allophanic nanoaggregates helped to protect the DNA fragments better than halloysite.

We sequenced the extracted DNA from an allophanic buried soil horizon developed on the c. 9500 cal. year old rhyolitic Rotoma tephra (erupted from Haraharo Complex, Okataina Volcanic Centre, 9472 ± 40 cal. yr BP, 95% age range) near Mt Tarawera in northern New Zealand. Native plant DNA (trnL gene) of Araliaceae (ivy-family) and Myrtaceae (myrtle- family) were recovered from the paleosol, which likely originated from early-mid Holocene plants growing on the soil prior to its burial c. 5500 cal. yr BP by the Whakatane tephra (erupted from Haraharo Complex, Okataina Volcanic Centre, 5542 ± 48 cal. yr BP, 95% age range). Moreover, plant DNA from the current biologically active modern land/soil surface was not detected in the buried paleosols. We will further analyze the taxonomic diversity of plant, animal and insect DNA in the succession of allophanic buried soil horizons on Holocene and late Pleistocene tephras to understand whether aDNA in such paleosols faithfully represents its stratigraphic context by comparing findings with taxonomic information from phytolith and pollen studies undertaken in the same region on different palaeoenvironmental archives. We can connect the different archives using tephrochronology.

O 3.4 in Oral session 3: 25.06.2018, 17:15-17:30

Using CT scanning for reconnaissance and detection of cryptotephras in ~22,000-yr-old lake sediments, central Waikato region, New Zealand 1 1 1 2 REMEDY C. LOAME , DAVID J. LOWE , ADRIAN PITTARI , SIWAN M. DAVIES , CHRISTINA R. 3 4 5 6 MAGILL , MARCUS J. VANDERGOES , ANDREW B.H. REES , NIC ROSS 1 School of Science, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 2 Dept. of Geography, Swansea University, Singleton Park, Swansea, Wales SA2 8PP, UK 3 Department of Environmental Sciences, Macquarie University, St Leonards, NSW 2065, Australia 4 GNS Science, P.O. Box 30368, Lower Hutt 5040, New Zealand 5 School of Geography, Environment, and Earth Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand 6 Hamilton Radiology, Gate 1, Thackeray Street, Hamilton 3204, New Zealand Contact: [email protected]

It is now well established that the detection and analysis of cryptotephras (volcanic glass shard and/or crystal deposits insufficiently concentrated or numerous to be visible as a layer to the naked eye) enable more comprehensive records of explosive volcanic history to be developed than those constructed using visible tephras alone. Although a record of ~35 rhyolitic and andesitic tephra layers, ranging in thickness from ~2 to 110 mm, has been documented from analysis of sediments in lakes aged c. 22,000 cal. years in the central Waikato region of North Island, New Zealand, cryptotephra studies have been limited to only the last ~1800 years. We have therefore begun a new project to develop a more comprehensive record of tephra deposition in the region by finding and analysing cryptotephras in the lake sediments to complement the visible tephra record. Consequently, we retrieved replicate sediment cores totalling 34.7 m in length from three lakes, Kainui, Ngaroto, and Rotokauri, which were formed c. 21,000-23,000 cal. years ago. We applied X- ray computed tomography (CT) scanning to try to develop a time-efficient, cost-effective, and non-destructive method for reliably detecting cryptotephras. The whole (unopened) cores were scanned in one afternoon using a medical CT scanner at a local private clinic (Hamilton 42

Radiology) in Hamilton. Volume reconstructions and image analyses using the Fiji package of ImageJ software revealed numerous potential cryptotephra deposits, significantly increasing the number of observable deposits compared with findings from descriptive logs and associated photographs of the same cores when opened. The information from visual analyses is supported by variations in the average values of Hounsfield Units (HU) measured during CT scanning. HUs represent the relative density of materials, with cryptotephra deposits appearing as spikes in plots of HU against depth down the core. In the next phase of our project we will sample the ostensible cryptotephra deposits marked by the CT scans and HU spikes, together with adjacent ‘blank’ sediments for comparison, and evaluate the authenticity of the imaging to accurately delineate cryptotephra deposits. We compared the results of CT scanning with descriptions and photographs of the cut cores, ranking potential tephra deposits in the cores in a three-part classification system as follows: “macro” – readily visible and distinct layer in cut core, >2 mm in thickness, and evident in scanning results; “micro” – indistinct in cut core and/or <2 mm in thickness, evident as a layer in scanning results; and “crypto” (sensu stricto) – not visible in cut core, only detected in scanning results. Our preliminary analysis of these data revealed as many as ~100 potential cryptotephra deposits in the sediment cores, more than doubling the number of tephra-fall events represented in the region (since c. 22,000 years ago). We conclude that the use of X-ray CT scanning, image analyses, and HU plotting can be used firstly to readily detect possible cryptotephra deposits, and secondly to inform a more targeted approach to core sampling of potential cryptotephra deposits to enable chemical analysis of their glass and crystal constituents to be undertaken, ultimately aiding their correlation and the construction of more detailed histories of ashfall events. Together with spatial information, these enhanced frequency records enable probabilistic modelling for future events to be evaluated more realistically, thereby supporting the development of appropriate management strategies for ashfall hazards and potential impacts for specific regions.

O 3.5 in Oral session 3: 25.06.2018, 17:30-17:45

Fingerprinting rhyolitic tephra layers in New Zealand with µ-XRF core scanning: Towards a faster and non-destructive method for tephrochronology 1 1 2 LEONIE PETI , PAUL AUGUSTINUS , PATRICIA GADD 1 School of Environment, University of Auckland, New Zealand 2 Australian Nuclear and Science Technology Organisation, Sydney, Australia Contact: [email protected]

Quaternary paleoenvironmental and hazard studies rely on robust chronologies for the event records being dated. In volcanically-active regions, such as North Island New Zealand, tephrochronology is of considerable importance in this regard and a powerful tool for establishing age control, especially in lake sediment and peat sequences. In New Zealand, the Auckland Volcanic Field (AVF) and the Taupo Volcanic Zone (TVZ) provide a wealth of basaltic, andesitic and rhyolite tephra layers.

Laminated lake sediment records from maars in Auckland City provide outstanding records of both proximal (AVF) and distal tephra (TVZ). The tephra encountered in the AVF maar lakes differ geochemically between source volcanic centre and often even between each eruption from the same centre. The very small catchment of each maar (essentially constrained to its crater rim) and large water depth compared to its diameter result in largely undisturbed laminated sediment records with outstanding tephra preservation.

Due to the near instantaneous deposition of tephra over sometimes large areas, these layers serve as isochrons for correlation between maar lake sediment sequences and, if dated, for age control. Traditionally, tephra deposits are identified geochemically via so-called ‘geochemical fingerprinting’ using time-consuming and destructive electron microprobe analyses (EMPA; for major element oxides) and laser ablation inductively coupled plasma 43 mass spectrometry (LA-ICP-MS; for minor and trace elements). µ-XRF core scanning, on the other hand, provides high-resolution counts of a wide range of elements (Aluminium and heavier) using rapid and non-destructive scanning of sediment cores, as is done routinely for lake sediment-based paleoenvironmental studies. During the same µ-XRF scans elemental data useful for tephra identification and characterisation can also be obtained without any further sample preparation.

µ-XRF scanning of a range of well-characterized tephra layers encountered in AVF maar lake sediment sequences demonstrated that the µ-XRF elemental data can distinguish between 13 rhyolitic tephra layers from six Auckland maar paleolakes, despite limitations of the µ-XRF scanning approach: µ-XRF core scanning cannot measure elements lighter than Al such as Na and Mg which are used widely in the tephrochronology community for fingerprinting tephra deposits. However, µ-XRF core scanners can detect major, minor and trace elements depending on scanning settings and abundance of each element and result in production of a range of elements. Multivariate statistics are used to decrease the dimensionality of the resulting dataset of high dimensionality, and most importantly, to differentiate between and identify tephra layers based on the µ-XRF elemental counts. Principal component analysis and linear discriminant analyses highlight similarities and differences between tephra layers as well as associations between respective elements and the tephra layers in which they are most abundant.

To be able to use this powerful approach as a rapid and non-destructive method for fingerprinting tephra layers in sediment cores from northern New Zealand, scanning of a larger range of tephra layers of rhyolitic as well as tephra of basaltic and andesitic geochemistry is necessary. As in the case of rhyolite tephra, they need to be characterised by their µ-XRF elemental properties under various scanning settings (Molybdenum and Chromium X-Ray tubes, exposure time, voltage and current).

Repeated scans of rhyolitic tephra layers of known source, age and geochemistry from the Orakei maar paleolake has been used to establish statistically-reliable standard normalised µ-XRF elemental counts and elemental ratios for selected rhyolitic tephra layers from TVZ New Zealand. In this way, we have established the foundation for a comprehensive database of µ-XRF elemental counts of rhyolitic tephra layers in New Zealand by recording all scanning parameters (Itrax laboratory identification, detector specifications, tube type, exposure time, voltage and current used).

44

O 3.6 in Oral session 3: 25.06.2018, 17:45-18:00

Authigenic calcite formation in tephra: A mechanism for enhanced carbon drawdown at the end of the PETM 1 1 1 2 JACK LONGMAN , MARTIN PALMER , THOMAS GERNON , HAYLEY MANNERS 1 School of Ocean and Earth Sciences, University of Southampton, United Kingdom 2 School of Geography, Earth and Environmental Sciences, University of Plymouth, United Kingdom Contact: [email protected]

One of the most important, and yet poorly-constrained features of the Earth’s system, is the carbon cycle and its feedbacks. In particular, our understanding of sinks and cycles in the marine realm, and during periods of enhanced CO2 emission, mean predictions of the impact of ongoing anthropogenic climate change upon the cycle are uncertain. One approach to understanding the behaviour of the carbon cycle during periods of enhanced carbon emission is to investigate events in Earth’s history in which similar conditions prevailed. The Paleocene-Eocene Thermal Maximum (PETM) was a period of rapid global warming (roughly 4 – 5°C increase for 170,000 years) which occurred 55.8 million years before present (Ma), and has been suggested to be one such event. The PETM appears to have been caused by a period of intense volcanism, with evidence for Large Igneous Province emplacement associated with the formation of the North Atlantic Igneous Province (NAIP) at the end of the Paleocene appearing to confirm a volcanic control. Associated with the emplacement of igneous material was the eruption of large quantities of ash during explosive volcanism. Evidence for wide-ranging ash deposition across much of north-western Europe (Fig. 1)is observed within PETM-age sediments as far afield as the Goban spur southwest of Britain, northern Germany, Denmark, and the North Sea basin.

The nature of events at the end of the PETM has been subject to much discussion, as understanding the drivers behind the rapid return to a ‘normal’ global carbon cycle may be valuable when considering the current and future Earth system. It is apparent that the drawdown of atmospheric CO2 at the end of the PETM is more rapid than can be ascribed to silicate weathering alone. Hence, the rapid nature of post-PETM recovery has been ascribed to a variety of mechanisms, including elevated levels of organic matter burial, via an enhanced biological pump and heightened nutrient supply. Other theories suggest enhanced carbonate formation as a result of increased weathering, and possibly associated with a deeper carbonate compensation depth (CCD), but no consensus has yet been reached.

New data presented here suggests that the deposition of explosive eruption products (tephra), under sub-oxic diagenetic conditions, may act to enhance carbon sequestration, through the formation of authigenic carbonate. Geochemical data is presented from a selection of mudstone-hosted tephras deposited during, or just after the PETM, from two Deep Sea Drilling Project (DSDP) holes; 553A and 555. These data are used to investigate the possibility that the major volcanic eruptions that appear to have caused the PETM, may also have played an important role terminating the high CO2 interval.

45

Oral session 4

O 4.1 in Oral session 4: 27.06.2018, 08:30-08:45

Challenges in dating of Nisyros tephra 1 1 2 3 GONCA GENCALIOGLU KUSCU , GÖKSU USLULAR , MARTIN DANIŠÍK , ANTHONY A.P. KOPPERS , 3 DAN MIGGINS 1 Department of Geological Engineering, Mugla Sitki Kocman University, Turkey 2 GeoHistory Facility, John de Laeter Centre, TIGeR, School of Earth and Planetary Sciences, Curtin University, Perth, WA 6845, Australia 3 College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA Contact: [email protected]

Kos-Nisyros-Yali volcanic system in the South Aegean Volcanic Arc is the site for one of the most powerful eruptions in the Quaternary. Despite the well constrained 40Ar/39Ar age (161.3 ± 1.1 ka on sanidine) of Kos Plateau Tuff eruption by Smith et al. (1996), the age of the Nisyros tephra units is still problematic. The K-Ar method was the most widely used for the pre-caldera tephra units, but did not provide accurate ages. Other geochronological methods (14C, O isotopes, fission track) employed for the caldera-forming tephra, and use of distal marine tephra for stratigraphy and correlation also produced conflicting and wide range of ages.

According to the detailed volcanological descriptions by Volentik et al. (2005), the Nisyros pre-caldera tephra from oldest to youngest are Lakkí A-B (andesitic), Melisserí-Stavros (andesitic), Pahia Ammos or Kyra (basaltic andesitic to dacitic), and Xolante (basaltic andesitic); followed by the present caldera forming/post-caldera Lower Pumice (LP, rhyolitic) and Upper Pumice (UP, rhyodacitic).

Until recently published geochronological data were ranging from 24 ± 0.56 (Rehren, 1988) to 47 ± 6 ka (Margari et al., 2007) (both by 14C) for the LP; and from >44 ka (14C on charcoal, Limburg and Varekamp (1991) to 110 ± 40 ka (fission track on volcanic glass, Barberi et al. 1988) for the UP. The range for pre-caldera lower andesitic lavas and pyroclastics (Lakki A- B) was even larger, from 100±100 to 800 ± 700 ka (K-Ar whole rock, Matsuda et al., 1999), while the Pahia Ammos/Kyra tephra was dated as 24-39 ± 26 ka (K-Ar on matrix, Rehren, 1988). Most recent and direct geochronological estimates by Guillong et al. (2014) for the LP and UP by LA-ICP-MS on zircon reveal that the youngest age for the UP unit should be <70 ± 24 ka, and LP should be younger than 124 ± 35 ka. These ages are obviously in conflict with the previously reported ages for the Nisyros pre-caldera andesitic tephra.

Therefore, we attempted to date the mid-distal pumice lapilli identified at several locations on neighbouring Datça peninsula (SW Anatolia), previously correlated to Nisyros Kyra based on field observations (Keller et al., 1990). Andesitic pumice lapilli on Datça are characterized and mainly correlated to Kyra (and to some extend with Lakki and Melisseri) based on field, petrographical, and geochemical evidence by Gençalioğlu-Kuşcu and Uslular (2018). For the sake of a better age constraint we applied the apatite (U-Th)/He, and plagioclase and hornblende 40Ar/39Ar dating methods. (U-Th)/He eruption ages of apatite for multi-crystal aliquots (10 crystals) are in the range of 128-144 ka. Also we tried and tested this age with pumice lapilli from other locations in Datça using 40Ar/39Ar on plagioclase and hornblende. Calculated plateau ages on plagioclase are 133.5 ± 26.3 and 123 ± 24.6 ka, respectively for lapilli from two different locations. Based on our combined (U-Th)/He and 40Ar/39Ar ages, it is clear that mid-distal Nisyros pre-caldera tephra on Datça is not 24-39 ka old, as previously assumed. The age of the pre-caldera tephra being older than 24-39 is in agreement with the ages provided by Guillong et al., (2014) for LP and UP. Our results also imply that the volcanism in the Kos-Nisyros-Yali volcanic system was almost continuous, and work should be extended to get a better geochronological framework of the Nisyros volcano. 46

References Barberi, F., Navarro, JM, Rosi, M., Santacroce, R., Sbrana, A., 1998. Explosive interaction of magma with ground water: insights from xenoliths and geothermal drillings. Rend. Soc. Italian. Mineral. Petr., 43, 901-926. Gençalioğlu-Kuşcu, G., Uslular, G., 2018. Geochemical characterization of mid-distal Nisyros tephra on Datça peninsula (southwestern Anatolia), J. Volcanol. Geotherm. Res., 354, 13-28. Guillong, M., von Quadt, A., Sakata, S., Peytcheva, I., Bachmann, O., 2014. LA-ICP-MS Pb–U dating of young zircons from the Kos–Nisyros volcanic centre, SE Aegean arc. J. Anal. At. Spectrom. 29, 963–970. Keller, J., Rehren, T.H., Stadlbauer, E., 1990. Explosive volcanism in the Hellenic arc. In: Hardy, D.A., Keller, J., Galanopoulos, V.P., Fleming, N.C., Druitt, T.H. (Eds.), Thera and the Aegean World, III, Proceedings of the Third International Congress, Santorini, Greece, 3–9 September 1989. vol. 487. The Thera Foundation, pp. 13–26. Limburg, E.M., Varekamp, J.C., 1991. Young pumice deposits on Nisyros, Greece. Bull. Volcanol. 54, 68–77. Margari, V., Pyle, D.M., Bryant, C., Gibbard, P.L., 2007. Mediterranean tephra stratigraphy revisited: results from a long terrestrial sequence on Lesvos Island, Greece.J. Volcanol. Geotherm. Res. 163, 34–54. Matsuda, J., Senoh, K., Maruoka, T., Sato, H., Mitropoulos, P., 1999. K-Ar ages of the Aegean volcanic rocks and their implications for the arc-trench system, Geochem. J. , 33, 369-377. Rehren, T.H., 1988. Geochemie und Petrologie von Nisyros (östliche Agais). Ph.D. Thesis. University of Freiburg, Germany. Smith, P.E., York, D., Chen, Y.,Evansen, N.M., 1996. Single crystal 40Ar–39Ar dating of Late Quaternary paroxysm on Kos, Greece: concordance of terrestrial and marine ages. Geophys. Res. Lett. 23, 3047–3050. Volentik, A., Vanderkluysen, L., Principe, C., Hunziker, J.C., 2005. Stratigraphy of Nisyros Volcano, (Greece). In: Hunziker, J.C., Marini, L. (Eds.), The Geology, Geochemistry and Evolution of Nisyros Volcano (Greece). Implications for the Volcanic Hazards, Mémoires de Géologie: Lausanne vol. 44, pp. 26–66. Research was granted by Scientific Research Project Office of Muğla Sıtkı Koçman University (BAP Projects 15/070 and 15/077).

O 4.2 in Oral session 4: 27.06.2018, 08:45-09:00

Chances and challenges in dating tephra marker horizons by luminescence dating techniques 1 2 3 4 5 JANINA BÖSKEN , NICOLE KLASEN , IGOR OBREHT , ULRICH HAMBACH , DAN VERES , CHRISTIAN 6 7 2 2 8 ZEEDEN , SLOBODAN MARKOVIĆ , CHRISTOPH BUROW , DOMINIK BRILL , STEPHAN PÖTTER , 8 FRANK LEHMKUHL 1 Department of Physical Geography and Geoecology, Geographical Institute, RWTH Aachen University, Germany 2 Institute of Geography, University of Cologne, Germany 3 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Germany 4 BayCEER & Chair of Geomorphology, University of Bayreuth, Germany 5 Institute of Speleology, Romanian Academy, Cluj-Napoca, Romania 6 IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, France 7 Laboratory for Palaeoecological Reconstruction, University of Novi Sad, Serbia 8 Department of Physical Geography and Geoecology, Geographical Institute, RWTH Aachen University Contact: [email protected]

Tephra layers are excellent time markers in paleoenvironmental archives. These can be used for correlation between different archives and give stratigraphic control independent of the applied dating techniques. Terrestrial archives such as loess-paleosol sequences are often dated by luminescence or radiocarbon dating, depending on the material available. 47

While radiocarbon dating is only applicable for younger timescales, luminescence ages overcome this problem to a certain extent. However, they are accompanied by wider errors that are often too imprecise for some geochronological and paleoenvironmental questions. It is thus often useful to apply different dating techniques to cross-validate their results. Since tephra layers can sometimes be dated directly and very precisely (e.g. by 40Ar/39Ar dating), they can be used as a reference to validate the results of other chronological methods such as luminescence dating.

Here, we present the Stalać and the Urluia loess-paleosol sequences and their geochronological investigations. The Stalać section in southern Serbia contains the “L2- Tephra” and a cryptotephra related to the Campanian Ignimbrite/Y-5 tephra (cf. Bösken et al., 2017; Obreht et al., 2016). The L2-Tephra is preserved in several loess-paleosol sequences in southeastern Europe (cf. Laag et al., INTAV conference abstract). Its labelling is related to its deposition within the L2 loess package, usually correlated to marine isotope stage 6 (e.g. Marković et al., 2015). Furthermore, also the Urluia section contains the Campanian Ignimbrite/Y-5 tephra (Obreht et al., 2017) that is widely distributed in southeastern Europe (e.g. Fitzsimmons et al., 2013) and dated to 39.85 ± 0.14 ka (Giaccio et al., 2017). This contribution identifies challenges in dating tephra layers by luminescence dating techniques and highlights its possibilities and prospects.

O 4.3 in Oral session 4: 27.06.2018, 09:00-09:15

Direct and indirect luminescence dating of tephra: methodological considerations 1 CHRISTOPH SCHMIDT 1 Chair of Geomorphology, University of Bayreuth, Germany Contact: [email protected]

Absolute tephrochronology relies on the availability of numerical ages for the volcanic activity responsible for the tephra fallout. In circumstances where common radiometric dating techniques such as the 40Ar/39Ar method fail (e.g., due to the young age and insufficient amounts of radiogenic He), luminescence may help to chronologically constrain volcanic eruptions and associated tephra deposits.

Direct luminescence dating of tephra generally refers to the events of cooling of juvenile volcanic rocks (e.g., volcanic glass) or to the events of light exposure and exertion of pressure to minerals contained in shattered bedrock/country rock. Volcanic rocks usually show a loss of luminescence signal over time (so-called anomalous fading) that results in (severe) age underestimation. Therefore, in the case of proximal tephra generated by phreatomagmatic explosions it appears more promising to use sand-sized quartz or feldspar crystals derived from bedrock clasts as target minerals for luminescence dating since these are free or less affected by anomalous fading. It has been questioned whether pressure and illumination during the phreatomagmatic eruption are sufficient to completely reset the inherited (geological) luminescence signal of these clasts, but recent case studies indicate that this approach can produce reliable ages in certain settings.

In case a clear assignment of distal tephra deposits and the center of eruption exists, numeric ages for the tephra can be obtained by dating heated bedrock or xenoliths associated with the volcanic phase producing the tephra. The applicability of this approach, however, depends strongly on the type of bedrock in the area of volcanic activity as well as on the dynamism of the eruption.

The present contribution aims to shed light on the potentials, but also the challenges to face, when applying the above-mentioned luminescence methods to obtain tephra ages. These 48 methodological considerations will be illustrated by examples of successful and failed attempts of dating tephra from various geological settings.

O 4.4 in Oral session 4: 27.06.2018, 09:15-09:30

LA-ICP-MS mapping of volcanic glass: A promising technique for measuring trace element abundances in small tephra particles 1 2 3 JEFFREY OALMANN , MARCUS PHUA , CAROLINE BOUVET DE MAISONNEUVE 1 Earth Observatory of Singapore, Nanyang Technological University, Singapore 2 Asian School of the Environment, Nanyang Technological University, Singapore 3 Earth Observatory of Singapore and Asian School of the Environment, Nanyang Technological University, Singapore Contact: [email protected]

Many sedimentary environments such as lacustrine and marine settings accumulate tephra for thousands to millions of years. Therefore, these geologically stable areas can provide a longer and more complete volcanic record than dynamic and chaotic volcanic source terranes. Furthermore, if glass shards can be compositionally linked to volcanic sources with known ages, tephra layers can be used to determine the absolute ages of sedimentary sequences where biostratigraphic or radiometric ages are unavailable or ambiguous. In many cases, trace element compositions of volcanic glass are better than major element compositions at distinguishing different sources or different eruptions of the same volcano. However, the small size of glass shards, presence of microlites, and other inhomogeneities make obtaining precise and accurate trace element data challenging.

Here we present the results of trace element mapping of individual glass shards by LA-ICP- MS. Multiple line scans were used to ablate areas that include one or more glass shards using a 10 x 10 µm square laser spot, 10 Hz repetition rate, and 5-7 µm/s scan speed. The number of measured isotopes and dwell times were minimized in order to maximize the amount of data collected across the areas. The Iolite LA-ICP-MS data reduction software (Paton et al. 2011 JAAS) was used to construct quantitative CellSpace maps (Paul et al. 2012 JAAS), using Si as the internal standard element (as recommended by Pearce, 2014 JQS). The Monocle plug-in for Iolite (Petrus et al. 2017 Chem Geol) was then used to select and average data from homogenous areas.

The ablation parameters used in this method result in ablation depths of ≤1 µm, making it an ideal technique for analyzing small glass shards with high surface area to thickness ratios. Furthermore, microlites, inclusions, or other impurities can be recognized in the maps and excluded from the composition calculations. Preliminary trials indicate that measurements made by mapping are at least as precise as measurements made by traditional LA-ICP-MS analyses using a 10 µm ablation spot size. Repeated analyses of well classified reference materials (e.g. MPI-DING glasses) have 2SE values of less than 10% and are within 10% of the accepted values for most trace elements without further correction. The resulting accuracy indicates that laser-induced inter-element fractionation is minimized. Therefore, only minimal correction of unknowns using secondary reference materials is required. Trace element compositions obtained for glass shards separated from a tephra layer within a marine sediment core collected in the northeast Indian Ocean are within the range of compositions reported for the Youngest Toba Tuff (Westgate et al. 2013 JQS), verifying the validity of this technique.

O 4.5 in Oral session 4: 27.06.2018, 09:30-09:45 49

A Bayesian age-depth modelling of a full Pliocene-Quaternary tephrochronological framework for the Northwest Pacific Deep Sea cores 1 2 3 4 EGOR ZELENIN , VERA PONOMAREVA , NATALIA BUBENSHCHIKOVA , MAXIM PORTNYAGIN , 5 ALEXANDER DERKACHEV 1 Geological Institute, Moscow, Russia 2 Institute of Volcanology and Seismology, Petropavlovsk-Kamchatsky, Russia 3 P.P.Shirshov Institute of Oceanology, Moscow, Russia 4 GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; V.I.Vernadsky Institute of Geochemistry and Analytical Chemistry, Moscow, Russia 5 V.I. Il'ichev Pacific Oceanological Institute, Vladivostok, Russia Contact: [email protected]

Geochemically fingerprinted widespread tephra layers are excellent marker horizons that can serve as isochrons over vast areas. Deep sea sediments in the areas close to the volcanoes provide a continuous tephra record over millions of years. This study considers deep sea cores taken at sites 882 and 884 during the Ocean Drilling Program (ODP) Leg 145 of the R/V JOIDES Resolution in 1992 (Rea et al., 1993), and a giant piston core MD01-2416 obtained during the WEPAMA cruise of the R/V Marion Dufresne in 2001 in the frame of the IMAGES program (Holbourn et al., 2002), all located on the Detroit Seamount in the NW Pacific.

Geochemical correlations of tephra layers among the three cores have permitted the construction of the summary tephra sequence that includes 109 individual layers deposited over the last 6 My. This permits us to combine individual age-depth models for each site into the integral and consistent age model. Initial biostratigraphical age models for sites 881 and 884 as well as the downcore magnetic inclination data were obtained by the ODP Leg 145 team. After that, some astrochronological age models were published, however, none of the cores were included in 18O benthic stack LR04 (Lisiecki and Raymo, 2005).

The main high-resolution age models for these sites are:

- Site ODP 882 - XRF correlations to Antarctic EPICA Dome C age model (EDC3) for the last 800 ky (Jaccard et al., 2010); astronomical tuning of gamma-ray attenuation porous evaluation variations for the last 4 My (Tiedemann and Haug, 1995); magnetic reversals correlations of the bottom 100m of the core.

- Site MD01-2416 - 14C dates for the interval between 10 and 20 ka BP (Sarnthein et al., 2015); 18O correlations to the marine isotope stages for the last 1,3 My (Gebhardt et al., 2008).

- Site ODP 884 -14C dates and 18O correlations to the marine isotope stages for the last 250 ky (VanLaningham et al., 2009); a continuous record of distinct geomagnetic reversals, which were correlated to geomagnetic polarity time scale of Cande and Kent (1992).

Accuracy of these models is not uniform. As shown by Lisiecki and Raymo (2005), 18O records of deep sea sediments converge within 4 ky in the late Quaternary to 30 kyrs in Miocene, and for the EDC3 the age accuracy comprises 3 ky (Dreyfus et al., 2007, Jouzel et al., 2007). Therefore, we need to estimate ages of the events, taking into account all the individual high-resolution age models. As the known data include some prior age estimations and empirical observations of tephra correlations, the most suitable approach is a Bayesian statistics. We have constructed an age model, where each date was treated as a boundary of uniform deposition sequence with known depth, age and its uncertainty, while tephra layers linked these sequences. The model was processed in OxCal 4.3 software (Bronk Ramsey, 2009), which is a powerful tool for Bayesian age modelling suitable not only for 14C ages. As a result, we have obtained an integrated and consistent age model, incorporating all the tephras found in the cores with accuracy estimations varying from 500 yrs after LGM 50 to some 25 ky in early Pliocene. The real accuracy may be slightly lower, as we infer uniform deposition rate between the tie points.

This study provides age estimates for the tephrochronological framework of the entire Pleistocene-Quaternary of NW Pacific. Tephras found in these cores some 700 km off the coast correspond to VEI 5 or larger eruptions, so they could serve as isochrons in the marine, terrestrial and ice records of the region, providing additional age data to local chronological studies.

References Bronk Ramsey, C. (2009). Bayesian analysis of radiocarbon dates. Radiocarbon, 51(1), 337-360. Cande, S. C., & Kent, D. V. (1992). A new geomagnetic polarity time scale for the Late Cretaceous and Cenozoic. Journal of Geophysical Research: Solid Earth, 97(B10), 13917-13951. Dreyfus, G. B., Parrenin, F., Lemieux-Dudon, B., et al. (2007). Anomalous flow below 2700 m in the EPICA Dome C ice core detected using d 18 O of atmospheric oxygen measurements. Climate of the Past Discussions, 3(1), 63-93. Gebhardt, H., Sarnthein, M., Grootes, P. M., et al. (2008). Paleonutrient and productivity records from the subarctic North Pacific for Pleistocene glacial terminations I to V. Paleoceanography, 23(4). Holbourn, A., Kiefer, T., Pflaumann, U., Rothe, S. 2002. WEPAMA Cruise MD 122/ IMAGES VII, Rapp. Campagnes Mer OCE/ 2002/01, Inst. Polaire Fr. Paul Emile Victor (IPEV), Plouzane´, France. Jaccard, S. L., Galbraith, E. D., Sigman, D. M., & Haug, G. H. (2010). A pervasive link between Antarctic ice core and subarctic Pacific sediment records over the past 800 kyrs. Quaternary Science Reviews, 29(1-2), 206-212. Jouzel, J., Masson-Delmotte, V., Cattani, O., et al. (2007). Orbital and millennial Antarctic climate variability over the past 800,000 years. Science, 317(5839), 793-796. Lisiecki, L. E., & Raymo, M. E. (2005). A PliocenePleistocene stack of 57 globally distributed benthic δ18O records. Paleoceanography, 20(1). Rea, D.K., Basov, LA., Janecek, T.R., Palmer-Julson, A., et al., 1993. Proceedings of the Ocean Drilling Program, Initial Reports, Vol. 145. Sarnthein, M., Balmer, S., Grootes, P. M., & Mudelsee, M. (2015). Planktic and benthic 14 C reservoir ages for three ocean basins, calibrated by a suite of 14 C plateaus in the glacial-to-deglacial Suigetsu atmospheric 14 C record. Radiocarbon, 57(1), 129-151. Tiedemann, R., and Haug, G.H. (1995). Astronomical calibration of cycle stratigraphy for Site 882 in the northwest Pacific. In Rea, D.K., Basov, I.A., Scholl, D.W., and Allan, J.F. (Eds.), Proc. ODP, Sci. Results, 145: College Station, TX (Ocean Drilling Program), 283–292. VanLaningham, S., Pisias, N. G., Duncan, R. A., & Clift, P. D. (2009). Glacial–interglacial sediment transport to the Meiji Drift, northwest Pacific Ocean: Evidence for timing of Beringian outwashing. Earth and Planetary Science Letters, 277(1), 64-72.

51

O 4.6 in Oral session 4: 27.06.2018, 09:45-10:00

Modern cryptotephra and high-resolution Bayesian age modelling of peat bog profiles: a case study using six sites from Alberta, Canada 1 1 2 1 3 LAUREN DAVIES , DUANE FROESE , PETER APPLEBY , BRITTA JENSEN , GABRIEL MAGNAN , 4 4 4 3 GILLIAN MULLAN-BOUDREAU , TOMMY NOERNBERG , WILLIAM SHOTYK , SIMON VAN BELLEN , 5 CLAUDIO ZACCONE 1 Department of Earth and Atmospheric Sciences, University of Alberta, Canada 2 Department of Mathematical Sciences, University of Liverpool, United Kingdom 3 Geotop, Université du Québec à Montréal, Canada 4 Department of Renewable Resources, University of Alberta, Canada 5 Department of the Sciences of Agriculture, Food and Environment, University of Foggia, Italy Contact: [email protected]

Recent peat profiles are frequently studied for high-resolution studies of contaminants and understanding of recent environmental change, but the most common dating techniques applied (e.g. 14C, 210Pb, cryptotephra) are rarely combined or used for testing and inter- comparison. Here, we integrate three chronometers to produce a single age model to comprehensively investigate variations in these dating methods and the individual site histories since AD 1850. The presence of glass from Novarupta-Katmai 1912 is used as an independent verification for 14C and 210Pb dates. Additionally, environmental data (e.g. plant macrofossils, humification, ash content and dry density) provide important constraints for the model by highlighting periods with significant changes in accumulation rate (e.g. fire events, permafrost development or prolonged surficial drying). OxCal’s P_Sequence function is used to model dates produced from the six peat bogs in central and northern Alberta. These methods can successfully be combined in a Bayesian model and used to produce a single age model that more accurately accounts for the uncertainties inherent in each method. Sub- cm resolution output shows there are consistent differences in how the 14C and 210Pb signals are preserved in peat profiles, with 14C commonly showing a slight bias toward older ages at the same depth relative to 210Pb data. Understanding these differences and combining data from multiple methods results in a stronger chronology at each site investigated here despite observed differences in ecological setting, accumulation rates, fire events/frequency and permafrost development.

Oral session 5

O 5.1 in Oral session 5: 27.06.2018, 16:30-16:45

Paleoclimate and paleoenvironment in the Ciomadul volcanic area after and before the last eruption 1 2 3 4 5 ENIKŐ MAGYARI , DANIEL VERES , KRISZTINA BUCZKÓ , MÓNIKA TÓTH , ILDIKÓ VINCZE , WALTER 6 7 FINSINGER , DÁVID KARÁTSON 1 Department of Environmental and Landscape Geography, Research group of Paleontology, Eötvös Loránd University, Budapest, Hungary 2 Romanian Academy, Institute of Speleology, Cluj-Napoca, Romania 3 Hungarian Natural History Museum, MTA Centre for Ecological Research, Budapest, Hungary 4 MTA Centre for Ecological Research, Balaton Limnological Institute, Hungary 5 Department of Geology, Eötvös Loránd University, Budapest, Hungary 6 Palaeoecology, Institut des Sciences de l’Evolution, Montpellier, France 7 Department of Physical Geography, Eötvös Loránd University, Budapest, Hungary Contact: emagyari@caesar.elte.hu

At the time of the last eruption of the St Ana crater (~29,600 cal yr BP) macrocharcoal studies testify extensive arolla pine (Pinus cembra) forest cover in the Ciomadul volcanic 52 area, in line with the paleoclimate model based inferences for boreal climate during the terminal part of Greenland Isotope Stage-3 (GS-3). The accumulation of lake sediments after the last eruption allows us to reconstruct how vegetation cover of the crater slope has changed, what weathering and soil forming processes influenced the inwash of nutrients into the lake, and how it influenced the development of the lakeshore and in-lake vegetation and fauna. Using multi-proxy paleoecological methods (pollen, plant macrofossil, macro- and microcharcoal, chironomid, diatom), grain size, organic content, mineral magnetic and chemical analyses of the sediment, the last glacial maximum (LGM), Late Glacial and Holocene paeloenvironmental changes have been reconstructed during the last decade following repeated coring attempts to reach the bottom of the lake sediment.

Our results suggest the persistence of boreal forest steppe vegetation (with Pinus, Betula, Salix, Populus and Picea) in the foreland and low mountain zone of the East Carpathians and Juniperus scrubland at higher elevation during the LGM. The crater slope was treeless at this time, and sparse steppe tundra vegetation prevailed. We demonstrated attenuated response of the regional vegetation to maximum global cooling, and between ~22,870 and 19,150 cal yr BP we found increased regional biomass burning, but no signs of local fire events supporting the absence of local woody biomass. Directly after the LGM, from ~19,150 cal yr BP, xerophytic steppes expanded in the region, and we also noticed regional increase in boreal woodland cover with Pinus sylvestris, Pinus cembra, Larix decidua and Betula species from 16,300 cal yr BP. Plant macrofossils indicated local (950 m a.s.l.) establishment of Betula nana and Betula pubescens at 15,150 cal yr BP, Pinus sylvestris at 14,700 cal yr BP and Larix decidua at 12,870 cal yr BP. Trees were however likely established earlier on the crater slope, as macrocharcoal concentrations indicative of local burning increased since 16,500 cal yr BP, in agreement with the pollen inferred increase in regional woodland cover.

Diatom-inferred lake water chemistry showed remarkable change between 15,000 and 13,800 cal yr BP. While the LGM was characterized by near-neutral, slightly alkaline pH (7- 7.4), a shift to acidic environment (pH= 6.1-6.6) was detected during the Late Glacial Onset that together with the terrestrial vegetation change could suggest very rapid podzol soil formation on the crater slope and acidifying conditions due to conifer forest cover. The shallow, about 5-10 m deep lake’s water depth decreased abruptly during the Late Glacial, and reached its lowest level during the Allerød interstadial. The YD cooling can be well detected in the sediment, the regional vegetation response was the expansion of xerophytic steppes, and parallel with this change the water-depth increased (inferred by the green algae flora and diatoms). This antagonistic behavior of the regional forest cover and water depth is a characteristic feature of the rain fed sedimentary basins in the Carpathian Basin and suggests that either the seasonal distribution of the precipitation has changed or evaporation decreased due to lower vegetation season temperatures.

Chironomid-inferred mean July temperature reconstruction covers the period between 17,000 and 9000 cal yr BP and shows the strongest July temperature increase at 16,200 cal yr BP, from 8 to 13 oC. This 5 oC increase in July temperatures is the largest amplitude change in the studied period and supports pollen, plant macorofossil and diatom based inference for an earlier post-LGM warming compared to NW Europe. These inferences are also corroborated by the paleclimate proxies of the Black Sea sediment records.

53

O 5.2 in Oral session 5: 27.06.2018, 16:45-17:00

Eruption ages and geochemical fingerprints of the distal tephras from the Late Pleistocene Ciomadul volcano, East Carpathians 1 2 3 3 4 SZABOLCS HARANGI , KATA MOLNÁR , BALÁZS KISS , RÉKA LUKÁCS , ISTVÁN DUNKL , AXEL K. 5 6 7 8 9 SCHMITT , IOAN SEGHEDI , ÁGNES NOVOTHNY , MIHÁLY MOLNÁR , REBEKA OROSS , 10 11 THEODOROS NTAFLOS , PAUL R.D. MASON 1 MTA-ELTE Volcanology Research Group and Department of Petrology and Geochemistry, Eötvös University 2 Department of Petrology and Geochemistry, Eötvös University, Budapest and ATOMKI, Debrecen, Hungary 3 MTA-ELTE Volcanology Research Group, Budapest, Hungary 4 Geoscience Centre, Georg-August University, Göttingen, Germany 5 Institute of Earth Sciences, Ruprecht-Karls University, Heidelberg, Germany 6 Institute of Geodynamics, Romanian Academy, Bucharest, Romania 7 Department of Physical Geography, Eötvös University, Budapest, Hungary 8 Hertelendi Laboratory of Environmental Studies, ATOMKI, Debrecen, Hungary 9 Department of Petrology and Geochemistry, Eötvös University, Budapest, Hungary 10 Department of Lithospheric Research, University of Vienna, Austria 11 Department of Earth Sciences, Utrecht University, The Netherlands Contact: [email protected]

Distal volcanic deposits could provide additional constraints on explosive volcanic events even when no proximal deposits have been preserved. Late Pleistocene tephras are widespread in the Mediterranean and surrounding areas and they are used as important isochronous markers in the stratigraphic sections (Tomlinson et al., 2012; 2015). Most of them are the products of large explosive eruptions in Italy, Turkey and Greece. New age data (Harangi et al., 2015) suggested, however, that explosive volcanic eruptions occurred at Ciomadul, East Carpathians, Romania (Szakács et al., 2015) between 57 ka and 32 ka and thus it adds a further potential source for tephras in the eastern Mediterranean. In the last years, tephra occurrences from the Black sea sediments (Harangi et al., 2015), from the Roxolany loess section (Wulf et al., 2016) and from a Middle Palaeolithic cave sequence (Veres et al., 2018) were deduced to have been derived from Ciomadul volcano. However, some concerns have still remained, mostly because of the uncertainties in the eruption ages and the compositional features. Here, we present new age data for the distal tephras of Ciomadul and characterize the geochemical fingerprint of the volcanic products using both mineral chemistry, glass and bulk rock compositions.

Eruption age of distal tephras found in the vicinity (within 25 km distance) of the Ciomadul lava dome complex was determined by (U-Th)/He dating combined with U-Th geochronology on zircons separated directly from the eruptive material, OSL (Optically Stimulated Luminescence) and post-IR IRSL (infrared stimulated luminescence) dating of the sediments embedding the tephras and radiocarbon dating of a palaeosoil underlain a tephra bed. In particular, we provided great effort to constrain better the age of the tephra at Târgu Secuiesc/Kézdivásárhely, a 20 cm thick pumiceous lapilli stone bed 22 km from the Mohoş and Sf. Ana craters. The age of this volcanic deposit was controversial (Harangi et al., 2015; Karátson et al., 2016) and therefore, we analyzed additional zircon grains for (U-Th)/He dates and combined them with U-Th dates of the outer 4 micron margin of zircon crystals. These latter dates, as the youngest crystallization age of zircons, provide the upper limit of the eruption age. Furthermore, we conducted OSL and post-IR IRSL dating of the host sediment. Our new results show that the large explosive volcanic eruption at Ciomadul produced this pumice tephra and deposited >20 km from the volcano could have occurred between 31 and 33 ka with uncertainties of ± 2 ka.

North of Ciomadul, another marked tephra bed is found within a minimum 15 meter thick Pleistocene gravelly fluvial sedimentary sequence at Sânmartin/Csíkszentmárton. A coarse ash tephra layer with 30 cm thickness is deposited above a brown palaeosoil bed and it is overlain by a 70 cm thick grey volcanoclastic material. This tephra occurrence was 54 considered to belong to a phreatomagmatic eruption phase occurred at ca. 50 ka based on glass compositional data (Karátson et al., 2016). We performed zircon (U-Th)/He dating combined with U-Th dating on zircons selected from the coarse ash bed and determined the age of the palaeosoil by radiocarbon dating. The individual zircon dates show a large spread; therefore a careful evaluation of the data was necessary. We applied also double dating, what is considered to be the most accurate method by Danišík et al. (2017) and this resulted in 29.7 ± 2.2 ka (U-Th)/He age. On the other hand, 37.5 ± 2.2 ka was obtained from 5 zircon dates after average crystallization age correction. At this stage, it is difficult to constrain better the eruption age of this tephra based on zircon dating, since the youngest rim age is 55 ± 10 ka. We obtained 33600-32100 cal BP for the palaeosoil underlain the tephra bed, where the real age could be a few hundreds or maximum 2000 years younger, considering the reservoir age effect. In summary, based on the new age data the Sânmartin/Csíkszentmárton tephra could have been formed at 30 ka with 3 kyr uncertainty, i.e. belongs to the latest eruption events.

Major element composition of glass shards are widely used to correlate tephra occurrences and identify their sources. The glasses of the Ciomadul tephras are rhyolitic (Vinkler et al, 2007; Karátson et al., 2016), which is distinct compared to the glasses of the Central Mediterranean volcanic products, but show some similarities to the glasses of Late Pleistocene tephras of Pantelleria, Nisyros and Anatolia. However, the trace element signatures of 57-30 ka Ciomadul tephras are distinct (strong enrichment in Ba and Sr, and depletion in heavy rare earth elements; Vinkler et al., 2007 and this study) from all of these volcanic products and therefore, this seems to be the most powerful tool to recognize the Ciomadul source. This correlation can be combined with mineral chemical data, where crystals are found in the far-distal tephra occurrences. The Ciomadul volcanic products have a characteristic mineral assemblage comprising dominantly plagioclase, amphibole and biotite. Within this, amphiboles have a characteristic complex zoned appearance with both hornblende and pargasite composition. However, we emphasize that neither the major element nor the trace element composition of glasses and minerals from the Ciomadul explosive volcanic products can be used to distinguish single eruption events.

Correlation of distal tephras and recognition of their source are often complicated, but can be constrained only by multiple criteria (Lowe, 2011). Here, we provide detailed geochronological and geochemical data what can be used as a fingerprint of the Ciomadul tephras. These data can be effectively used to recognize distal tephras belonging to the 57- 30 ka eruption phase of Ciomadul, but it is much more difficult and at this stage, we think that it is not possible to detect single eruption event.

References Danišík et al. 2017, Quaternary Geochronology, 40: 23-32. Harangi et al. 2015, Journal of Volcanology and Geothermal Research, 301: 66-80 Karátson et al., 2016, Journal of Volcanology and Geothermal Research, 319: 29-51 Lowe 2011, Quaternary Geochronology, 6(2): 107-153. Szakács et al., 2015, Bulletin of Volcanology, 77(2): 1-19. Tomlinson et al., 2012; Journal of Volcanology and Geothermal Research 243, 69-80 Tomlinson et al., 2015, Quaternary Science Reviews 118, 48-66 Veres et al. 2018, Quaternary International, in press Vinkler et al, 2007, Földtani Közlöny, 137(1): 103-128. Wulf et al. 2016, J. Quat Sci., 31, 565-576.

This research was supported by the Hungarian National Research, Development and Innovation Fund (NKFIH) within No. K116528 and No. PD 121048 projects.

O 5.3 in Oral session 5: 27.06.2018, 17:00-17:15 55

Correlation of Miocene tephras in the Carpathian-Pannonian Region and the surrounding areas 1 2 3 4 RÉKA LUKÁCS , SZABOLCS HARANGI , ISTVÁN DUNKL , MARCEL GUILLONG , OLIVIER 4 5 4 6 7 BACHMANN , YANNICK BURET , JAKUB SLIWINSKI , KRISZTINA SEBE , SÁNDOR JÓZSA , ILDIKÓ 1 8 9 SOÓS , ZSOLT BENKÓ , JÖRG PFAENDER 1 MTA-ELTE Volcanology Research Group, Budapest, Hungary 2 MTA-ELTE Volcanology Research Group and Petrology and Geochemistry, Eötvös L. University, Budapest, Hungary 3 Sedimentology & Environmental Geology, Geoscience Center, University of Göttingen, Germany 4 Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zürich, Switzerland 5 Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zürich, Switzerland and Core Research Laboratories, Natural History Museum, London UK 6 University of Pécs, Dept. of Geology and Meteorology, Pécs, Hungary 7 Department of Petrology and Geochemistry, Eötvös Loránd University, Budapest, Hungary 8 MTA ATOMKI K-Ar Laboratory, Debrecen, Hungary 9 Institut für Geologie Technische Universität Freiberg, Germany Contact: [email protected]

Large explosive volcanic eruptions can have significant impacts over wide areas and provide tephras deposited over several hundred kilometres. These tephra horizons are important marker layers helping correlating sedimentary sequences accumulated in different depocenters. During the Miocene, eruptions of various magmas occurred in the Carpathian- Pannonian Region. Using high-precision zircon geochronology, Lukács et al. (2018) showed that a massive silicic volcanic eruption phase occurred between 18 and 14.4 Ma and this could be considered the largest volcanism in Europe for the last 20 Myr. Within this, at least three large explosive eruption events were recognized (Mangó ignimbrite eruption at 17.055±0.024 Ma, Demjén ignimbrite eruption at 14.880±0.014 Ma and Harsány ignimbrite eruption at 14.358±0.015 Ma), each providing large amount of volcanic ash. These ignimbrites occur in the largest thickness and in fresh appearance in the Bükkalja volcanic field, Northern Hungary. Lukács et al. (2002) used melt inclusion compositional data, while Harangi et al. (2005) provided both mineral chemical signatures as well as in-situ trace element data of glass shards to correlate the scattered deposits in this area, which could be close to the eruption centers. The cumulative eruptive material during this ignimbrite flare-up episode is estimated to have been more than 4000 km3, implying that these three main eruptive events could eject several 100’s km3 volcanic ash. Such large volcanic material could presumably cover large areas. Although they could have undergone alteration and local redeposition, zircons could be effectively used for correlation. These minerals could preserve both the age of eruptions and its trace element composition reflect the erupted magma. Lukács et al. (2015) demonstrated that the Demjén and Harsány ignimbrites could be readily distinguished based on zircon trace element fingerprints.

Using zircon perspective correlation, silicic volcanic formations in the Carpathian-Pannonian Region can be correlated with the three main eruption events, emphasizing their regional impact. As a few examples, the Ipolytarnóc ignimbrite (Northern Hungary) could belong to the Mangó ignimbrite eruption, several volcanic deposits in the western Mecsek Mts (Southern Hungary) can be correlated with the Demjén ignimbrite, and the Dej tuff appears to have a strong affinity to the Harsány ignimbrite.

The new zircon U-Pb age data, trace element and Hf isotopic compositions can be used also to conduct correlation of the three main silicic volcanic events with the volcanic ash materials accumulated in various sub-basins along the northern Mediterranean (Alpine forelands) during the Paratethys era (e.g. Rocholl et al., 2017) and the volcanic ash layers in the La Vedova marine sedimentary section near Ancona, east-central Italy (Wotzlaw et al., 2014). Correlation and chronostratigraphy of Mid-Miocene sedimentary deposits help to refine local lithostratigraphy and the regional stages of the Paratethys, and contribute to connecting the sequences to global events (i.e. precise timing and cross-correlation of geomagnetic polarity 56 reversals, sea-level cycles, astronomic and climatic events, flora and fauna evolutional stages). Lukács et al. (2018) demonstrated that many of these volcanic ash occurrences show a remarkable fit with one of the three eruption events occurred in the Pannonian basin. This implies that volcanic ash of these eruptions spread and deposited over 1000 km distance along the northern Alps and the central Mediterranean and this could consistent with periodical easterly winds during the Mid-Miocene.

In addition to the dominant Mid-Miocene silicic volcanic formations, a few centimetres thick, coarse ash layer was found in the Northern Mecsek Mts (at Danitzpuszta, Southern Hungary) within an Upper Miocene marl formed in the Lake Pannon. Dating of such lacustrine successions is often problematic. This is the case also with the sediments of the Lake Pannon, where more than 4 km thick deposits accumulated during a time span of approximately 7 million years. They are subdivided mainly using mollusc and dinoflagellate biozones. This newly recognized tephra could help to refine the chronostratigraphic framework.

The tephra bed has a mineralogical assemblage (plagioclase, K-feldspar, biotite, amphibole, augite, aegirineaugite, aegirine and apatite) typical of alkaline magmas and resemble that characterizes the alkaline trachytes of the presently buried Pásztori volcano (Harangi et al., 1995; Harangi, 2001), located in over 200 km distance from the tephra location, in the northwestern Pannonian Basin. Composition of the clinopyroxenes supports the presumed tephra origin from the Pásztori volcano. The volcanic eruptions at Pásztori could have occurred at around 11.4 ± 0.6 Ma to 12.3 ± 0.8 Ma based on zircon fission track dating, whereas the new Ar-Ar age of the Danitzpuszta tephra yields 11.25 ± 0.21 Ma. This latter age is concordant with the (U-Th)/He age on apatite (11.83 +2.82 -0.67 Ma) and K/Ar age on biotite (11.8+/-0.2 Ma) and support that this tephra is the distal volcanic ash material of one of the large explosive events of the Pásztori volcano that was previously unnoticed.

References Harangi (2001), Acta Vulcanologica 13:(1), 25-39. Harangi et al. (1995), Acta Vulcanologica 7:(2), 173-187. Harangi et al. (2005), Volcanology and Geothermal Research, 143(4): 237-257. Lukács et al. (2002), Acta Geologica Hungarica 45:(4), 341-358. Lukács et al. (2015), Contributions to Mineralogy and Petrology, 170(5): 52. https://doi.org/10.1007/s00410-015-1206-8 Lukács et al. (2018), Earth-Science Reviews, 179: pp. 1-19. Rocholl et al. (2017), International Journal of Earth Sciences. https://doi.org/10.1007/s00531-017- 1499-0 Wotzlaw et al. (2014), Earth and Planetary Science Letters, 407: 19-34.

Research was supported by the Hungarian Scientific Research Fund (OTKA/NKFIH) projects PD112584 and PD 121048 and the János Bolyai Research Scholarship of the Hungarian Academy of Sciences to R.L.

57

O 5.4 in Oral session 5: 27.06.2018, 17:15-17:30

Cryptotephra investigation in the Carpathian Mountains, Romania 1 1 2 3 4 REBECCA KEARNEY , PAUL ALBERT , RICHARD STAFF , PÁL IOANA , VERES DANIEL , MAGYARI 5 6 ENIKŐ , BRONK RAMSEY CHRISTOPHER 1 Research Laboratory for Archaeology and the History of Art, University of Oxford, Dyson Perrins Buildings, South Parks Road, Oxford, OX1 3QY, UK 2 Scottish Universities Environmental Research Centre, University of Glasgow, East Kilbride, South Lanarkshire, G75 0QF, UK. 3 Isotope Climatology and Environmental Research Centre (ICER), Institute for Nuclear Research, Hungarian Academy of Science, H-4026, Debrecen, Bem tér 18/c, Hungary 4 Institute of Speleology, Romanian Academy, Clinicilor 5, 400006 Cluj-Napoca, Romania. 5 Eötvös Lóránd University, MTA-MTM-ELTE Research Group for Paleontology, Department of Environmental and Landscape Geography, Pázmány P. stny. 1/C, H-1117 Budapest, Hungary. 6 RLAHA, University of Oxford Contact: [email protected]

Our understanding of the timing and drivers of past abrupt climate change can be improved by the integration of disparate palaeoclimatic records. However, chronological uncertainty associated with dating errors on individual climate records prevents us from carefully interrogating whether past climatic variability has been spatially synchronous or asynchronous. Cryptotephra (non-visible volcanic ash) provides a key tool to precisely synchronise palaeoenvironmental records over thousands of kilometres, in addition to building and improving local chronological models.

Here, we present the first, distal cryptotephra record from two sites in the Southern Carpathian Mountains (Romania). Our crypto-tephrostratigraphic investigations concentrate on the Late-glacial portions of the Lake Lia and Lake Brazi sedimentary sequences. We have identified several discrete cryptotephra layers within these two records. Major and minor element volcanic glass geochemistry (Electron microprobe analysis and LA-ICP-MS) reveals that the cryptotephra layers derive from multiple volcanic source regions (e.g. Aeolian Islands, Central Anatolia, Iceland). The ultra-distal occurrence of the Askja-S tephra in both records is one of the most significant findings as it dramatically extending the known south- eastern dispersal of ash from the Plinian eruption. New age constraints from these two Romanian lakes help further refine the age of the eruption to 10,824±97 cal yrs BP (Kearney et al., 2018). Crucially, Askja-S now offers a precise chronological tie-point facilitating the alignment of climate archives from NW Europe through into Eastern Europe immediately after the Preboreal climatic oscillation. The cryptotephra investigations presented here illustrate the significant potential of the central Carpathian Mountains as a location to integrate the tephrostratigraphic frameworks of disparate volcanic sources, and in doing so, providing a more robust chronological framework for palaeoclimate records in the region.

References Kearney, R., Albert, P.G., Staff., R.A., Pál, I., Veres, D., Magyari, E., Bronk Ramsey, C. 2018. Ultra- distal fine ash occurrences of the Icelandic Askja-S Plinian eruption deposits in Southern Carpathian lakes: New age constraints on a continental scale tephrostratigraphic marker. Quaternary Science Reviews, 188, 174-182.

58

O 5.5 in Oral session 5: 27.06.2018, 17:30-17:45

Tephra layer refining Middle Pleistocene chronology of Serbian loess 1 1 1 2 1 YU FU , QINGZHEN HAO , CHUNQING SUN , SLOBODAN MARKOVIĆ , ZHENGTANG GUO 1 Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, China 2 Physical Geography, Faculty of Sciences, University of Novi Sad, Serbia Contact: [email protected]

Loess deposits have long been regarded as one of the most important archives of Quaternary climatic evolution. Especially, middle Pleistocene loess, deposited in recent several glacial-interglacial cycles of various amplitude and duration, may provide important information about the impact of climate change on continental environment and its mechanisms. However, beyond the upper limit of OSL (optically stimulated luminescence) (~100 kyr) and radiocarbon dating (~ 50 kyr), chronology of middle Pleistocene loess mainly depends on orbital tuning, with the only independent age control of the Brunhes-Matuyama boundary, which hardly meets the requirements of further paleoclimatic investigations in higher resolution and precision. Fortunately, in Serbian part of Danube loess, which is considered to be the most complete loess-paleosol sequences over the past million years over Europe, several tephra layers interbedded in the deposit may provide more independent age controls in the middle Pleistocene interval.

We here focused on a visible tephra layer interbedded in the loess unit V-L4, estimated corresponding to MIS 10. The tephra layer is around 1 cm thick in yellowish brown color and mainly consists of coarse-silt-sized grains, and showed an abrupt increase in magnetic susceptibility. Glass shards are orange to brown in color, with thick-walled, cuspate shards and pumiceous shards morphology. The mineral assemblage is made up of clinopyroxene, plagioclase, sanidine, biotite and apatite.

To determine its origin, in situ major elements of glass shards and clinopyroxene were determined by electron microprobe analyses (EPMA), and glass shards 87Sr/86Sr and 143Nd/144Nd ratios were obtained by a thermal ionization mass spectrometry (TIMS). The glass shards were altered and showed low oxide totals (76-87%) and depletion of alkalies, incapable of any correlation. The clinopyroxene showed fassaitic diopside composition, with relatively constant CaO content. The 87Sr/86Sr ratio was 0.711655 and the 143Nd/144Nd ratio was 0.512126.

Volcanoes reported to have eruptions around the period of V-L4 deposition included Alban Hills, Vulsini, Roccamonfina and Sabatini. Comparison of clinopyroxene composition and glass 87Sr/86Sr and 143Nd/144Nd ratios with products of these volcanoes suggested that the tephra we studied was product of Alban Hills. Previous studies showed that along the eruption history of Alban Hills, the clinopyroxene composition had undergone an evolution towards wider distribution range. The clinopyroxene composition of our tephra sample was quite similar to product of an eruption occurred at 351-357 ka, named the Villa Senni Eruption. Therefore, the tephra layer in Serbian loess V-L4 is preliminary dated by 351-357 ka.

The clinopyroxene composition of this tephra layer also coincides with that of the Bag Tephra, suggesting they might be isochronous deposits. The Bag Tephra is a widespread tephra layer interbedded in Quaternary loess deposits along the Danubian valley of Hungary and Slovakia, and speculated to be product of Villa Senni eruption, which however lacks geochemical evidence (Pouclet et al., 1999). The results of this study possibly proved this linkage.

The age of tephra layer in V-L4 provides a solid independent age for the chronology frame of Serbian loess and its pedostratigraphic and climatostratigraphic coherence with Chinese 59 loess (Song et al., 2018), shedding new light in future land-sea correlation and environment dynamics study.

References Pouclet, A., et al. "The Bag Tephra, a widespread tephrochronological marker in Middle Europe: chemical and mineralogical investigations." Bulletin of Volcanology 61.4 (1999): 265-272. Song, Yang, et al. "Magnetic stratigraphy of the Danube loess: A composite Titel-Stari Slankamen loess section over the last one million years in Vojvodina, Serbia." Journal of Asian Earth Sciences 155 (2018): 68-80.

O 5.6 in Oral session 5: 27.06.2018, 17:45-18:00

Tephrostratigraphy and chronology of the Lake Ohrid DEEP site record of the last 1.4 Ma 1 2 3 4 NIKLAS LEICHER , BIAGIO GIACCIO , GIOVANNI ZANCHETTA , ALEXANDER FRANCKE , ROBERTO 5 6 7 8 9 SULPIZIO , SEBASTIEN NOMADE , JANNA JUST , PAUL G. ALBERT , EMMA L. TOMLINSON 1 Institute of Geology and Mineralogy, University of Cologne 2 Istituto di Geologia Ambientale e Geoingegneria, CNR, Roma, Italy 3 Dipartimento di Scienze della Terra, University of Pisa, Pisa, Italy 4 University of Wollongong, Wollongong Isotope Geochronology Laboratory, Wollongong, Australia 5 Dipartimento di Scienze della Terra e Geoambientali, University of Bari, Bari, Italy + Istituto per la Dinamica dei Processi Ambientali (IDPA) CNR, Milan, Italy 6 Laboratoire des sciences du climat et de l’environnement, CEA/CNRS/UVSQ, Université de Paris-Saclay, Gif-Sur-Yvette, France 7 Faculty of Geosciences, Marine Geophysics, University of Bremen, Germany 8 RLAHA, University of Oxford, Oxford, UK 9 Department of Geology, Trinity College Dublin, Dublin, Ireland Contact: [email protected]

The sedimentary archive of Lake Ohrid, located on the Balkan Peninsula, was drilled in 2013 within the scope of the International Continental Scientific Drilling Program (ICDP) and the project “Scientific Collaboration on Past Speciation Conditions in Lake Ohrid” (SCOPSCO). It is one of the very few terrestrial archives that cover the last 1.4 Ma continuously and provide high-resolution information about the regional geological and paleoclimatic history, as well as triggers of biological evolutionary patterns and endemic biodiversity.

At the main drill site DEEP, located in the centre of the lake, a continuous composite profile (584 m) has been compiled out of 4 neighbouring bore holes. Lithological information from the DEEP site record implies shallow water conditions between 584 and 456 m. The deposition of this sedimentary facies represents the basin formation and the establishment of the lake between 1.9 and 1.4 Ma ago. Above 456 m sediment depth, biogeochemical and sedimentological proxy data indicate pelagic sedimentation over the last 1.4 Ma and reflect global glacial/interglacial cycles.

Within the upper 456 m of the sequence 56 tephra horizons were identified until now, out of which 48 are macroscopic tephra layers. Juvenile glass fragments of all of these layers were analysed for their major element composition using SEM-EDS/WDS systems. Their geochemical fingerprint suggests a volcanic origin exclusively from the Italian comagmatic provinces.

The tephrostratigraphic work and correlation of tephra to other records is limited by the lack of other reference records, as only few other Mediterranean archives cover the period from the Early Pleistocene up to recent times continuously. These records include the Calabrian Ridge core KC01B (Insinga et al., 2014) and the peat record from Tenaghi Philippon, Greece 60

(Wulf et al., 2018). However, so far tephrostratigraphic information of these two records are published only for the late Pleistocene (max. ca. 192 ka), from which also additional information from other shorter records exist. The tephrostratigraphic knowledge about the period older 0.2 Ma is based on individual, non-continous records from various mid-distal Italian intermontain continental basins or continental margin marine basins only (e.g. such as Sulmona, Acerno, Mercure, Montalbano Jonico, or the Tiber deltaic succesion) and still relatively poorly understood. Therefore, the Lake Ohrid record provides the unique opportunity to investigate the distal dispersal of tephra from the Italian volcanoes in a continuous record covering the last 1.4 Ma for the first time.

In the interval between 456 and 248 m, representing 1.4 – 0.65 Ma, 15 tephra layers were identified, three of which between 290 and 267 m could successfully be correlated with 40Ar/39Ar dated tephra layers from the Sulmona basin and Montalbano Jonico marine succession. These tephra layers bracket the Brunhes/Matuyama transition and allow a detailed investigation of the timing of the last magnetic pole reversal across different archives. The (so far) uncorrelated 12 tephra layers provide valuable new information about the volcanic activity especially for the time interval >0.8 Ma, and could become important first marker horizons for future tephrostratigraphic work in the region.

The upper 248 m (<0.65 Ma) contain 41 tephra layers that are important chronological tie points and marker horizons. Thirteen of those layers are described and correlated to known tephra layers in other records in Leicher et al. (2016) and provided the first order ties points for developing the age model for the last 650 kyr (Francke et al., 2016). New investigations could also allow the correlation of two tephra layers in MIS 6 with eruptions originating from Pantelleria, which were also found in ODP Site 963A in the Sicily Channel (Tamburrino et al., 2012). Trace element compositions of single glass shards of tephra layers from unknown volcanic eruptions were determined by LA-ICP-MS in order to obtain more information about the origin of these eruptions. We could identify new, so far unknown eruptions from the Italian volcanic centres e.g. the Aeolian Arc or the Campanian volcanic zone. In combination with isotopic studies (Sr, Nd) this methodological approach shall also be applied for tephra layers of the interval older 0.65 Ma.

First cryptotephra studies of selected intervals of the DEEP site record emphasize the tephrostratigraphic potential of the Lake Ohrid record. Downcore XRF data indicate six cryptotephra horizons within the sediments of the last 15 ka. Their isochrone position was precisely determined by physical separation and glass shard concentration counting. During MIS 11, the recognition of a cryptotephra correlated with the Vico β eruption (ca. 410 ka) provides fundamental chronological information for a high-resolution pollen study.

The continuous progress of the tephrostratigraphic investigations of the DEEP site has provided new important chronological information that have been incorporated in the age model, so consolidating its soundness and reliability. The small grain size of crystals of the Lake Ohrid tephra layers has so far prevented direct radioisotopic dating of these layers, but ages of radioisotopically dated equivalent tephra from more proximal sites were imported to the Ohrid record. All imported 40Ar/39Ar ages were recalculated with the same constants and flux standards in order to obtain a homogenous set of ages and provide together with the magnetostratigraphy the primary data for the age-depth model. Additional age information are provided by tuning biogeochemical proxy data to orbital parameters. The partly independent and well-established chronology is the backbone to fulfil the major aims of the SCOPSCO project and for investigating the history of the regioanl paleoenvironmental variablilty and the origin of Lake Ohrid.

References Francke A., et al. 2016. Sedimentological processes and environmental variability at Lake Ohrid (Macedonia, Albania) between 637 ka and the present. Biogeosciences, 13, 1179-1196. 61

Insinga D.D., et al. 2014. Tephrochronology of the astronomically-tuned KC01B deep-sea core, Ionian Sea: insights into the explosive activity of the Central Mediterranean area during the last 200 ka. Quat. Sci. Rev., 85, 63-84. Leicher N., et al. 2016. First tephrostratigraphic results of the DEEP site record from Lake Ohrid (Macedonia and Albania). Biogeosciences, 13, 2151-2178. Tamburrino S., et al. 2012. Major and trace element characterization of tephra layers offshore Pantelleria Island: insights into the last 200 ka of volcanic activity and contribution to the Mediterranean tephrochronology. J. Quat. Sci., 27, 129-140. Wulf, S., et al. 2018. The marine isotope stage 1–5 cryptotephra record of Tenaghi Philippon, Greece: Towards a detailed tephrostratigraphic framework for the Eastern Mediterranean region. Quat. Sci. Rev., 186, 236-262.

Oral session 6

O 6.1 in Oral session 6: 28.06.2018, 09:00-09:15

Tephrostratigraphy in Southeast Asia: towards unravelling the eruptive history of Sumatran Volcanoes 1 1 2 3 MARCUS PHUA , CAROLINE BOUVET DE MAISONNEUVE , HAMDI RIFAI , RINA ZURAIDA , SATISH 4 SINGH 1 Asian School of the Environment & Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore 2 Universitas Negari Padang, Kota Padang, Sumatera Barat 25132, Indonesia 3 Marine Geological Institute, Kota Bandung, Jawa Barat 40174, Indonesia 4 Institut de Physique du Globe de Paris, 75238 Paris, France Contact: [email protected]

Sumatra is host to at least 30 of ~130 recently/historically active volcanoes across the vast Indonesian archipelago. These volcanoes lie in close proximity to major cities in Indonesia such as Medan (2.5 million inhabitants), but also not too distant from highly populated countries like Singapore (5.6 million). And yet in spite of the inherent risk, the eruptive history of these volcanoes is poorly known, as only a handful have been studied and regularly monitored. To rectify this, we use tephrostratigraphy as a tool to unravel the history and behaviour of past Sumatran eruptions: their frequency, magnitude and spatial footprint. Tephra/cryptotephra sequences preserved in lacustrine, marine and peatland environments are the focal points of the study.

A 17.76 m sediment core MD16-3522 was collected from the north-east Indian Ocean (3.522°N; 92.946°E; 4417 m) in July 2016 during the MIRAGE I expedition on board R/V Marion Dufresne. Between 0 and 12.20 m below seafloor, three visible centimetre to decimetre-thick tephra layers were identified in the sediment core: i) MD16-3522-158-161 cm (Layer A); ii) MD16-3522-685-688 cm (Layer B); and iii) MD16-3522-1217-1219 cm (Layer C). Major element compositions of glass shards extracted from the three discrete tephra layers provide hints towards their volcanic source. Tephra layer A is geochemically correlated to the 73.88 ± 0.32 ka (Storey et al. 2012) Young Toba Tuff (YTT) eruption, whilst tephra layers B and C are determined to be geochemically distinct from the 501 ± 5 ka (Chesner et al. 1991) Middle Toba Tuff (MTT) and 788 ± 2.2 ka (Lee et al. 2004) Oldest Toba Tuff (OTT) layers. Tephra layers B and C are also clearly distinguishable in terms of major element geochemistry from the deposits of the Maninjau and Ranau calderas. Potassium- rich minerals such as sanidine – KAlSi3O8 and biotite – K(Mg,Fe)3AlSi3O10(OH,F)2 were hand-picked from the three discrete tephra layers and prepared for high precision single- and multiple-grain 40Ar/39Ar geochronology. In conjunction with major and trace element compositional characteristics, the 40Ar/39Ar ages obtained are expected to facilitate the correlation of the unidentified tephra layers B and C to their volcanic source provenance. 62

Ongoing work on this core is focused on: i) identifying tephra/cryptotephra layers in the remainder of the sediment core, with a particular focus in the upper two metres, ii) elucidating the trace element geochemical fingerprint of the three discrete tephra layers by LA-ICP-MS and iii) constraining the ages of the tephra/cryptotephra horizons using geochronogical methods such as 40Ar/39Ar geochronology, 14C dating and δ18O chronostratigraphy.

Groundwork has been laid for geophysical surveys and coring activities at identified lakes/peatlands in Western Sumatra and field activities are expected to proceed between the spring and summer of 2018. Although established in many parts of the world, the use of tephra/cryptotephra as a chronological tool has been largely underutilised in Southeast Asia. Establishing the tephrochronological framework throughout Sumatra is expected to yield much improved knowledge of the eruptive history of Sumatran volcanoes and provide the necessary information required for reliable volcanic hazard assessments that are vital to the mitigation of volcanic risks in the region.

O 6.2 in Oral session 6: 28.06.2018, 09:15-09:30

Identification of Lower Pleistocene widespread tephras associated with huge caldera-forming eruptions in Northeast Japan (Tohoku) using LA–ICP–MS and SEM–EDS analyses 1 2 2 3 4 TAKEHIKO SUZUKI , SEIJI MARUYAMA , TOHRU DANHARA , TAKAFUMI HIRATA , TOMOKO OJIMA , 4 5 HIROSHI MACHIDA , FUSAO ARAI 1 Department of Geography, Tokyo Metropolitan University 2 Kyoto Fission-Track Co., Ltd. 3 Geochemical Research Center, Graduate School of Science, The University of Tokyo 4 Department of Geography, Tokyo Metropolitan University 5 Gunma University Contact: [email protected]

Tephra layers as geochronological units act both as dated age markers (tephrochronology) and stratigraphic horizons (tephrostratigraphy) showing geological events such volcanic eruptions. However, the value of tephra layers without identified their source volcano is limited in the context of volcanology. Although more than a few hundred Quaternary tephra layers have been catalogued in and around the Japanese Islands during last five decades (Machida and Arai, 2003), there still many tephra layers of which the source volcanoes remain unknown due to scarcity of outcropping. Some of those have been correlated across the broad area stretching > 100 km, suggesting they may associated with huge eruptions rated at a VEI of 6–7. The Tohoku area, in the northeast part of Honshu (the main island) of the Japanese Islands, characterized by stronger activity of calderas and stratovolcanic formations from the Late Miocene to the early half of the Quaternary than present is one of the strongest candidate region for source of tephra layers of which source has not yet been identified. Connecting proximal tephras such as ignimbrite and distal tephra comprised of finer volcanic glass shards is worth not only the volcanology but also Quaternary studies in the Japanese Islands. To reveal these connection, improved fingerprinting and correlation techniques such as a combination of LA–ICP–MS and SEM-EDS technique has an advantage of analysis on the individual glass shard without unfavorable incorporation of coexisting mineral grains. Moreover, the LA–ICP–MS technique providing an efficient, accurate, and appropriately precise method for determining abundances of a wide variety of trace elements including REEs at low concentrations in individual glass shards has possibility for identification of the source area of tephras of unknown origin.

In this study, we discuss correlation of two widespread tephra layers originated from the Sengan geothermal region in the north Tohoku area and other two widespread tephra layers from the Aizu volcanic region in south Tohoku area using mainly combination of LA–ICP–MS and SEM-EDS technique. In ascending order, they are two tephras from the Sengan 63 geothermal volcanic region (Tmg-R4 Tephra: 2.0 Ma, Kd44-Naka Tephra: 1.968–1.781Ma) (Suzuki and Nakayama, 2007), two from the Aizu volcanic region (Sr-Asn-Kd8: 1.219 Ma, Sr- Kc-U8: 0.922–0.910 Ma) (Suzuki et al., 2017). They are composed of distal fall-out tephras and partly proximal ignimbrite. In previous study, proximal tephra such as ignimbrite of Kd44- Naka Tephra stratigraphically immediately above Tmg-R4 in Kanto to Kinki areas have remained unknown (Suzuki and Nakayama, 2007) although its distribution and eruption age are broader and younger than those of Tmg-R4. However, characteristic properties such as high content of Ba (> ca. 700 ppm) and similar composition of major elements of glass shard suggest that Kd44-Naka Tephra possibly derived from the Sengan geothermal region. In this study, we detected an undescribed ignimbrite here named the Ainosawa Ignimbritewith possibility of correlative to Tmg-R4 Tephra or Kd44-Naka Tephra in the Sengan geothermal volcanic region, then, examined widespread correlation of this ignimbrite. Additionally, we consideredthree distal tephras (Hirataike, Mitsumatsu, Yellow-IV and Yamada I volcanic ash layers) within the Osaka Group in Kinki area further from the Sengan geothermal and Aizu volcanic regions than from Kanto region where Tmg-R4, Kd44-Naka, Sr-Asn-Kd8 and Sr-Kc-U8 Tephras have been already recognized.

The distributions of Al2O3, FeO, CaO, Na2O, and K2O in four tephras determined by both LA– ICP–MS and SEM–EDS analyses can be distinguished from each other. Also, all element patterns oftrace element abundancesdetermined by LA–ICP–MS analyses shows typical pattern of tephras from Northeast Japan. Those of newly detected Ainosawa Ignimbriteare similar to those for Kd44-Naka Tephra identified by previous study, not to Tmg-R4 Tephra. Therefore, the proximal ignimbrite of Kd44-Naka Tephra is the Ainosawa Ignimbritein the Sengan geothermal region, and Kd44-Naka Tephra should be re-defined as the Sengan- Kd44 Tephra. Correlation of Hirataike volcanic ash layerwith Sengan-Kd44 Tephra indicates its broader distribution (~820 km SW) than previously expected. Yellow-IV and Yamada I volcanic ash layers are correlated with Sr-Asn-Kd8 and Sr-Kc-U8, respectively. Therefore, their distributions are also broader than those previously expected, showing necessary of recalculation of volumes of co-ignimbrite distal fall-out tephra.

Comparing element patterns oftrace element abundancesof tephras originated from other area, such as Kyushu, central Japan and Hokkaido,difference of the pattern is evident. It indicates sufficiency for searching source of unknown tephra. Moreover, this study revealedslight difference between the Sengan geothermal and Aizu volcanic regions although they are situated in Northeast Japan.

64

O 6.3 in Oral session 6: 28.06.2018, 09:30-09:45

Petrography, geochemistry and 40Ar/39Ar dating of YTT ash, Purna alluvial basin, Central India 1 2 AJAB SINGH , ASHOK K. SRIVASTAVA 1 Department of Geology, SGB Amravati University, Amravati, India 2 Department of Geology, SGB Amravati University Contact: [email protected]

The Purna alluvial basin with the spread of about 6,522 km2 is infilled with areno-argillaceous sediments ranging in age from Late Pleistocene to recent. These sediments show good development in both vertical and lateral profiles of the basin, however, good exposures are limited to river banks only having thickness of 15-20 meters. YTT ash in the basin area have been encountered at eight different localities viz., Masod, Parad, Bhog Nala, Hudki, Sangwa, Kapileshwar, Gandhigram and Andura, lying along the main channel of Purna river and its tributaries. The ash is powdery, light gray, yellowish brown to grayish orange pink in colours within the thickness range of 0.5 to 3 m. It is preserved as lenticles, pockets and discontinuous beds in the middle part of river cut-sections represented by yellowish to grayish brown, laminated silty-clay. The host successions also show preservation of different types of calcretes i.e., root calcretes, nodular calcretes, rhizospheres, rhizolith balls and occasionally, laminar calcretes. The ash is clearly divisible into two i.e., primary and reworked. Primary ash is attributed with light gray colour, fine grained, 0.05 to 0.2 m thick and massive to laminated in nature. Reworked ash is yellowish brown to grayish orange pink, coarse grained, ~1 - >3 m thick and reveals several types of sedimentary structures i.e., parallel to cross laminations, sand size laminae, trough cross beddings and soft sediment deformational structures. Petrographically, this unconsolidated distal pyroclastic material consists of unidentifiable fine grained admixture, considerable amount of glass shards with varied morphologies and minor amount of mineral grains. The glass shards are colourless, transparent and occasionally vesicular in nature. These glassy grains are angular in shape with smooth, uncracked, unweathered and unaltered surfaces. On the basis of morphologies and bubble boundaries, these shards can be categorized into six types i.e., i) platy shards, ii) two bubble wall shards, iii) three bubble wall shards, iv) blocky shards, v) shards with elongated vesicles and, vi) pumice shards. The minerals identified in the ash are represented by quartz, sanidine, plagioclase, biotite, hornblende, pyroxenes, allanite, zircon and fe-ti oxides.

Major element analysis of handpicked, transparent and internally exposed glass shards using electron probe micro-analyzer shows high percentage of silica (72.03-79.74 wt%) followed by alumina (11.55-12.54 wt%), potassium (4.23-4.49 wt%) and sodium (2.03-2.47 wt%). These high values are comparable with those of YTT shards reported from other areas suggesting rhyolitic composition of magma. Trace element and REE data of glass shards, generated through ICP-MS are also comparable with YTT of Toba Caldera and other places including continental and oceanic deposits. Chondrite normalized plot for REE data shows negative gravity anomaly which implies high oxidation potential of the fractionating melt. Two sets of data for the absolute age determination through 40Ar/39Ar technique were also generated on handpicked glass shards, belonging to Gandhigram and Hudki areas. The analysis shows weight plateau and total fusion ages as 79±02 ka (2σ) and 77±05 ka respectively for Gandhigram locality and 77±05 ka (2σ) and 79±09 ka for Hudki area. These ages are very close to the youngest eruption of Toba Caldera, Sumatra, Indonesia.

65

O 6.4 in Oral session 6: 28.06.2018, 09:45-10:00

A late Pleistocene to Holocene cryptotephra framework for paleoenvironmental records from the Midwest to east coast of North America 1 2 1 3 4 BRITTA JENSEN , CONNOR NOLAN , LAUREN DAVIES , ALISTAIR MONTEATH , ROBERT BOOTH , 5 5 3 GILL PLUNKETT , SEAN PYNE-O'DONNELL , PAUL HUGHES 1 Earth and Atmospheric Sciences, University of Alberta 2 Department of Geosciences, University of Arizona 3 Department of Geography and Environment, University of Southampton 4 Earth and Environmental Sciences, Lehigh University 5 School of the Natural and Built Environments, Queen’s University Belfast Contact: [email protected]

Ombrotrophic peat bogs are a valuable source of paleoclimate data in the northern portions of North America. These bogs are also excellent repositories for cryptotephra- volcanic ash deposits not visible to the naked eye. While widely utilized in Europe, cryptotephra frameworks are in their relative infancy in North America, with only six published records - two from Alaska and four from the north-eastern portion of the continent. The latter tend to be limited in scope by reporting tephra(s) from narrow timeframes, with the exception of the original record by Pyne-O’Donnell et al. (2012) from Newfoundland. Here we report the tephrostratigraphy of three ombrotrophic peat bogs, Irwin Smith in northern Michigan, Bloomingdale Bog in upstate New York, and Sydney Bog in Maine, that collectively cover the last ca. 8000 years. This record is supplemented by an 8-12 ka snapshot from Long Bog in Wisconsin, and then integrated with existing studies and iterative radiocarbon modelling to develop a comprehensive cryptotephra framework for this region. Although the framework is dominated by new cryptotephra, there is a surprising cohesiveness in the ~2500 km transect with multiple tephras (e.g. Mount St. Helens We, White River Ash east, Newberry Pumice, Mazama) present across the entire region.

O 6.5 in Oral session 6: 28.06.2018, 10:00-10:15

Lake sediments provide the first eruptive history for Corbetti, a high-risk Main Ethiopian Rift volcano 1 1 2 3 2 CATHERINE MARTIN-JONES , CHRISTINE LANE , NICK PEARCE , VICTORIA SMITH , HENRY LAMB , 4 5 6 7 FRANK SCHAEBITZ , FINN VIEHBERG , MAXWELL BROWN , UTE FRANK , ASFAWOSSEN ASRAT 1 Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK 2 Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB, UK 3 Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3QY, UK 4 Institute of Geography Education, University of Cologne, 50931 Köln, Germany 5 Institute for Geology and Mineralogy, University of Cologne, 50674 Köln, Germany 6 Institute of Earth Sciences, University of Iceland, 101 Reykjavik, Iceland 7 GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany Contact: [email protected]

A 2011 World Bank report found that 49 of Ethiopia’s 65 known Holocene volcanoes pose a significant threat to the surrounding population. Ethiopia’s southernmost large volcanic system, Corbetti, is located in the densely populated Main Ethiopian Rift (MER), and has only one documented Holocene eruption. Reliable hazard forecasting requires long-term and comprehensive records of past volcanism. In tropical developing regions, like Ethiopia, populations live alongside volcanoes which have no eruption record and where proximal volcanic deposits are often poorly preserved. Any hazards assessments for volcanoes like Corbetti are therefore highly uncertain. 66

Lake sediments records offer an alternative means of accurately establishing past eruption frequency and magnitude, that by-passes inaccessible or weathered outcrops. Here we use volcanic ash (tephra) layers preserved in stratigraphically-resolved sediments from three MER lakes to provide the first record of Holocene volcanism for Corbetti. The tephrostratigraphy shows that Corbetti has erupted explosively throughout the Holocene at an average return period of ~900 years. Based on the thickness and dispersal of the tephras, at least six eruptions were of a large magnitude, and there were four eruptions in the past 2000 years. Future explosive eruptions are likely and these could have significant societal impacts, they could blanket nearby Awassa and Shashamene, home to ~260,000 people, with decimetres of pumice and ash deposits.

Our data indicate that the threat posed by Corbetti has been significantly underestimated. These data can be used to refine regional volcano monitoring and develop evacuation plans. This lake sediment-tephrostratigraphic approach shows significant potential for application throughout the East African Rift system, and is essential to understanding volcanic hazards in this rapidly developing region.

O 6.6 in Oral session 6: 28.06.2018, 10:15-10:30

Timing and dispersal of Middle Pleistocene caldera-forming eruptions in the Ethiopian Rift 1 2 1 1 3 CELINE VIDAL , KAREN FONTIJN , CHRISTINE LANE , CLIVE OPPENHEIMER , YVES MOUSSALLAM , 4 4 5 6 GEZAHEGN YIRGU , AMDEMICHAEL ZAFU , PAUL MOHR , FRANCES WILLIAMS , ALFONSO BENITO 7 8 CALVO , DAN BARFOD 1 University of Cambridge, UK 2 University of Oxford, UK 3 IRD, Universite Blaise Pascal, France 4 Addis Ababa University, Ethiopia 5 University College Galway, Galway, Ireland 6 University of Adelaide, Australia 7 Centro de Investigación sobre la Evolución Humana, Spain 8 University of Glasgow, UK Contact: [email protected]

While recent studies suggest the presence of Homo sapiens in north Africa circa 300,000 years ago (Middle Pleistocene), the East African Rift remains a critical region for understanding human evolution and its relationships to environmental, geomorphological and climatic stimuli. Numerous hypotheses proposed to link characteristics of the Rift environment and climatic change to hominin paleodemography, yet little attention has been paid to the role that volcanism played in shaping the Rift habitability. The Main Ethiopian Rift (MER) hosts more than a dozen of Quaternary caldera volcanic complexes suspected to have formed during the Middle Pleistocene. New Ar-Ar dates suggest that the seven largest calderas of the MER formed between 360,000 and 100,000 years ago, during a major pulse of explosive activity. These eruptions produced widespread tephra fallout deposits and filled the Rift valley with ignimbrite, which drastically remodelled the landscapes and disrupted ecosystems and hydrological systems, and potentially isolated populations in regions of the Rift. We integrate stratigraphy and geochemical analysis of whole-rocks and glasses of erupted products with new geochronological evidence to quantify the dispersal of these colossal events, by correlating proximal deposits with tephra in sediment records and at archaeological sites. We focus on the caldera-forming eruption of Shala volcano, which produced the largest Pleistocene caldera (17 km across) of the MER. The latter would occurred ca 180,000 years ago, more recently than previously estimated. Successful correlation of the deposits of the eruption to distal tephra horizons identified in lake sediment records show that widespread ash fallouts reached at least 300 km SW of Shala, near the Kenyan border. Further constraints on the tephra dispersal of these major eruptions in the 67

MER will constitute a robust database for modelling ecosystem impacts of these eruptions, and the implications for contemporary human populations.

Oral session 7

O 7.1 in Oral session 7: 28.06.2018, 11:30-11:45

Multi-criteria correlation of tephra deposits to source centres applied in the Auckland Volcanic Field, New Zealand 1 1 2 3 JENNI L HOPKINS , COLIN WILSON , MARC-ALBAN MILLET , GRAHAM LEONARD , CHRISTIAN 3 4 5 1 TIMM , LUCY MCGEE , IAN SMITH , EUAN SMITH 1 Victoria University of Wellington 2 Cardiff University 3 GNS Science 4 Macquarie University 5 Auckland University Contact: [email protected]

Tephrochronology is central to the reconstruction of eruptive histories of volcanically active regions. It is particularly helpful in resolving volcanic events occurring on timescales that are at shorter than the precision of traditional radiometric methods. However, in areas where proximal tephra deposits are poorly preserved or ambiguously sourced, there is currently no way of attributing distal deposits to their source, limiting their use in unravelling the volcanic history of such areas. We present a novel approach to overcome this problem using the late Quaternary basaltic Auckland Volcanic Field (AVF, New Zealand). We use geochemical compositions of the glass from tephra deposits and correlate this to geochemical signatures of proximal whole rock deposits. This approach was tested using artificial tephra created by crushing glassy whole-rock material and comparing the bulk and glass compositions with glass from the independently correlated tephra from the same eruption. We identify that incompatible trace elements and ratios (e.g. (Gd/Yb)) are least affected by fractional crystallisation processes, but display large variations related to the magmas’ mantle sources. As a consequence, trace elements have comparable signatures between whole rock and tephra, and in addition provide a forensic tool to distinguish different volcanoes formed by distinct magma batches. To strengthen our correlations, we detail a number of other criteria, including ages and locations of source centres and tephra horizons, thickness of tephra deposits and scale and style of eruptions from the field. With these combined criteria, we present a revised age-order model for the evolution of the AVF.

68

O 7.2 in Oral session 7: 28.06.2018, 11:45-12:00

Can we correlate variably weathered, phenocrystic intermediate tephras using both bulk and single grain analyses? An example from the Lepué Tephra, Southern Andean Volcanic Zone, Chile. 1 2 3 NICHOLAS PEARCE , BRENT ALLOWAY , CRAIG WICKHAM 1 Department of Geography & Earth Sciences, Aberystwyth University, Wales, UK 2 School of Environment, University of Auckland, Auckland, New Zealand 3 Department of Geography and Earth Sciences, Aberystwyth University, Wales, UK Contact: [email protected]

Single grain glass analyses for major and trace elements of intermediate (basaltic- andesite and andesite) tephras are often hampered by the presence of abundant phenocrysts which can contribute to the analysis of a glass shard. This is particularly problematic in laser ablation ICP-MS analysis (where the analysed volume is much greater than in EPMA) and ablated material will almost invariably contain plagioclase, adding Ca and Sr to the ablated material, and diluting incompatible elements. Bulk analyses of andesitic tephra can be valuable in that they overcome this issue with grain-specific methods, but these can incorporate enclosing sediment during deposition, or xenolithic/xenocrystic material from the eruption, and thus require careful sampling. However, andesitic tephra weather fairly rapidly and thus analysis and correlation may be further hindered by processes occurring in the soil- forming environment.

A prominent tephra marker, the Lepué Tephra, which is extensively distributed across the Southern Andean Volcanic zone, north-western Patagonia provides an excellent example of the problems associated with analysis and correlation (using single grain and bulk methods) of an andesitic tephra deposited in a high-weathering environment, and similar deposits are common in the SAVZ. Lepué Tephra, well dated at c. 11000 cal a BP from many lake and soil cover-bed sequences, has many characteristics typical of a phreatomagmatic eruption from a complex and compositionally zoned magma body. Sourced from Volcán Michinmahuida, Lepué Tephra can be correlated to an equivalent-aged pyroclastic flow deposit (Amarillo Ignimbrite), well exposed to the south-east of the volcano, although the source vent for these co-eruptive events is currently obscured by an ice field, which will have been more extensive at the time of eruption. The Lepué eruption of Volcán Michinmahuida proceeded from an initial rhyolitic phase into a main phase of basaltic–andesitic bulk composition. This main phase produced proximal dark brown-grey poorly sorted, scoriaceous lapilli tuff up to ~2.4 m thick, often containing accretionary lapilli up to 2-3 cm diameter, indicative of a wet eruption, and highly plagioclase-phyric glass shards. More distally, Lepué Tephra thins to a centimetre thick (or less) layer of irregular, discontinuous pods of crudely bedded, cemented fine- to medium-ash, enclosed by red-brown andic soils. Lepué Tephra closely overlies Last Glacial maximum deposits and underlies the Chana Tephra (previously referred to as Cha-1), the ~ 9.7 ka eruption of Volcán Chaitén.

Bulk sample analyses show a wide scatter of mobile elements (Rb, Sr, Cs, Ba) but less variable highly incompatible elements (Zr, Th, Hf, and Nb) showing consistent ratios, e.g. Zr/Nb (22 ± 3) and Zr/Th (50±8) in accretionary lapilli, proximal and distal samples, very similar to ratios for samples from ODP 1233D, which appears to be diluted by its enclosing sediment. However, REE and Y, generally regarded as immobile, behave in a similar manner to the more mobile elements, indicating the REE are also mobilised during weathering of the primary tephra. This mobility is evident in the normalised REE compositions of the bulk samples, particularly when considered in relation to their proximity to Michinmahuida. In distal deposits the REE display clear evidence of the “tetrad effect”, which causes REE concentrations to deviate from their usual smooth relationship with atomic number, leading to fractionation of the REE and giving irregular profiles, with cusps between Nd-Pm, at Gd, and between Ho-Er, separating the REE into four groups (tetrads). This process is invariably associated with the reaction between rocks and wate, and the formation of certain secondary minerals such as Fe and Mn oxides, or biological activity, both processes likely to occur in 69 this deep weathering environment. In addition, the thin, distal deposits of the Lepué Tephra, show a clear positive Ce anomaly, a result of the oxidation of Ce3+ to Ce4+ and its subsequent immobility as it forms CeO2, which is commonly associated with Fe-Mn oxides in oxidising environments.

Single fresh glass shard analyses from Lepué Tephra show that the highly incompatible/immobile elements Zr, Th, Hf and Nb show tightly constrained ratios (Zr/Th = 48±8, Zr/Nb = 23±3) which are indistinguishable from the bulk sample analyses. These data show the validity of using element ratios for comparison of bulk analyses with single grain analyses, even in such intensely weathered samples. During LA-ICP-MS, abundant plagioclase microcrysts in the glass shards however cause the concentrations of compatible and incompatible trace elements to spread over a wide range, but incompatible element ratios remain near constant. The ablation of increasing quantities of feldspar results in the enrichment of compatible elements (e.g. Sr) or dilution of incompatible elements (e.g. REE, Zr, Th etc.). This is particularly evident in Sr vs Zr where the analysed compositions result from a mixture between a glass end-member (in the Lepué Tephra <113 ppm Sr) and a feldspar end-member (~1200 ppm Sr, with no Zr). Incompatible elements thus range from high concentrations in the pure glass phase (~600-800 ppm for Zr, higher than the bulk analyses) to almost 0 ppm in analyses which are dominantly feldspar phenocrysts. The same pattern is repeated by all Lepué glass samples, indicating that the same relative proportions of glass and phenocrysts in shards were deposited across the fallout of the Lepué Tephra, suggesting there was no fractionation of this phenocryst rich component during the eruptions.

It is clear then, that when comparing distal glass shard analyses with proximal bulk data, account should be taken of the presence of phenocrysts and their impact on the analysed compositions. However, in phenocryst rich glasses, ratios of highly incompatible elements can be used to assess correlations, although these may be complicated by the crystallisation of minor phases (e.g. zircon in more evolved compositions). Additionally, element ratios of the most immobile incompatible elements (Zr, Hf, Nb, and Th) remain constant between bulk and single grain analyses even during extensive weathering. Thus, in some of the most unpromising situations, these highly incompatible element ratios from bulk and single grain analyses can provide a means for tephra correlation.

O 7.3 in Oral session 7: 28.06.2018, 12:00-12:15

Widespread dispersal of rhyolitic tephra from a subglacial volcano: linking the terrestrial palaeoenvironment with climate records 1 1 2 1 3 JONATHAN MOLES , DAVE MCGARVIE , JOHN STEVENSON , SARAH SHERLOCK , PETER ABBOTT , 1 1 FRANCES JENNER , ALISON HALTON 1 Faculty of Science, Technology, Engineering & Mathematics, The Open University, UK 2 British Geological Survey, UK 3 Department of Geography, Swansea University, UK; Institute of Geological Sciences, University of Bern, Switzerland; School of Earth and Ocean Sciences, Cardiff University, UK Contact: [email protected]

Volcanic eruptions that interact with ice (‘glaciovolcanism’) preserve a record of the presence and minimum thickness of ice at the time of each eruption. Reconstructions of past glacial environments, derived from the products of glaciovolcanic eruptions, are commonly linked to palaeoclimate records using radiometric dating techniques. Alternatively, a direct and precise link to palaeoclimate records could be achieved if tephra from the eruptions can be correlated between depositional settings. However, it has not previously been established whether a rhyolitic eruption at a subglacial volcano can result in widespread tephra dispersal.

Using geochemistry and geochronology, we correlate a regionally important tephra horizon – the rhyolitic component of North Atlantic Ash Zone II (II-RHY-1; ~55 ka) – and the Thórsmörk 70

Ignimbrite with glaciovolcanic rhyolites at Torfajökull volcano, Iceland. The eruption breached an ice sheet >400 m thick leading to the widespread dispersal of II-RHY-1 across the North Atlantic and the Greenland ice sheet. Locally, pyroclastic density currents travelled across the ice surface, depositing the Thórsmörk Ignimbrite in an area of little or no ice cover ~30 km from source.

The widely dispersed products of this eruption represent a valuable chronostratigraphic tie- line between terrestrial, marine and ice core palaeoenvironmental records. For the first time, glaciovolcanism-derived estimates of ice thickness and extent can be directly linked to the regional climate archive, which records the eruption midway through an abrupt cooling in climate at the end of Greenland Interstadial 15.2.

O 7.4 in Oral session 7: 28.06.2018, 12:15-12:30

Sizing up volcanic ash: how do we measure ash size, and why should we care? 1 1 1 KATHARINE CASHMAN , ALISON RUST , JENNIFER SAXBY 1 School of Earth Sciences, University of Bristol Contact: [email protected]

Size is a fundamental parameter of all tephra studies. Physical volcanologists use particle size to determine eruption intensity, ash dispersion modellers use size as an input parameter, communities worry about ash size from the perspective of health hazards and remobilisation potential. But size can be measured in different ways and, for non-spherical particles, geometric size (typically diameter of a volume-equivalent sphere), which is preferred by modellers, can be substantially than sieve size (used by volcanologists), optical size (used to measure the small particles, and also important for remote sensing applications) or aerodynamic size (used by the dust and aerosol communities). Here we will examine these different perspectives of size with particular emphasis on far-travelled volcanic ash particles, including cryptotephra. Importantly, the extreme anisotropy of typical (?) distal particles (e.g., flat plates) can explain some observed discrepancies between modelled and observed ash transport. For this reason, we suggest that documenting ash shape, in addition to size, is critical for reconciling perspectives of the various communities engaged in ash research.

O 7.5 in Oral session 7: 28.06.2018, 12:30-12:45

The isopach problem: the consequences of uncertainty in the thickness of the distal Mazama tephra 1 1 1 2 HANNAH BUCKLAND , KATHARINE CASHMAN , ALISON RUST , SAMANTHA ENGWELL 1 School of Earth Sciences, University of Bristol 2 British Geological Survey, Lyell Centre Contact: [email protected]

Tephra distribution patterns are classically presented as isopach maps. Isopachs are contours of equal deposit thickness that are typically informed by field measurements. Isopachs are useful for hazard assessment, erupted volume estimates, tephrochronology and ash dispersion models. However, the level of uncertainty in isopachs is varied and depends on the age of the deposit, the total area of deposition and the methods used to interpolate between thickness measurements. The degree of uncertainty is greatest for isopach maps of large magnitude, prehistoric eruptions. This is due to sparse field measurements, remobilised tephra and differential tephra compaction. The Mazama 71 eruption, which formed modern Crater Lake in Oregon ~7600 cal yr BP, is an eruption where the construction of isopachs has been limited by these factors.

Varied iterations of Mazama isopachs reveal the need to better constrain the depositional pattern of the tephra deposit, particularly >100km from source. Re-examining the Mazama deposit is motivated by an interest in the extent of remobilisation that can affect voluminous tephra deposits. We compiled information on the distal Mazama tephra from published sources. The information gathered is sourced from a wide range of disciplines including palaeoecology, techrochronology and physical volcanology. Overall, we found a lack of primary thickness data across the whole deposit. The data compilation also reveals the underreporting of the physical characteristics of the Mazama tephra when the research focus is not the eruption itself. Attributes such as grain size, ash shape and componentry are valuable for interpreting eruption dynamics and ash dispersion. When reported, these physical characteristics are often quantified differently by different disciplines. For example, tephra grain size can be described by the maximum grain diameter or as the mode of the grain size distribution. This study highlights of the advantages and challenges of integrating data from diverse research groups and disciplines.

Fieldwork on the distal Mazama tephra in the Walla Walla region USA (~450km from source), revealed the extensive remobilisation of the deposit, thus explaining the scarcity of primary tephra thickness measurements. We examined the primary and secondary tephra using backscattered electron imaging and found there are no physical features that indicate whether a sample has been remobilised or not. Both sample types were nearly pure volcanic glass shards and had no discrepancies in major element geochemistry. Therefore, to ascertain whether a tephra sample was remobilised or primary, we used drainage analysis to supplement our field observations and assess the potential ash input upstream of the locality. Where there was no upstream drainage we were confident that the ash could not have been remobilised by water or gravity and designated it as a primary deposit. However, it is still possible that tephra localities with no upstream ash input could have been remobilised by wind. Resuspended ash has long term implications for ash hazard assessment. The likelihood of ash resuspension posing a risk is amplified for large magnitude eruptions where a large proportion of the deposition occurs on land and in arid, high latitude regions, such as the Mazama eruption.

Assessing the tephra distribution pattern of the Mazama in terms of both thickness and grainsize has required the integration of data from a range of disciplines. Our intention is to combine the data with appropriate ash dispersion models to estimate primary distribution patterns. This will be valuable for correlation and cryptotephra studies that use the Mazama tephra as a stratigraphic marker. Assessing the primary deposition of the Mazama tephra will also illustrate the significance of tephra remobilisation following large magnitude eruptions. This is essential for hazard assessment and risk mitigation strategies following large eruptions. Tephra remobilisation also has implications for studies which rely on precisely dated tephra beds.

72

O 7.6 in Oral session 7: 28.06.2018, 12:45-13:00

Origins, complications and utility of variations in ash componentry 1 1 1 ALISON RUST , KATHARINE CASHMAN , KERI MCNAMARA 1 Earth Sciences, University of Bristol, United Kingdom Contact: [email protected]

Ash generated by the fragmentation of magma can have components that are glassy or crystalline, and dense or vesicular; it may also have variable glass compositions related to variable degrees of crystallization of the melt. The size, shape and abundance of crystals and bubbles ultimately depend on the storage and decompression history of the magma. Thus pre- and syn-eruptive processes can complicate the use of glass chemistries to correlate tephras, but they also provide additional types of data to fingerprint samples. Furthermore, the internal textures and external shapes of ash provide valuable constraints on eruption style and intensity in cases where the scarcity of sample sites precludes standard physical volcanology methods.

Where the fragmenting magma is very low-crystallinity (near-liquidus temperature), the glassy ash has the same composition as the bulk magma except for volatile species. However, if magma crystallizes as it ascends, the residual melt evolves in composition; consequently the chemistry of glassy ash particles is typically more silicic than its parent magma. Magmas with SiO2 >63% have generally crystallized sufficiently prior to eruption to reach a melt of rhyolite composition. In contrast, magmas of 55-60% SiO2 are very susceptible to ascent-driven crystallization, often generating a broad range of glass chemistries despite a uniform magma composition. Very fine ash from eruptions of intermediate to silicic composition is therefore likely to be rhyolitic regardless of the parent magma composition. This is a consequence of both the prevalence of rhyolite glass and early deposition of relatively dense and compact single-crystal particles. Consequently ash shape and bubble content are important determinants for long-range transport.

Sustained high-intensity explosive eruptions (Plinian) produce high proportions of glass shards. This is because magma ascent is too rapid to allow syn-eruptive crystallisation of microlites, except in hydrous mafic magmas. The result is a deposit dominated by microlite- free glass shards. Pulsatory (e.g. Vulcanian) eruption styles, in contrast, are characterized by inter-eruptive degassing and crystallization of shallow magma forming dense conduit plugs or domes; when this is suddenly ejected during an explosive eruption, it forms fragments with microlite-rich glass. The presence of both microlite-free and microlite-rich glass within the same eruption provides good evidence for both deep magma and shallow plug material being erupted by a down-going decompression wave. The utility of componentry for correlating tephras and assessing eruption style will be demonstrated with a case study from a volcano with a history of numerous eruptions but with limited preservation of ash.

73

Posters Poster session 1

P 1.1 in Poster session 1: 25.06.2018, 14:00-

Vegetation cover, slope and the preservation of terrestrial tephra layers 1 2 3 NICK CUTLER , RICHARD STREETER , ANDREW DUGMORE 1 School of Geography, Politics & Sociology, Newcastle University, UK 2 School of Geography & Sustainable Development, University of St Andrews, UK 3 School of Geosciences, University of Edinburgh, UK Contact: [email protected]

Terrestrial tephra layers provide insights into past eruptions and a means to assess future volcanic risks, hazards and impacts. However, the preservation of tephra deposits is likely to be affected by a variety of factors, including geomorphology (slope) and surface roughness (specifically, vegetation cover). We set out to investigate how the interplay of slope and vegetation influences the preservation of tephra deposits within the Quaternary stratigraphic record. Our study was based a data set of > 5500 tephra layer thickness measurements across a range of moderate (<35°) slopes and vegetation types in Iceland and Washington State, USA. We hypothesised that differences in vegetation cover at the time of deposition would drive variability in tephra layer thickness. We also believed that this effect would trump the influence of slope, when tephra deposits were relative thin (< 10 cm).We found that when vegetation cover was held constant, location on slope had no systematic impact on mean tephra layer thickness. Holding slope angle low (<5°) and constant, we observed systematic modifications of initial fallout thickness in areas of different vegetation types, with layers both thinning and thickening in areas of partial vegetation cover, and thickening within taller vegetation. Our findings have implications for the interpretation of Quaternary environmental record and the reconstruction of past volcanic fallout across areas of varied relief and strong vegetation gradients. Sloping sites with a consistent vegetation cover may produce the most reliable stratigraphic records of fallout whereas flat sites with varied vegetation might not. Furthermore, variability in tephra layers, often considered to be ‘noise’, may actually carry a signal of past vegetation cover.

Potential impact of vegetation structure on the preservation of a tephra deposit. 74

P 1.2 in Poster session 1: 25.06.2018, 14:00-

Tephra transformations: variable preservation of tephra layers from two well- studied eruptions 1 2 3 2 3 NICK CUTLER , RICHARD STREETER , LAUREN SHOTTER , JOSEPH MARPLE , JEAN YEOH , 3 ANDREW DUGMORE 1 School of Geography, Politics & Sociology, Newcastle University, UK 2 School of Geography & Sustainable Development, University of St Andrews, UK 3 School of Geosciences, University of Edinburgh, UK Contact: [email protected]

Terrestrial tephra layers are often used to reconstruct past volcanic eruptions. However, the conversion of fresh pyroclastic deposits into tephra layers is poorly understood. As a consequence, it can be difficult to assess how closely a preserved tephra layer represents the original deposit. To address this knowledge gap, we surveyed tephra layers emplaced by the 1980 eruption of Mount St Helens, USA (MSH1980) and the 1947 eruption of Hekla, Iceland (H1947). We compared our measurements with observations made shortly after the 1947 and 1980 eruptions, to calibrate the subsequent transformation of the tephra deposit. We expected the tephra layers to retain the broad characteristics of the original deposits, but hypothesized a) changes in thickness and mass loading due to re-working, and b) positive correlations between thickness and vegetation density. We observed some systematic changes in tephra layer properties with distance from the vent and the main plume axis. However, the preservation of the layers varied both between and within our survey locations. Closed coniferous forest appeared to provide good conditions for the preservation of the MSH1980 tephra, as expected; preservation of the H1947 deposit in sparsely vegetated parts of Iceland was much more variable. However, preservation of the MSH1980 deposit in sparsely vegetated areas of eastern Washington State was also excellent, possibly due to biocrust formation. We concluded that the preservation of tephra layers is sensitive to surface conditions at the time of the eruption. These findings have implications for the reconstruction of past eruptions where eruption plumes span regions of variable surface cover.

Conceptual diagram illustrating the post-depositional transformation of tephra layers.

75

P 1.3 in Poster session 1: 25.06.2018, 14:00-

A Lateglacial to mid Holocene tephrochronological record from Llyn Llech Owain, south Wales 1 1 1 2 2 GWYDION JONES , SIWAN DAVIES , NEIL LOADER , SARAH DAVIES , MIKE WALKER 1 Department of Geography, Swansea University, Singleton Park, Swansea, Wales, SA2 8PP, UK 2 Geography & Earth Sciences, Aberystwyth University, Llandinam Building, Penglais Campus, Aberystwyth, Wales, SY23 3DB, UK Contact: [email protected]

Late-glacial lacustrine sequences from NW Europe provide a wealth of information on the nature of, and environmental response to, the rapid and abrupt climatic events that characterised this period. Although, several records reveal distinct environmental and climatic changes akin to those observed in the Greenland ice-cores and other sequences, the exact phasing relationships are uncertain due to the dating limitations that preclude synchronisation. Here we explore the potential of utilising cryptotephrochronology as a high- precision tool for correlating a limnic sedimentary sequence in Wales with other disparate sequences across NW Europe. Very few geochemichally identified cryptotephra horizons have been reported within Welsh sequences. This study indicates the presence of 7 tephras that have been tentatively correlated to known eruptions: 2 North American tephras, 1 Italian tephra and 4 Icelandic tephras. A further 5 unknown tephra deposits have been analysed which may represent new eruptions. This study highlights the value of this site as one of the few full Late-glacial sequences preserved in Wales.

P 1.4 in Poster session 1: 25.06.2018, 14:00-

Tephrostratigraphy and tephrochronology of a 430 ka sediment record from the Fucino Basin, central Italy, unites Mediterranean and North Atlantic archives 1 2 3 4 NIKLAS LEICHER , BIAGIO GIACCIO , BERND WAGNER , GIORGIO MANELLA , GIOVANNI 4 4 5 5 6 ZANCHETTA , ELENORA REGATTIERI , SEBASTIEN NOMADE , ALISON PEREIRA , THOMAS WONIK , 7 8 8 9 10 MELANIE LENG , CAMILLE THOMAS , DANIEL ARIZTEGUI , MARIO GAETA , FABIO FLORINDO , 11 11 ELIZABETH NIESPOLO , PAUL RENNE 1 Institute of Geology and Mineralogy, University of Cologne 2 Istituto di Geologia Ambientale e Geoingegneria, Consiglio Nazionale delle Ricerche, Rome, Italy 3 Institute of Geology and Mineralogy, University of Cologne, Germany 4 Department of Earth Sciences, University of Pisa, Italy 5 Laboratoire des sciences du climat et de l’environnement, CEA/CNRS/UVSQ, Université de Paris-Saclay, Gif-Sur-Yvette, France 6 Leibniz Institute for Applied Geophysics, Hannover, Germany 7 7 Centre for Environmental Geochemistry, School of Biosciences, University of Nottingham, Nottingham, UK 8 Département des sciences de la Terre, Université de Genève, Geneva, Switzerland 9 Dipartimento di Scienze della Terra, University of Roma “La Sapienza”, Rome, Ital 10 Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 1, Roma, Italy 11 Department of Earth and Planetary Science, University of California, Berkeley, USA + Berkeley Geochronology Center, Berkeley, USA Contact: [email protected]

The Fucino Basin is the largest and probably the only Central Apennine basin hosting a continuous, thick lacustrine sediment succession documenting environmental history from the Early Pleistocene to recent historical times. The Fucino basin is downwind of the peri- Tyrrhenian volcanic centres (< 150 km) which makes it the best candidate available in the central Mediterranean to construct a long and continuous tephrochronological record. These tephra layers can be independently dated by the 40Ar/39Ar method and directly anchored to a 76 comprehensive time series of proxies contained in the lacustrine sediments. The Fucino lacustrine archive also provides the opportunity to extend the existing network of long terrestrial Mediterranean records (e.g. Dead Sea, Lake Van, Lake Ohrid and Tenaghi Philippon) to the west, a currently vacant area. Transferring chronological and stratigraphic information on paleomagnetic excursions and long- and short-term climate variability to North Atlantic climate records sets the framework for a better understanding of the spatio-temporal variability, the magnitude, and the different expressions of Quaternary orbital and millennial- scale paleoclimatic changes.

In June 2015, a ~82 m-long continuous sedimentary succession (F1-F3) was recovered from the eastern-central area of the Fucino Basin. The lithology of the lacustrine sediments is rather homogeneous and dominated by fine-grained lacustrine sediments composed of grey calcareous marl with variable proportions of clay and organic matter. Twentyone tephra layers constrain the chronology of the core back to 190 ka. The tephra layers originate from different Italian volcanoes, such as Campi Flegrei, Etna, Colli Albani, Ischia, Vico, Sabatini, the Neapolitan area and Latium region. They comprise key Mediterranean marker tephra layers, such as the Neapolitan Yellow Tuff, Campanian Ignimbrite, Y-7, C-22, X-5, and X-6. The tephrochronological information is the basis for the establishment of an age model for the F1-F3 core and to correlate geochemical and bio-geochemical data from F1-F3 to climate variability.

Based on these promising results, an international consortium of several scientists and institutions, including IGAG-CNR (Italy), IGG-CNR (Italy), INGV (Italy), LIAG (Germany), the BGS (UK), and the universities of Pisa (Italy), Rome (Italy), Cologne (Germany), and Geneva (Switzerland) provided funds for a new coring campaign and borehole logging. At the new site, the F4-F5 site, which is characterized by lower sedimentation rate, two ca. 86 m long cores were recovered in June 2017. Borehole logging was carried out in one of the two holes down to ca. 80 m.

The first core analyses comprise multi-sensor core logging (MSCL, GEOTEK Co.), line scan imaging, and XRF scanning (ITRAX, COX Ltd). Based on these data and on optical information after core opening, the individual, overlapping 1.5 meter long sediment sequences have been correlated to a core composite. Subsampling of discrete sediment samples and tephra horizons for future paleomagnetic, geochemical, sedimentological, geomicrobiological, and tephrostratigraphic studies started in autumn 2017 and yielded more than 130 tephra or cryptotephra horizons back to the MIS 12-MIS 11 transition (ca. 430 ka). The high number of such horizons forms the backbone to build an independent radioisotopically-anchored chronology that can be transferred via tephra correlations and/or paleoclimatic alignements to other records from the Mediterranean and North Atlantic realm.

77

P 1.5 in Poster session 1: 25.06.2018, 14:00-

The potential of tephra for paleao reconstruction and assessing landscape resilience 1 2 3 RICHARD STREETER , ANDREW DUGMORE , NICK CUTLER 1 School of Geography and Sustainable Development, University of St Andrews 2 Institute of Geography, University of Edinburgh 3 School of Politics, Geography and Sociology, University of Newcastle Contact: [email protected]

All tephra layers are transformed to greater or lesser degrees during the process of entrainment within the stratigraphic record, this process of transformation is determined by ecological and Earth surface processes. This paper highlights the possibilities for using tephra layer morphology as a way to understanding the resilience (likelihood of threshold change to an alternative stable state) of landscapes, past and present. Recent research has shown that when tephra falls onto vegetated surface its thickness reflects aspects of the small-scale vegetation patterning and structure. Vegetation patterning may reflect levels of environmental stress. Therefore variations in tephra thickness are likely to preserve information that can be used to assess the resilience of the land surface at the time of the eruption. Variations in tephra thickness have been found to contain early warning signals of threshold transitions (effectively a measure of resilience) in land surface states in contemporary tephra layers in Iceland. This approach has applications for understanding contemporary land surface resilience in areas of tephra fallout but could potentially be applied to the considerable stratigraphic archive of cm-scale past tephra layers, giving us qualitative information on the state of the land surface (vegetation patterning and the presence of erosion spots) that would be very difficult to obtain from other proxies. This information would be useful for archaeologists and geographers who wish to understand human-environment interactions and assess resilience in combined socio-ecological systems over millennial time scales.

P 1.6 in Poster session 1: 25.06.2018, 14:00-

Distal – ultradistal: Visible tephra layers in Lake El’gygytgyn, Siberia, Far East Russian Arctic 1 2 3 2 CHRISTEL VAN DEN BOGAARD , B.J.L. JENSEN , N.J.G. PEARCE , D.G. FROESE , M.V. 1 4 5 PORTNYAGIN , V.V. PONOMAREVA , V. WENNRICH 1 GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany 2 University of Alberta, Canada 3 Aberystwyth University, Wales, UK 4 Inst. of Volcanology and Seismology, Petropavlovsk-Kamtchatsky, Russia 5 University of Cologne, Germany Contact: [email protected]

Fallout tephra layers from explosive volcanic eruptions represent isochronous horizons independent from the environment in which they are deposited and the distance from their source volcanoes. They are highly valuable for the correlation to other terrestrial and marine climate records.

Here we show a record of tephra layers from Lake El-gygytgyn sediment core, from Western Beringia, 100 km north of the Arctic Circle. Western Beringia is the Eurasian half of Beringia, a large region extending from Eastern Siberia to far north-western Canada that was never glaciated. This resulted in exceptionally well-preserved paleoenvironmental archives that go well beyond the last glacial-interglacial cycle. While in Eastern Beringia (i.e. Yukon and Alaska) tephra layers are abundant and are well-established as valuable tools to date and 78 correlate sedimentary archives, in Western Beringia (i.e.arctic and subarctic eastern Russia) there little is known about volcanic deposits.

Lake El’gygytgyn was cored in the frame of the International Continental Scientific Drilling Program (ICDP), and retrieved more than 318 m of sediment spanning Mid-Pleistocene to Present.

Eight visible tephra layers (T0-T7) that are up to several centimeters thick were identified in the cores. The ages of the tephra according to the stratigraphy range from ca 45 ky to 2.2 My old. However, the closest volcanic field to lake El’gygytgyn is more than 300 km away and volcanoes with known explosive eruptions that have been active during the Late Neogene are more than 1000 km away in the Kurile-Kamchatka-Aleutians Arc and Alaska Peninsula. This implies that El’gygytgyn holds a record of distant very large magnitude eruptions, which must have been distributed widely over western Beringia.

Each individual visible tephra layer was petrologically described and geochemically characterized. Major, minor, trace element and Pb isotope composition of single shards were determined. Major and minor elements were performed in two laboratories (at University of Alberta, Edmonton and at GEOMAR, Kiel), these laboratories host comprehensive data bases of the potential source volcanoes. Both EMPA laboratories contributed to the recent INTAV (International Quaternary Association’s focus group on tephrochronology) comparison of tephrochronology laboratories. Both instruments produce data sets that are identical within statistical deviations, and allow direct comparison of the data sets and to their data bases.

Based on major, and trace-element geochemical distribution, the tephra layers from Lake El’gygytgyn are characterized by a subalkaline composition, and likely originate from a subduction-related tectonic setting rather than from intra-continental vents. Collectively, the major, trace and isotope geochemical data suggest that the Kurile–Kamchatka–Aleutian Arc and Alaska Peninsula volcanoes are the most likely sources for the eruptions.

Pb isotope data indicate a Kamchatkan volcanic source for tephra layers T0–T5 and T7. For tephra T6, Pb isotopes suggest a source in the Aleutian Arc, and while an Alaskan source is possible, there is presently no known tephra that can be correlated to this layer.

The source volcanoes for the tephras T0–T7 are not known at this time, they still offer a unique potential for future correlation of terrestrial and marine sites. The thickness of the Lake El’gygytgyn tephra deposits, more than 1500 km from any potential sources, suggests they are widely distributed, and thus are likely present in numerous depositional settings/archives.

The geochemistry presented here should allow for the future identification of these tephra, their linking to other terrestrial and marine deposits and eventually to recognition of their source volcanoes. Ultimately these tephra beds from Lake El’gygytgyn will provide the basis for a robust tephrostratigraphic framework for western Beringia that we predict will develop quickly now that the presence of tephra beds in this region is known.

79

P 1.7 in Poster session 1: 25.06.2018, 14:00-

New occurrences of the widespread 1254 C.E. tephra in Antarctic ice and identification of Rittmann volcano, Antarctica as the eruptive source. 1 2 PHILIP KYLE , M.J. LEE 1 Earth & Environmental Science, New Mexico Tech 2 Korea Polar Research Institute, Incheon 406-840, South Korea Contact: [email protected]

Deep Antarctic ice cores, especially those from West Antarctica have a rich tephra record. Extensive Holocene and Quaternary volcanism in West Antarctica and the McMurdo Volcanic Group in the western Ross Sea are the most important sources of these tephra. A trachytic tephra erupted about 1254 C.E. has previously been identified in 5 ice cores from East and West Antarctica. Using electron microprobe analyses, we have now identified the tephra in an ice core at Styx Glacier in northern Victoria Land. We also have identified the tephra, using major and trace element data, in a blue ice patch on the Transantarctic Mountains near Brimstone Peak in South Victoria Land. A tephra in a sediment core from the Ross Sea has many similarities in composition and may be a correlative of the 1254 tephra. It has been proposed that the eruptive source of the 1254 tephra was The Pleiades volcanic complex in northern Victoria Land but there is little supporting evidence for this correlation. Rittmann volcano, in northern Victoria Land, is now considered the source of the 1254 tephra. A volcanic breccia, presumably formed by a large explosive pyroclastic eruption at Rittmann volcano, has glassy fiamme-like clasts. Electron microprobe analyses of the glass and some whole rock analyses of lavas have trachytic compositions identical to the 1254 tephra. The Rittmann 1254 tephra is spread over 2000 km from its source and is the most significant tephrochronological marker in Antarctic ice cores. The tephra has been important in constraining the age of a new ice core from Roosevelt Island in Antarctica. The tephra record now shows the eruption responsible for the 1254 tephra is the largest known of any Holocene/Quaternary volcano in Antarctica and probably resulted in the formation of a 2 km wide caldera which defines the summit area of Rittmann volcano.

P 1.8 in Poster session 1: 25.06.2018, 14:00-

Tephra improves understanding of explosive eruption frequency and magmatic evolution at active volcanoes 1 2 1 BERGRÚN ARNA ÓLADÓTTIR , OLGEIR SIGMARSSON , GUÐRÚN LARSEN 1 Institute of Earth Sciences, University of Iceland 2 Institute of Earth Sciences, University of Iceland. Laboratoire Magmas et Volcans, CNRS and Université Clermont Auvergne, France Contact: [email protected]

Understanding of volcanoes, such as magma evolution, eruption history and their lifetime, is obtained through studies on volcanic products, both effusive and explosive. Gradually these products become covered with younger strata but as the lavas have less areal distribution they generally become buried under younger lavas making them difficult, and sometimes even impossible, to access. The tephra, on the other hand, becomes buried in soil, ice and other sediments (lake, marine) making it possible to study volcanic behaviour through time. Additionally, magma quenching during tephra formation forms a snapshot of the melt evolution through an eruption and, potentially over a lifetime of a volcano.

In Iceland tephra is formed in ~80% of eruptions, making tephrostratigraphy an ideal tool to reconstruct eruptive history from: 1) written documentation (reach back ~900 yr), 2) glaciers (~800 yr), 3) terrestrial (~8 ka), 4) lake (~13 ka) and 5) marine environments (>50 ka). The main producers of basaltic tephra are volcanic systems on the Eastern Volcanic Zone, Grímsvötn, Bárðarbunga and Katla, partly covered by the ice caps Vatnajökull and 80

Mýrdalsjökull (the latter covers Katla volcano). Their subglacial central volcanoes have frequently erupted explosively during the Holocene and ages of the eruptions are obtained through both direct and relative dating of tephra e.g. by correlations of well-known marker layers such as the widespread silicic Hekla layers. Terrestrial tephra around the two ice caps show periodic volcanic activity during the last ~8000 years. Volcanoes beneath Vatnajökull are located close to the centre of the Iceland mantle plume and show maximum activity at 7- 5 ka and 2-1 ka with a lull in activity from 5-2 ka most likely caused by decrease in volcanic activity rather than environmental factors. The Katla volcano, farther away from the mantle plume, shows activity peaks from 8-7 ka and 4-2 ka with a lull from 7-4 ka. Eruption frequency estimated for Grímsvötn and Bárdarbunga volcanoes was highest 2-1 ka ago, with 140 and 80 basaltic eruptions, respectively, whereas Katla volcano had two peaks of estimated 60 eruptions in the periods 4-3 ka and 8-7 ka. The reason for different timing of maximum activity at volcanoes above or beside the mantle plume centre is still an open question but may be related to delay in volcanic response to magma generation at depth.

The three volcanic systems, Grímsvötn, Bárðarbunga and Katla, mainly produce basaltic tephra, easily identified based on major element concentration. Tephra series reaching back ~8000 years confirm well defined magma suites during the studied time, although significant magma differentiation is observed. In the case of Katla the compositional changes have been interpreted as a result of a changing magma plumbing system beneath the volcano and volume estimation of selected Katla tephra layers indicate a steady state behaviour of the volcano over at least ~3500 years.

Results from major and trace element analyses of Grímsvötn and Bárðarbunga tephra have revealed fundamental differences in basaltic magma composition. Both volcanoes produce basalts of tholeiitic composition with Bárðarbunga erupting, in general, olivine-normative tholeiite wheras the Grímsvötn products are quartz-normative tholeiite. The magma composition at both volcanic systems is controlled by crystal fractionation of clinopyroxene, plagioclase and olivine in different proportions. Crustal contamination is inferred from the most evolved basaltic composition. The Grímsvötn basalts form two compositional groups, named G-I and G-II where the G-I part of Grímsvötn magma is less, or not, affected by contamination.

The nature of tephra formation, its relatively wide distribution and good preservation potentials in different environments, therefore, make tephra an ideal data archive on volcanic behaviour. It contains e.g. information on magma generation, magma transfer through the crust from the melt source to the Earth‘s surface, source volcano, type of activity and erupted volume,increasing our understanding of volcanoes.

81

P 1.9 in Poster session 1: 25.06.2018, 14:00-

Catalogue of Icelandic Volcanoes - An open access web resource 1 2 3 BERGRÚN ARNA ÓLADÓTTIR , EVGENIA ILLYINSKAYA , GUÐRÚN LARSEN , MAGNÚS 3 4 4 5 GUÐMUNDSSON , KRISTÍN VOGFJORD , EMMANUEL PAGNEUX , BJÖRN ODDSSON , SARA 4 4 BARSOTTI , SIGRÚN KARLSDÓTTIR 1 Icelandic Meteorological Office, Reykjavík, Iceland and Institute of Earth Sciences, University of Iceland, Reykjavík, Iceland 2 School of Earth and Environment, University of Leeds, Leeds, United Kingdom 3 Institute of Earth Sciences, University of Iceland, Reykjavik, Iceland 4 Icelandic Meteorological Office, Reykjavik, Iceland 5 Department of Civil Protection and Emergency Management, National Commissioner of the Icelandic Police, Reykjavik, Iceland Contact: [email protected]

The Catalogue of Icelandic Volcanoes (CIV) is an open-access web resource intended to serve as an official source of information about volcanoes in Iceland for both public and decision makers (http://icelandicvolcanoes.is). It contains text and graphic information on all active volcanic systems in Iceland in a format that enables non-specialists to understand the volcanic activity status, as well as real-time data from monitoring systems. The CIV Data portal contains scientific data on all Icelandic eruptions since Eyjafjallajökull 2010 and is an unprecedented endeavour in making volcanological data open and easy to access.

Extensive research has taken place on Icelandic volcanism, and the results reported in numerous scientific papers and other publications. In 2010, the International Civil Aviation Organisation (ICAO) funded a three-year project to collate the current state of knowledge and create a comprehensive catalogue readily available to decision makers, stakeholders and the public. The work on the Catalogue began in 2011, further supported by the Icelandic government and the EU through the FP7 project FUTUREVOLC. CIV also forms a part of an integrated volcanic risk assessment project in Iceland GOSVÁ (commenced in 2012).

The CIV is built up of chapters with texts and various mapped information for each of the 32 volcanic systems in Iceland. The contributions are classified in three types: 1. Text and other material (including maps and tephra grain size data) on geological aspects and eruption history. This constitutes the bulk of the information presented in the catalogue. 2. Sub- chapters on current alert level and activity status for each volcanic system, updated automatically with information from the IMO monitoring network. 3. Sub-chapters on eruption scenarios, based on the eruption history.

This work is a collaboration of the Icelandic Meteorological Office (IMO), the Institute of Earth Sciences at the University of Iceland, and the Civil Protection Department of the National Commissioner of the Iceland Police, with contributions from a large number of specialists in Iceland and elsewhere.

82

P 1.10 in Poster session 1: 25.06.2018, 14:00-

Mid Holocene eruptions in Hekla volcano: the Hekla Ö, Hekla MÓ and Hekla DH tephra layers 1 1 1 DANÍEL FREYR JÓNSSON , ESTHER RUTH GUDMUNDSDÓTTIR , BERGRÚN ARNA ÓLADÓTTIR , 1 2 GUDRÚN LARSEN , OLGEIR SIGMARSSON 1 Institute of Earth Sciences, University of Iceland 2 Institute of Earth Sciences, University of Iceland and Laboratoire Magmas et Volcans, CNRS and Université Clermont Auvergne, France Contact: [email protected]

Understanding and knowledge of past volcanic activity and eruptive behaviour of volcanoes is crucial to predict their future activity. Hekla volcano being one of the most active volcano in Iceland is known for its explosive eruptions. Studies on prehistoric tephra have focused on the large plinian eruptions, namely Hekla 5, Hekla 4 and Hekla 3. Here, the aim is to improve the knowledge of other prehistoric eruptions and the volcanic history of Hekla by investigating mid Holocene tephra layers, i.e. between the Hekla 5 and Hekla 4. The main focus is on three tephra layers in particular, the Hekla Ö (6060 cal yr BP), Hekla MÓ (~6060 cal yr BP) and Hekla DH (6600 cal yr BP). The stratigraphical position of Hekla MÓ is directly below Hekla Ö in the investigated soil sections, indicating a similar age of the two layers.

The Hekla DH, Hekla MÓ and Hekla Ö tephra layers have been described, mapped and their composition analyzed in several soil sections proximal to Hekla proper. The magma composition of these three layers range from rhyolite through andesite and basaltic-andesite to basalt. The Hekla DH and Hekla MÓ represent the earliest confirmed eruptions of intermediate magma from Hekla, which subsequently has become the dominant product of the volcano. The basalts (SiO2~46-47%) observed in these three layers consists of two types; one with TiO2<3 wt% and Al2O3>15 wt% and the other with TiO2>3 wt% and Al2O3<14 wt% for a MgO concentration of >6 wt% and <6 wt% respectively.

New isopach maps are compiled for all three tephra layers. Mapping the dispersal of the Hekla DH tephra has confirmed a source in the Valagjá area, in the northern part of the Hekla system. With the chemical dataset obtained in this study, a relationship between Hekla Ö and a distal Hekla tephra in NW-Iceland is suggested. Consequently, the Hekla Ö tephra possibly covers as much as 80% of terrestrial Iceland.

P 1.11 in Poster session 1: 25.06.2018, 14:00-

Event history of active faults and slope failures based on tephra stratigraphy - An example of the 2016 Kumamoto earthquake - 1 1 2 3 4 MASAYUKI TORII , TOSHIAKI HASENAKA , SHINJI TODA , KEN-ICHI NISHIYAMA , MITSURU OKUNO 1 Kumamoto University, Japan 2 Tohoku University, Japan 3 Tokushima University, Japan 4 Fukuoka University, Japan Contact: [email protected]

The 2016 Kumamoto earthquake (Mjma = 7.3) occurred on April 16, 2016 in Kumamoto Prefecture, SW Japan. The 30 km-long surface rupture associated with the earthquake appeared along the previously mapped active Futagawa fault. The earthquake gave damages to the cities of Mifune, Kumamoto, Mashiki, Nishihara and Minami-Aso along Furtagawa fault, from the Kumamoto plain, to inside Aso Caldera, with destruction of more than 8,000 buildings. Numerous slope failures affected infrastructure in and around Aso caldera. Although there were regional differences of the vibration characteristics of the earthquake, the main differences were probably caused by geological characteristics. The 83 caldera wall is composed of the volcanic rocks of the pre-caldera activity, whereas the area inside the caldera is composed of lavas and thick fallout tephras from the post-caldera volcanism. To clarify the mechanism of slope failures in volcanic regions, it is necessary to investigate the fault activity and collapse history. Since Aso area is covered with the tephras of the post-caldera volcanic activities, these tephras can be used as key layers to clarify the history of earthquake events. Miyabuchi (2009) and others described the stratigraphy of tephra layers originates from Aso post-caldera volcanism , mainly at eastern part of caldera, because they distribute to the east side of the vents. In the western part of caldera, which was damaged by the Kumamoto earthquake, accurate tephra stratigraphy to establish history of fault activity was insufficient. Therefore, we conducted a geological survey to establish tephra stratigraphy in the western part of Aso caldera. Many new outcrops have appearedas the result of field work and drilling survey in this area for the restoration of the afflicted area, and a lot of information could be obtained. We recognized a number of new tephra layers younger than 50 ka. We established accurate stratigraphy of tephras using petrological features and radiocarbon ages. Our findings include: (1) the analysis of vertical displacement of tephras along fault in research trenches revealed the estimated recurrence rate of the activity of the Futagawa Fault in the Aso area is about 2400 years (Toda et al., 2018). (2) collapsed structure of Nagano volcano and overlying tephra layers revealed the tephra layers have been broken down in multiple times, and Nagano volcano is a source volcano of Tateno lava flow. As described above, newly recognized tephra layers are used for active fault analysis and determination of the slope collapse age.

P 1.12 in Poster session 1: 25.06.2018, 14:00-

A Holocene cryptotephra record from north-western Canada with more than 35 distal tephra falls since 10,500 cal yr BP 1 1 LAUREN DAVIES , DUANE FROESE 1 Department of Earth and Atmospheric Sciences, University of Alberta Contact: [email protected]

Development of a cryptotephra framework in North America is in its nascent stages with a few Holocene and latest Pleistocene records known from eastern North America, but a general paucity of records from more proximal (but still cryptotephra) locales. In order to address this problem, we sampled a near-complete Holocene soligenic peatland in the north- central Yukon, Canada. This site records continuous accumulation since ~10,500 cal yr BP in ~5 m of ombotrophic peat. The only major clastic inputs to the peatland record are from loess and, more commonly, distal tephra. We develop a a distal tephrostratigraphy for northwestern Canada from 29 peaks representing at least 35 eruptions. Each of these distinct geochemical populations is defined by at least 10 EPMA analyses of major element geochemistry. Geochemical characterisation indicates that these layers are primarily produced from the Aleutians and south-eastern Alaska, although two ultra-distal tephra in the early Holocene are correlated with large caldera forming eruptions from Kamchatka (KO) and the Kurile Islands (TR(Zv)).

This work demonstrates that cryptotephra in north-western North America have significant potential to support a wide range of research projects. This record is presented as a key contribution to the development of a regional tephrostratigraphic framework within North America by providing a thorough characterisation of Holocene cryptotephra transported in to northwestern Canada from western sources.

P 1.13 in Poster session 1: 25.06.2018, 14:00- 84

Glass geochemical variability of historic Mount St. Helens eruptions and insights into eruption characteristics 1 2 BRITTA JENSEN , FOO ZHEN HUI 1 Earth and Atmospheric Sciences, University of Alberta 2 Asian School of the Environment, Nanyang Technological University Contact: [email protected]

The 19th and 20th century eruptions from Mount St. Helens provide important chronostratigraphic markers for regional paleoenvironmental studies in a timeframe where radiocarbon dates are unreliable and tephras are poorly geochemically characterized. The series of mid-19th century eruptions are particularly poorly understood, with most of our knowledge limited to sparse historical descriptions of the events. Here we present the glass geochemistry of two previously identified proximal tephra samples from the 1980 Mt. St. Helens (MSH) eruption and Layer T (AD 1800), as well as a new tephra that we argue represents the AD 1842 MSH eruption. Our results indicate that the tephras ejected during these three eruption events from Mount St. Helens within a timeframe of ~200 years have distinct glass geochemical characteristics that can be used to identify distal deposits. Mullineaux (1996) first reported the AD 1842 ash and suggested that this event represented a small phreatic eruption(s) that only ejected particles of pre-existing rock. Our results show that this is not the case with the presence of mineral-poor fine pumice that is geochemically distinct from the other eruptions and the glass matrix of the lithic dome-derived material that is also present in the tephra. This suggests that this event did involve the eruption of juvenile material, potentially elevating the importance of this event that deposited over a centimeter of ash over 100 km SE of MSH at The Dalles, Oregon.

P 1.14 in Poster session 1: 25.06.2018, 14:00-

Wizards’ Floods and classical tephrochronology 1 1 2 ANDREW DUGMORE , ANTHONY NEWTON , EMILY LETHBRIDGE 1 School of GeoSciences, University of Edinburgh 2 Árni Magnússon Institute for Icelandic Research, University of Iceland Contact: [email protected]

Using classical tephrochronology, we explore the circumstances under which early textual sources record some major geomorphological changes in the landscape, but ignore others. We focus on a case study from medieval Iceland and firstly use tephrochronology tied to the Greenland ice core record to explore precise links between the geomorphological records of extensive landscape change around the glacier Sólheimajökull and floods recorded in both the Icelandic Book of Settlement and later folk tales. We note that at the same time, other floods from beneath the neighbouring icecap Eyjafjallajökull that were associated with a flank fissure eruption visible over a wide areas of south-west Iceland, are not recorded in same sources. We suggest that this is due to their contrasting socio-political setting and in doing so we draw out wider implications for both environmental memories and the theoretical and methodological challenges to 21st century cross-disciplinary research involving classical tephrochronology.

85

P 1.15 in Poster session 1: 25.06.2018, 14:00-

The potential of tephrochronology for linking climate, environmental change and human colonisation of the South Pacific. 1 1 1 ANNA BOURNE , PETER LANGDON , DAVID SEAR 1 Geography and Environment, University of Southampton, Southampton, UK Contact: [email protected]

The archipelagos of Polynesia (some 7,500 islands) in the South Pacific were the last habitable places on earth colonised by prehistoric humans. However, the timing of this colonisation has been poorly resolved across many islands, with dates varying by up to 1000 years, precluding understanding of the interplay between human, ecological and climate impacts on these pristine ecosystems. The late colonisation of many Pacific islands makes them, theoretically, the ideal location to study natural environments prior to, and subsequent to the arrival of humans, but conversely there is a paucity of palaeoenvironmental research. Very little high quality palaeoenvironmental data spanning this period exists for the South Pacific. In order to begin to answer questions about the interplay between prehistoric human migration, the climate and environment, archaeological and palaeoenvironmental records need to be well dated and independently synchronised, something which is not currently possible. Existing chronologies are based on radiocarbon dating which is challenging in some of these sites especially where plant macrofossils are not available.

This poster examines how volcanic ash can provide a chronological framework for dealing with these questions. Initial cryptotephra results from Lake Lanoto’o, Samoa are presented as the first steps in the generation of a tephrochronological framework for the South Pacific islands. Future directions for the work will be discussed.

P 1.16 in Poster session 1: 25.06.2018, 14:00-

Radiocarbon chronology of the post-caldera volcanoes of Buyan-Bratan caldera in the island of Bali, Indonesia 1 2 2 3 MITSURU OKUNO , AGUNG HARIJOKO , I WAYAN WARMADA , TOSHIO NAKAMURA , TETSUO 4 KOBAYASHI 1 Department of Earth System Science, Fukuoka University 2 Department of Geological Engineering, Gadjah Mada University 3 Institute for Space-Earth Environmental Research, Nagoya University 4 Emeritus Professor, Kagoshima University Contact: [email protected]

We conducted field survey and radiocarbon dating to establish eruptive history of the post- caldera volcanoes (Lesung, Tapak, Sengayang, Pohen and Adeng) of Buyan-Bratan caldera in Bali Island, Indonesia. Tapak volcano has three craters aligned from north to south, it can be divided into each of the edifice. A lava dividing the Tamblingan and Buyan lakes flows down to the northwest from the central crater. This lava also covers the tip of the lava flow from Lesung volcano. Therefore, this is a product of the latest eruption in the post-caldera volcanoes. Lesung volcano also has two craters, and specific gully developing on a pyroclastic cone from north to western slope. Lava from the south crater flows down to the western flank beyond the caldera rim. Another lava distributed in the east from the south also surrounds Sengayang and Pohen volcanoes. Adeng volcano is surrounded by lava and/or pyroclastic deposits from Pohen volcano. Based on these topographic relationships, Sengayang and Adeng volcanoes are the oldest in the post-caldera volcanoes, and then Pohen, Lesung, and Tapak volcanoes have been formed up to the present. Coarse-grained scoria falls around this area are intercalated with two foreign tephras, the Samalas AD 1257 tephra from Lombok Island and the Penelokan tephra (ca. 5.5 kBP) from Batur caldera. At northern slope of Buyan-Bratan caldera, we obtained four AMS radiocarbon dates. They 86 indicate that the last two scoria eruptions occurred at ca. 1 and 2.5 kBP, respectively.The source of these scoria falls are estimated to be Tapak or Lesung volcanoes. It indicates that two volcanoes erupted in the Holocene period.

P 1.17 in Poster session 1: 25.06.2018, 14:00-

The Campanian Ignimbrite tephra layer: How far north does it reach? 1 2 3 4 5 YUNUS BAYKAL , ULRICH HAMBACH , IGOR OBREHT , CHRISTIAN ZEEDEN , DANIEL VERES , 6 7 7 8 ZORAN PERIC , PHILIPP SCHULTE , FRANK LEHMKUHL , SLOBODAN B. MARKOVIC 1 Chair of Geomorphology, University of Bayreuth, 95440 Bayreuth, Germany 2 BayCEER and Chair of Geomorphology, University of Bayreuth, 95440 Bayreuth, Germany 3 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, D-28359 Bremen, Germany 4 IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universites, UPMC Univ Paris 06, Univ Lille, 75014 Paris, France 5 Institue of Speleology, Romanian Academy, Clinicilor 5, 400006 Cluj-Napoca, Romania 6 Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, 55128 Mainz, Germany 7 Department of Geography, RWTH Aachen University, Templergraben 55, 52056 Aachen, Germany 8 Chair of Physical Geography, Faculty of Science and Mathematics, University of Novi Sad, Trg Dositeja Obradovica 3, 21000 Novi Sad, Serbia Contact: [email protected]

The Campanian Ignimbrite (CI) super-eruption of the Phlegrean Fields (Italy) was the most explosive volcanic event in the Mediterranean area during the Late Pleistocene, concerning both the eruption magnitude and volume of volcanic ejecta. The eruption is dated to 39-40 ka and coincides with the onset of Heinrich Event 4 (HE4), an extremely cold and dry climatic phase. The CI tephra was widely distributed from its source vent in southern Italy throughout western Eurasia as far east as the Russian plain (2200 km distance to source) and southwards to the north African coast. Therefore, a positive feedback mechanism affecting not only European but global climatic dynamics is very likely.

Besides the potential to evaluate the role of volcanism on climate forcing, the CI event may provide key information to understand evolutionary processes of the Early Upper Palaeolithic since its timing coincides with the arrival of anatomically modern humans (AMH) into Europe. Furthermore, the CI tephra serves as a powerful chronostratigraphic marker horizon to synchronize records of natural archives during Marine Isotope Stage (MIS) 3.

The present case study focusses on a high-resolution MIS 3 multi-proxy record from the Titel Plateau (Vojvodina, Serbia) situated in the Carpathian Basin at the junction of Tisza and Danube. The data was obtained using a multi-disciplinary approach (colour, grain-size, environmental magnetic and geochemical (EDPXRF) properties) on a continuously sampled outcrop section. The section was correlatively dated based on the age model for Serbian loess-palaeosol sequences (LPS) (Basarin et al., 2014) and on the unpublished age model from Urluia (Dobrogea, Romania). Furthermore, numerical age constraints can be derived from the OSL dated Titel core (TLP-1) that shows a nearly congruent grain-size signal (Peric et al., 2018). Selected samples were analysed for volcanic glass shards using optical microscope and microprobe analyses. So far, single-grain, wavelength-dispersive electron microprobe analysis for investigation of glass shard major oxide chemical composition failed.

Rapid palaeoclimate changes during MIS 3 are well documented in the high-resolution multi- proxy data from Titel. Colour data as well as rock magnetic and geochemical properties show a corresponding, distinct pattern which is expected to be driven by in-situ weathering and pedogenesis. In between two embryonic soil horizons, the grain-size distribution shows a striking peak in coarse fractions (< 200 µm) that corresponds to the residual proxies and can be assigned as HE4. Volcanic glass shards were found in these samples and, given their 87 chronostratigraphic position, very likely linked to the CI event. Strong, weathering and redeposition-based alteration of the grains inhibited identification by geochemical properties, so far.

Our finding of the CI tephra in the southern Carpathian Basin contributes to the ongoing debate about the eruption magnitude and volume of volcanic particles ejected during the CI event. In concordance to previous studies (Fitzsimmons et al. 2013, Marti et al., 2016) the occurrence of CI tephra particles at Titel Plateau in the Carpathian Basin supports the need to re-evaluate magnitude of the eruption and ash volume ejected by the eruption. Furthermore, the spatial distribution of the distal ashfall, in particular the northern border, needs to be reassessed in order to evaluate its impact on regional climates, local ecosystems and the dispersal of AMH throughout Europe. A line from the Adriatic Sea (Susak island, Wacha et al. 2011) along the Titel-Plateau, the western beginning (site near Kisijelov) and eastern end of the Danube Iron Gates (Tabula Traiana Cave, Lowe et al., 2012) provides a minimum northern extend of the CI-tephra dispersal in the Carpathian Basin. In order to validate this minimum northern extend, further research tracking CI-tephra occurrences northwards is needed.

References Basarin, B., Buggle, B., Hambach, U., Marković, S. B., Dhand, K. O. H., Kovačević, A., Stevens, T., Zhengtang, G. & Lukić, T. (2014). Time-scale and astronomical forcing of Serbian loess–paleosol sequences. Global and Planetary Change, 122, 89-106. Fitzsimmons, K. E., Hambach, U., Veres, D., & Iovita, R. (2013). The Campanian Ignimbrite eruption: new data on volcanic ash dispersal and its potential impact on human evolution. PLoS One, 8(6), e65839. Lowe, J., Barton, N., Blockley, S., Ramsey, C. B., Cullen, V. L., Davies, W., Lane, C. S., Lee, S., Lewis, M., MacLeod, A., Menzies M., Müller, W., Pollard, M., Price, C., Roberts, A. P., Rohling, E. J., Satow, C., Smith, V. C., Stringer, C. B., Tomlinson, E. L., White, D., Albert, P., Arienzo, I., Barker, G., Borić, D., Carandente, A., Civetta, L., Ferrier, C., Guadelli, J., Karkanas, P., Koumouzelis, M., Müller, U. C., Orsi, G., Pross, J., Rosi, M., Shalamanov-Korobar, L., Sirakov, N & Tzedakis, P. C. (2012). Volcanic ash layers illuminate the resilience of Neanderthals and early modern humans to natural hazards. Proceedings of the National Academy of Sciences, 109(34), 13532-13537. Marti, A., Folch, A., Costa, A., & Engwell, S. (2016). Reconstructing the plinian and co-ignimbrite sources of large volcanic eruptions: A novel approach for the Campanian Ignimbrite. Scientific reports, 6, 21220. Perić, Z., Adolphi, E. L., Stevens, T., Újvári, G., Zeeden, C., Buylaert, J. P., Marković, S. B., Hambach, U., Fischer, P., Schmidt, C., Schulte, P., Huayu, L., Shuangwen, Y., Lehmkuhl, F., Obreht, I., Veres, D., Thiel, C., Frechen, M., Jain, M., Vött, A., Zöller, L. & Gavrilov, M. B. (2018). Quartz OSL dating of late quaternary Chinese and Serbian loess: A cross Eurasian comparison of dust mass accumulation rates. Quaternary International. Wacha, L., Pavlaković, S. M., Novothny, Á., Crnjaković, M., & Frechen, M. (2011). Luminescence dating of Upper Pleistocene loess from the Island of Susak in Croatia. Quaternary International, 234(1- 2), 50-61. Zeeden, C., Hambach, U., Veres, D., Fitzsimmons, K., Obreht, I., Bösken, J., & Lehmkuhl, F. (2016). Millennial scale climate oscillations recorded in the Lower Danube loess over the last glacial period. Palaeogeography, Palaeoclimatology, Palaeoecology.

88

Poster session 2

P 2.1 in Poster session 2: 27.06.2018, 14:00-

Post-caldera tephrostratigraphic framework of Aso Volcano, southwestern Japan 1 YASUO MIYABUCHI 1 Faculty of Advanced Science and Technology, Kumamoto University Contact: [email protected]

Aso Volcano, which is located in central Kyushu, southwestern Japan, is one of the most beautiful caldera volcanoes in the world. During 270 to 90 ka, gigantic caldera-forming eruptions of andesitic to rhyolitic magma occurred four times in the volcanic field. Post- caldera central cones situated within Aso caldera were initiated soon after the formation of the youngest caldera (90 ka). The cones have not only produced local lava flows but also voluminous tephra layers that fell regionally, far beyond the caldera. The stratigraphy and chronology of the tephra layers are evaluated through study of the thick tephra sequence preserved mainly atop the Aso pyroclastic-flow plateau around the caldera in order to reconstruct the eruptive history of the post-caldera central cones during the past 90,000 years.

Most of the tephra layers distributed in and around Aso caldera are andesitic to basaltic- andesitic scoria-fall and ash-fall deposits. Their stratigraphy is very complicated because it is difficult to distinguish between scoria-fall layers in the field. However, dacitic to rhyolitic pumice-fall deposits from some central cones interbedded within the tephra layers are very useful for correlation of stratigraphic units at disparate localities. Therefore, the pumice-fall deposits are used to correlate and reconstruct the tephrostratigraphy and eruptive history of the post-caldera central cones during the past 90,000 years.

Thirty-six pumice-fall deposits were identified, including fifteen major key beds. In ascending order they are Nojiri pumice (NjP), Ogashiwa pumice (OgP), Yamasaki pumices 5 to 1 (YmP5-YmP1), Sasakura pumices 2 (SsP2) and 1 (SsP1), Aso central cone pumices 6 to 3 (ACP6-ACP3), Kusasenrigahama pumice (Kpfa), and Aso central cone pumice 1 (ACP1). Phenocrystic minerals of most pumices are plagioclase, ortho- and clinopyroxene and titanomagnetite, but NjP, ACP5, ACP3, and ACP1 include biotite, and NjP and SsP2 contain hornblende phenocrysts. ACP4 and ACP3 were correlated with the dacitic Tateno lava and the rhyolitic Takanoobane lava (51 ka; K-Ar age) respectively, distributed in the western part of the central cones. Moreover, several scoria-fall deposits, the Yamasaki scoria 20 to 15 (YmS20-YmS15), Kishimadake scoria (KsS), Ojodake scoria (OjS) and Nakadake N2 scoria (N2S), are observed around the caldera.

On the basis of 14C ages from some pumice-fall layers and K-Ar ages of the Takanoobane lava (=ACP3) and the Aso-4 pyroclastic-flow deposit, eruption ages for other pumice layers are stratigraphically estimated. Thus, eruption ages for the fifteen major pumice layers are estimated as follows: NjP (84 ka), OgP (79 ka), YmP5-YmP1 (68-67 ka), SsP2 (64 ka), SsP1 (64 ka), ACP6 (60 ka), ACP5 (55 ka), ACP4 (51 ka), ACP3 (51 ka), Kpfa (30 ka), YmS20- YmS15 (22-21 ka), ACP1 (4.1 ka), KsS (4 ka), OjS (3.6 ka) and N2S (1.5 ka). During the past 90,000 years post-caldera central cones produced pumice-fall deposits at an interval of about 2,500 years. Although bulk volumes of two silicic eruptions producing NjP and Kpfa were on the order of 1 km3 (VEI 5), others were smaller than 0.1 km3. Plinian eruptions producing ACP4 and ACP3 were followed by compositionally homogeneous lava flows. The catastrophic 30 ka eruption at Kusasenrigahama crater was initiated by the dacitic Sawatsuno lava flow and produced the largest plinian pumice-fall deposit (Kpfa: 2.2 km3). However, almost all the vents that produced pumices older than 30 ka have not been identified, and are probably buried by the younger volcanic products from the present central cones. 89

Total tephra volume in the past 90,000 years is estimated at about 18.1 km3 (dense rock equivalent: DRE), whereas total volume for edifices of the post-caldera central cones is calculated at about 112 km3, which is six times greater than the former. Therefore, the average magma discharge rate during the post-caldera stage of Aso Volcano is estimated at about 1.5 km3/ky, which is similar to rates for other Quaternary volcanoes in Japan.

P 2.2 in Poster session 2: 27.06.2018, 14:00-

Luminescence age constraints on the Pleistocene-Holocene transition recorded in loess sequences across SE Europe 1 2 3 4 DANIELA CONSTANTIN , DANIEL VERES , CRISTIAN PANAIOTU , VALENTINA ANECHITEI-DEACU , 4 4 4 STEFANA MADALINA GROZA , ROBERT CSABA BEGY , SZABOLCS KELEMEN , JAN-PIETER 5 6 7 8 BUYLAERT , ULRICH HAMBACH , SLOBODAN MARKOVIĆ , NATALIA GERASIMENKO , ALIDA TIMAR- 9 GABOR 1 Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University 2 Institute of Speleology, Romanian Academy 3 Faculty of Physics, University of Bucharest 4 Faculty of Environmental Sciences and Engineering, Babeş-Bolyai University 5 Center for Nuclear Technologies, Technical University of Denmark and Nordic Laboratory for Luminescence Dating, Department of Geoscience, Aarhus University 6 BayCEER & Chair of Geomorphology, University of Bayreuth 7 Laboratory for Paleoenvironmental Reconstruction, Faculty of Sciences, University of Novi Sad 8 Earth Sciences and Geomorphology Department, Taras Shevchenko National University of Kyiv 9 Interdisciplinary Research Institute in Bio-Nano-Sciences and Faculty of Environmental Sciences and Engineering, Babeş-Bolyai University Contact: [email protected]

Here we investigate the timing of the last glacial loess (L1) - Holocene soil (S0) transition recorded in loess-paleosol sequences from SE Europe (Ukraine, Romania, Serbia) by applying comparative luminescence dating techniques on quartz and feldspars. Equivalent dose measurements were carried out using the single-aliquot regenerative-dose (SAR) protocol on silt (4-11 µm) and sand-sized (63-90 µm and coarser fraction when available) quartz. Feldspar infrared stimulated luminescence (IRSL) emitted by 4-11 µm polymineral grains was measured using the post IR-IRSL290 technique.

The paleoenvironmental transition from the last glacial loess to the current interglacial soil was characterized using the magnetic susceptibility and its frequency dependence. SAR- OSL dating of 4-11 µm, 63-90 µm and 90-125 µm quartz provided consistent ages in the loess-paleosol sites investigated, while the post-IR IRSL290 protocol proved unreliable for accurate dating of such young samples. Based on these ages, the threshold of the magnetic signal enhancement, and thus the onset of soil formation have been placed around 16.6±1.1 ka at Roxolany (Ukraine), 13.5±0.9 ka at Mošorin (Serbia) and between 17.6±1.4 ka and 12.4±1.0 ka at Râmnicul Sărat (Romania). The trend observed in the magnetic parameters reflects the intensity of pedogenesis induced by regional climate amelioration during the Late Glacial, but the onset of magnetic susceptibility enhancement precedes the stratigraphic boundary of Pleistocene-Holocene dated at 11.7 ka in ice core records.

Thus, magnetic susceptibility indicates a gradual increase in pedogenesis after Termination 1 (~ 17 ka in the North Atlantic) at the sampling sites. Based on current data, it is not possible to define a threshold of change synchronous for all sections. However, the trend in the magnetic susceptibility data closely reflects the gradual transition from Last Glacial Maximum (LGM) towards the Holocene, with the onset of humus accumulation (A1 horizon) possibly linked to the prevalence of full interglacial conditions. 90

P 2.3 in Poster session 2: 27.06.2018, 14:00-

Independent chronostratigraphic markers and varve chronology in the Lateglacial palaeoenvironmental record of Lake Hämelsee, N-Germany 1 2 3 4 5 ARITINA HALIUC , INA NEUGEBAUER , CHRISTINE LANE , STEFAN ENGELS , GWYDION JONES , 6 7 DIRK SACHSE , ACHIM BRAUER 1 Research Institute of the University of Bucharest, University of Bucharest, 6-46 Bd. M. Kogalniceanu, 5th District, 050107, Bucharest, Romania 2 University of Geneva, Department of Earth Sciences, Rue des Maraichers 13, CH-1205 Geneva, Switzerland 3 University of Cambridge, Department of Geography, Downing Place, Cambridge, CB2 3EN, UK 4 School of Geography, Birkbeck University of London, UK 5 Swansea University, Department of Geography, College of Science, Singleton Park, Swansea, SA2 8PP, UK 6 GFZ German Research Centre for Geosciences, Section 5.1 Geomorphology, Telegrafenberg, 14473, Potsdam, Germany 7 GFZ German Research Centre for Geosciences, Section 5.2 Climate Dynamics and Landscape Evolution, Telegrafenberg, 14473, Potsdam, Germany Contact: [email protected]

It has been shown that climate is changing at unexpected rates not only at millennial but also at sub- to multi-decadal scales that can even occur at less than a human perspective. The increasing abundance of information about abrupt climate change and environmental responses recorded in natural archives have highlighted that chronology is a key issue for adequately using the multi-proxy data sets. In this context, we need reliable information about the timing of these past changes such as the transition time elapsed from one climatic state to the other, the time needed for changing climatic conditions to imprint an environmental response. This will enhance our understanding about the mechanism, periodicities of climate change and will further help to constrain the uncertainties of simulation models and to assist the improvement of future predictions.

Here we present the results for the partly laminated Lateglacial sequence from a new core collected in 2013 from Lake Hämelsee (north-west Germany). Previously, Lake Hämelsee was subjected to a suite of multi-disciplinary studies including detailed sedimentological, geochemical and palynological analysis (Kleinnman, Merkt, Muller, 2001; Litt and Stebich, 1999; Merkt and Müller, 1999) which showed important environmental and climatic changes over Lateglacial and attested lake potential for high-resolution investigations. In 2013, the lake became part of the interdisciplinary research project INTIMATE (Integrating Ice Core, Marine and Terrestrial records) as a key site to investigate possible linkages between terrestrial, marine and ice records.

In the present study, we present the Lateglacial-Early Holocene sequence from Lake Hämelsee and focus our discussion to the proxy response to environmental and climatic changes over the laminated interval which covers the Allerød and Allerød/Younger Dryas transition. The investigated record is anchored to the absolute timescale through five tephra layers (Laacher See, Vedde Ash, Ulmener Maar, Askja-S and Saksunarvatn tephras). Our investigation is based on more sophisticated methodological approaches than previously used as we combine micro-facies and micro-XRF element scanning, varve and tephra chronology in order to identify important changes in the depositional environment.

A floating 825 ± 5 years’ varve chronology spanning from 13,459 ± 45 to 12,635 ± 45 vyrs BP (varve years before present) was established and anchored to the absolute time scale using the Laacher See Tephra (LST). A first gradual micro-facies change characterized by a shift from siderite-organic to calcite-organic varves takes place already ca. 80 earlier than the Younger Dryas onset, starting at 12,750 vyrs BP. A complete facies change, from calcite- organic varves to clastic-organic varves, takes place at 12,669 ± 45 vyrs BP characterized by 91 an increase in clay layer frequency and thickness. It reflects a pronounced and rapid sedimentological response to colder climatic conditions at the Allerød – Younger Dryas transition.

The presence of the Laacher See Tephra (12,880 vyrs B.P.) provides an excellent time- control and allows us to compare the signal inferred in sedimentological and geochemical proxies over the Allerød/Younger Dryas with the response of other terrestrial records from western and north-eastern Germany – Lake Meerfelder Maar, (Brauer et al., 2008) and Paleolake Rehwiese (Neugebauer et al., 2012). Our multi-proxy investigation demonstrates that Lake Haemelsee is a key site for Lateglacial climate reconstruction in central Europe.

References Brauer, A., Haug, G.H., Dulski, P., Sigman, D.M., Negendank, J.F.W., 2008. An abrupt wind shift in western Europe at the onset of the Younger Dryas cold period. Nat. Geosci. 1, 520–523. Kleinnman, A., Merkt, J., Müller, H., 2001. Rapid short term variations and response of proxies during the older Holocene. Terra Nostra 3, 112–114. Litt, T., Stebich, M., 1999. Bio- and chronostratigraphy of the lateglacial in the Eifel region, Germany. Quat. Int. 61, 5–16. Merkt, J., Müller, H., 1999. Varve chronology and palynology of the Lateglacial in Northwest Germany from lacustrine sediments of Hamelsee in Lower Saxony. Quat. Int. 61, 41–59. Neugebauer, I., Brauer, A., Dräger, N., Dulski, P., Wulf, S., Plessen, B., Mingram, J., Herzschuh, U., Brande, A., 2012. A Younger Dryas varve chronology from the Rehwiese palaeolake record in NE- Germany. Quat. Sci. Rev. 36, 91–102.

P 2.4 in Poster session 2: 27.06.2018, 14:00-

Zircon in tephra as a novel tool to decrypt geologic and archaeological archives: a case study from Central America 1 1 1 ALEJANDRO CISNEROS DE LEÓN , JULIE CHRISTIN SCHINDLBECK , AXEL K. SCHMITT , STEFFEN 2 KUTTEROLF 1 Institute of Earth Sciences, University of Heidelberg 2 GEOMAR Helmholtz Centre for Ocean Research Kiel Contact: [email protected]

Highly explosive and potentially caldera-forming silicic eruptions rank among the most violent geologic events on Earth. In the geologic record widespread tephra deposits form important marker horizons that permit dating of climate archives and key events in Earth’s history. On more recent geologic timescales, these deposits have also provided materials that are relevant to reconstruct human evolution and history. Although distributions of distal ash can be reasonably well constrained in large solitary systems (e.g., Yellowstone caldera, USA), this becomes complex in most arc settings, and especially in the highly active Central American Volcanic Arc where identification and allocation of distal tephra to individual eruptions and eruption centers is much more challenging, since chains of calderas have produced tephra deposition patterns that closely overlap in time, space, and composition. Because zircon is a common and often early-crystallizing phase in silicic systems, pyroclastic eruptions also widely distribute zircon across extensive areas where it can be recovered from ash deposits. Moreover, it is inert during weathering and diagenesis. This offers the potential to use zircon in tephra identification and dating where other compositional fingerprints are insufficiently discriminant.

Intensive work during the last decades established a Central American tephrostratigraphic framework where ages and stratigraphic relations are well constrained for the younger eruptions through studies of proximal outcrops and marine and lacustrine ash layers. There are, however, problematic correlations where conventional chemical fingerprinting remains 92 ambiguous, such as the difficulty of distinguishing Ilopango Terra Blanca tephras (TBJ, TB2, TB3, and TB4). Similar demand for better correlation tools exists for reliably distinguishing L- Fall Tephra (LFT) and E-Fall Tephra (EFT) from Amatitlán, which is not a problem where proximal units crop out in a completely preserved sequence, or within a well-constrained age model, but very challenging when they are distal and only isolated ash layers are exposed. For the purpose of further developing zircon as a tool to identify tephra, we are investigating the voluminous tephra deposits from four calderas in the Central American Volcanic Arc CAVA (Atitlán and Amatitlán in Guatemala; Coatepeque and Ilopango in El Salvador) that were potentially used as primary resources for temper in Maya pottery. To constrain the timing of zircon crystallization (which also provides a maximum depositional age for the tephra) we are applying 238U-230Th and U-Pb dating of zircon combined with trace element and stable isotope analysis as proof of concept that zircon is not only extremely useful in unraveling deep magmatic processes, but also as a powerful tool in deciphering and distinguishing tephra records over arc-wide spatial dimensions.

P 2.5 in Poster session 2: 27.06.2018, 14:00-

A new record of late Holocene (crypto)tephras clarifies timing of early Polynesian impact in northern New Zealand 1 2 3 4 MARIA GEHRELS , REWI NEWNHAM , DAVID LOWE , PAUL AUGUSTINUS 1 Environment Department, University of York, United Kingdom 2 School of Geography, Environment & Earth Sciences, Victoria University of Wellington, Wellington, New Zealand 3 School of Science, University of Waikato, Hamilton 3240, New Zealand 4 School of Environment, University of Auckland, Auckland, New Zealand Contact: [email protected]

The interpretation of pollen and other palaeoenvironmental records for human impacts in New Zealand prehistory has been hampered by a lack of high-resolution chronologies. In this paper we present the results of a detailed investigation of the visible and cryptotephra content of a late Holocene sequence of laminated lake sediment from Lake Pupuke, a maar lake in Auckland, northern North Island. The rhyolitic Kaharoa Tephra, erupted 1314 ± 12 AD (95% probability age range) from Mt Tarawera near Rotorua in central North Island, is preserved as a cryptotephra in the sediments. This tephra has not been previously found in the lake. Elsewhere in much of North Island it provides an important human settlement marker. For the first time the Kaharoa tephra is found together with the local basaltic Rangitoto tephras, Rangitoto-1 and Rangitoto-2 derived from Rangitoto volcano and aged c. 1400 AD and c. 1450 AD, respectively, adding critical chronological control to a key part of the record. The new pollen record shows an early phase of minor, localised forest clearance around the time of the Kaharoa tephra followed by a later, more extensive deforestation phase commencing at around the time of deposition of the Rangitoto tephras. Interestingly, this two-step pattern of early human impact in northern New Zealand is consistent with recent evidence for a ‘Little Ice Age’-like cooling phase commencing around the time of deposition of Rangitito tephras, and is consistent with archaeological evidence that the onset of harsher conditions impacted on pre-European Māori, causing a consolidation of populations and later environmental impact in northern New Zealand. This study demonstrates the effectiveness of cryptotephra together with visible tephra and radiocarbon dating to provide a high-resolution palaeoenvironmental reconstruction of early Polynesian/Māori impact in New Zealand.

93

P 2.6 in Poster session 2: 27.06.2018, 14:00-

CT and micro-CT scanning of liquefied tephra deposits in ~22,000-yr-old lake sediments, central Waikato region, New Zealand, and implications 1 1 2 2 REMEDY C. LOAME , DAVID J. LOWE , RICHARD E. JOHNSTON , ELIZABETH EVANS , ADRIAN 1 1 1 3 4 PITTARI , VICKI G. MOON , WILLEM P. DE LANGE , SIWAN M. DAVIES , CHRISTINA R. MAGILL , 5 6 7 MARCUS J. VANDERGOES , ANDREW B.H. REES , NIC ROSS 1 School of Science, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 2 College of Engineering, Swansea University, Swansea, Wales SA1 8EN, UK 3 Dept. of Geography, Swansea University, Singleton Park, Swansea, Wales SA2 8PP, UK 4 Department of Environmental Sciences, Macquarie University, St Leonards, NSW 2065, Australia 5 GNS Science, P.O. Box 30368, Lower Hutt 5040, New Zealand 6 School of Geography, Environment, and Earth Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand 7 Hamilton Radiology, Gate 1, Thackeray Street, Hamilton 3204, New Zealand Contact: [email protected]

Soft-sediment deformation structures (SSDS) can record evidence of the liquefaction and fluidisation of deposits. The use of X-ray computed tomography (CT) and micro-CT to scan unopened lake sediment cores offers a way to reconstruct the 3D volume of the disrupted tephra deposits within, capturing micro-structural features which may not be readily observable in a cut core or in photographs. Cores from lakes Ngaroto, Kainui, and Rotokauri in the Hamilton Basin in the Waikato region, North Island, New Zealand, formed ~21,000- 23,000 cal. yr BP, were scanned using a medical CT facility at a local private clinic in Hamilton (Hamilton Radiology). A segment of core from Lake Rotokauri was scanned using the micro-CT facility at Swansea University, UK. The reconstructed 3D volumes of the cores, examined using Fiji/ImageJ, revealed that multiple tephra deposits (but not the enclosing organic lake sediment) display SSDS, including injection structures, dish structures, voids, and disrupted internal bedding. The disrupted tephras so far identified are all rhyolitic in composition, fine grained (mainly fine to medium ash), and 2–5 cm in thickness. They include Tuhua (7.6 cal. ka), Mamaku (8.0 cal. ka), Waiohau (14.0 cal. ka), Rotorua (15.7 cal. ka), and Rerewhakaaitu (17.2 cal. ka). Many of the SSDS observed in CT images were partially or entirely obscured from view when the same cores were cut open, and some fragile structural features were destroyed in the process of core description. Descriptive and photographic data from prior lake-core records dating back to the 1980s indicated that three tephras were disrupted (Mamaku, Waiohau, Rotorua), but the CT imaging, including the micro-CT scans, of the new cores revealed that two more tephras (Tuhua, Rerewhakaaitu) were disrupted. The presence of non-disrupted tephra deposits in the cores gives temporal constraints to the SSDS which we infer represent palaeoliquefaction resulting from strong episodic seismic shaking near the lakes on one or more of ~25 newly-discovered hidden faults we have identified in the Hamilton Basin (see companion paper by Lowe et al.). The CT results, together with historical core records for a further nine lakes, suggest that at least five (palaeo)seismic events have occurred in the Hamilton Basin since c. 17,000 cal. yr BP. After c. 7600 cal. yr BP, most tephras in the lakes occur as thin layers only a few millimetres in thickness (or as cryptotephras), hence possible seismic events since then may not have been recorded in the form of SSDS because these tephras lack the required physical properties for liquefaction. The CT analysis of the SSDS in lake cores provides a new non- destructive tool for palaeoseismology, and the seismic activity can to be dated using tephrochronology.

94

P 2.7 in Poster session 2: 27.06.2018, 14:00-

Are numerical and statistical methods the panacea for correlating tephras or cryptotephras using compositional data? 1 2 3 4 DAVID J LOWE , NICK JG PEARCE , MURRAY A JORGENSEN , STEVE C KUEHN , CHRISTIAN A 5 6 TRYON , CHRIS L HAYWARD 1 School of Science (Earth Sciences), University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 2 Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB, UK 3 Department of Mathematical Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand 4 Department of Physical Science, Concord University, Athens WV 24712, USA 5 Department of Anthropology, Harvard University, Cambridge MA 02138, USA 6 School of GeoSciences, Grant Institute of Earth Science, University of Edinburgh, Edinburgh EH9 3JW, UK Contact: [email protected]

Correlations between tephra or cryptotephra deposits are testable hypotheses, subject to continual revision with expanded datasets. Consequently, the strongest correlations are those that show concordance between multiple independent datasets, including lithostratigraphic, palaeoenvironmental or archaeological data, chronological data, and mineralogical and geochemical evidence. In effect, prior correlations proposed on the basis of age equivalence are tested by examining potential correlatives suggested by mineralogical variations or by compositional variation within the glass or crystal/phenocryst phases of tephra deposits, or by dating materials associated with the tephras. Statistical methods provide a less subjective means of dealing with data pertaining to tephra components than alternative methods. They enable a better understanding of relationships among the data to be developed from multiple viewpoints, and help to quantify the degree of uncertainty in establishing correlations. In applying statistical methods to establish sample equivalence or difference, however, all methods have some degree of limitation. Furthermore, using statistical analysis of compositional data, it is easier to prove a difference between two samples than it is to prove they are the same. A two-stage approach to statistical correlation has been useful in recent times, the first stage being to identify the main data structure via simple but useful scatterplot matrices (bivariate plots) before undertaking statistical distance measures, SCs, hierarchical cluster analysis, and PCA. Some of these methods are also called machine learning. The second stage typically examines sample variance and the degree of compositional similarity. This stage may involve DFA, CVA, and analysis of variance (ANOVA) or MANOVA (or its two-sample special case, the Hotelling two-sample T2 test). Various transformations and scalings may be applied to compositional data prior to subjecting them to multivariate statistical procedures such as the calculation of distance matrices, hierarchical cluster analysis, and PCA (Fig. 1). Such transformations may make the assumption of multivariate normality more appropriate.

References Lowe, D.J., Pearce, N.J.G., Jorgensen, M.A., Kuehn, S.C., Tryon, C.A., Hayward, C.L. 2017. Correlating tephras and cryptotephras using glass compositional analyses and numerical and statistical methods: review and evaluation. Quaternary Science Reviews 175, 1-44. (https://doi.org/10.1016/j.quascirev.2017.08.003)

95

P 2.8 in Poster session 2: 27.06.2018, 14:00-

Isochron-informed Bayesian age modelling for tephras and cryototephras: application to mid-Holocene Tūhua tephra, northern New Zealand 1 2 2 3 4 DAVID J LOWE , ANDREW BH REES , REWI M NEWNHAM , ZOË J HAZELL , MARIA J GEHRELS , 5 5 DAN J CHARMAN , MATT J AMESBURY 1 School of Science (Earth Sciences), University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 2 School of Geography, Environment, and Earth Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand 3 Historic England, Fort Cumberland, Fort Cumberland Road, Portsmouth PO4 9LD, UK 4 Environment Department, University of York, York YO10 5DD, UK 5 Geography, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4SB, UK Contact: [email protected]

Tūhua tephra is a compositionally distinctive peralkaline rhyolitic eruptive derived from Mayor Island (also known as Tūhua) that lies in the Bay of Plenty ~30 km east of North Island, New Zealand. The tephra, containing common aegirine and diacritical glass (SiO2 ~73 wt%, Al2O3 ~10 wt%, Na2O ~6 wt%, K2O ~4 wt%, FeOt ~6 wt%), forms a unique chronostratigraphic marker bed for the Holocene of North Island and adjacent marine deposits to the east and southeast of the island. Deposition of Tūhua tephra coincided with the Holocene relative sea- level high-stand ~8100‒7200 cal. yr BP when present sea level was first attained. Deriving an accurate age for Tūhua tephra is therefore a priority for palaeoenvironmental applications as well as volcanology and palaeopedology. Ten dates have been obtained for the tephra, only one (Wk-77) from Mayor Island itself on ‘charcoal logs’ in the base of the pyroclastic flow associated with the Tūhua eruption (7172 ± 393 cal. yr BP) (95.4% probability range, PR). Bayesian age-modelling of the Kaipo bog sequence in eastern North Island using both Bacon (6577 ± 547 cal. yr BP) and OxCal (P_sequence, 6947 ± 150 cal. yr BP; Tau_boundary, 7027 ± 170 cal. yr BP, n = 10) (all 95.4% PR) generated contradictory and imprecise ages on Tūhua ranging from ~6600 to ~7100 cal. yr BP. Here we use a new approach to dating it by applying explicitly a key principle of tephrochronology to Bayesian age modelling: tephras are erupted and deposited effectively instantaneously forming isochrons so that a primary tephra or cryptotephra has an identical age everywhere it occurs. We therefore modelled 54 14C dates, together with ages on nine interbedded tephras or cryptotephras in three peat cores from each of Kopouatai and Moanatuatua bogs in the Waikato region of North Island to attain a new age for Tūhua tephra, which occurs in all six cores. In applying the Bayesian P_sequence routine of OxCal, the Tūhua tephra was ‘cross- referenced’ (i.e., set as being the same instantaneous event) in each of the cores, and thus the modelling was ‘isochron informed’. Using SHCal13, the isochron-informed modelling yielded a new age for Tūhua tephra of 7637 ± 100 cal. BP (95.4% PR), older and more precise than previous estimates (Fig. 1). A similar age (~7630 cal. yr BP) was obtained using P_sequence modelling whereby independent ages on Tūhua were estimated for each core without cross-referencing and then amalgamated using Combine. Finally, using the independently-modelled age distributions, we defined Tūhua deposition as a ‘Phase’ set between start and end ‘Boundaries’, and then used OxCal’s Difference function to estimate the ‘Phase’ duration across cores (it should be zero years based on tephrochronology): it ranged from 0‒730 years (95.4% confidence interval), mean 277 years but, reassuringly, was markedly skewed towards zero (i.e., instantaneous). This approach using isochron- informed Bayesian age modelling could be readily applied in settings where one or more tephra or cryptotephra deposits occur in common with sequences of dates in peats or lake sediments in the same cores. The new and more robust age for Tuhua tephra obtained here using the isochron-informed method reinforces its importance as a key chronostratigraphic marker in relation to the New Zealand Holocene sea-level high stand and other early-mid Holocene events. 96

Fig. 1. New 'isochron-informed' mean age for Tuhua tephra (7637 ± 100 cal yr BP, 95.4% probability range).

P 2.9 in Poster session 2: 27.06.2018, 14:00-

Tephra data without borders: Building a global and interdisciplinary tephra data system 1 1 2 3 4 STEPHEN KUEHN , JANINE KRIPPNER , CHERYL CAMERON , SIMON GORING , KERSTIN LEHNERT , 5 6 6 DOUGLAS FILS , AMY MYRBO , ANDERS NOREN 1 Physical Science, Concord University 2 Alaska Volcano Observatory 3 Department of Geography, University of Wisconsin - Madison 4 LDEO, Columbia University 5 Consortium for Ocean Leadership 6 LacCore-CSDCO, University of Minnesota Contact: [email protected]

As chronostratigraphic markers and as records of volcanic events, tephra layers are a common link across multiple disciplines, including volcanology, tephrochronology, archaeology, and paleolimnology among many others. Tephra deposits reflect the magmatic, eruptive, dispersal, and depositional processes that contribute to their formation. They are fundamental in understanding eruption histories, hazards, and impact extent in volcanology. They also provide important, widespread time-stratigraphic markers employed in tephrochronology. Through both traditional and cryptotephra studies, these tephra isochrons can be traced across countries, across whole continents, and sometimes even from one continent to another across intervening ocean basins.

Although tephra deposits may not follow national or continental borders, currently much existing tephra data does. Data that have been collected over decades still lie fragmented in unpublished laboratory or personal data sets or in-house databases, in separate publications, in underutilized datasets produced by separate disciplines, and some in openly- accessible data repositories. These data may include physical (e.g. particle size and layer 97 thickness), geographic location, geochemical, mineralogical, time-stratigraphic, and interpretive information from many separate studies with different research goals. To achieve the aim of tephra data without borders for the benefit of the global tephra community, we must remove these barriers between data types and between data storage locations.

THROUGHPUT is a collaborative pilot project working to increase discoverability of and access to tephra data across disciplines, to improve integration between data types and between data facilities, and to enable the use of digital tools and work flows. Data types to be integrated extend beyond tephra to also include sediment cores and paleoecology, for example. This project also builds upon and seeks to implement developing community best practices for tephra data collection, reporting, and storage. Current project partners include multiple data repositories, research groups, and laboratories, and we seek to engage others in formulating and building the future of tephra data.

P 2.10 in Poster session 2: 27.06.2018, 14:00-

Improved EPMA of tephra glasses using TDI, combined EDS+WDS, MAN, a multi-standard blank correction, and a multi-standard normalization to facilitate smaller beams, more elements, greater precision, and better between-session reproducibility 1 STEPHEN KUEHN 1 Physical Science, Concord University Contact: [email protected]

Analysis of natural and synthetic glasses is a common application of electron probe microanalysis (EPMA). Since the late 1960s, EPMA has remained at the forefront of tephra glass analysis because of the technique’s high spatial resolution, analytical sensitivity, rapidity, cost-effectiveness, and potential for high precision. These attributes make it possible to chemically fingerprint and thereby identify and correlate the deposits of individual volcanic eruptions. This, in turn, enables the development of chronological frameworks using widely- dispersed tephra deposits. Additional applications include magmatic processes, eruption processes, volcanic gasses (e.g. via melt inclusions), atmospheric dispersal of tephra, and the environmental and human impacts of volcanic eruptions.

In recent years, there have been an increasing number of tephra studies which target trace deposits of volcanic ash known as cryptotephra. This has greatly expanded the geographic range of tephra correlation to localities more than 5000 km from their volcanic sources. However, cryptotephra deposits often contain sparse, small grains. Additionally, even visible tephra beds may contain grains with very narrow walls of glass between bubbles or an abundance of microcrysts which also limit the size of target areas available for analysis. Thus, to maximize the amount of data that can be collected, it may be necessary to use smaller electron beam diameters.

In addition, some volcanic centers tend to repeatedly erupt tephras with a very strong “family resemblance” in their geochemistry. Although such closely-clustered compositions may be helpful in attributing tephras to a particular source volcano, distinguishing between individual eruptions becomes much more difficult. Trace-element analysis, e.g. by LA-ICP-MS, is one approach for such situations, but increasing the precision and between-session reproducibility of EPMA analysis and adding more elements can also help. The more precise and additional data can also increase confidence in tephra correlations which rely upon such techniques. Utilization of smaller electron beams can, however, worsen the well-known problem of alkali element migration or “sodium loss” which degrades analytical accuracy. Increasing EPMA precision through greater analysis time and beam current poses a similar accuracy problem. 98

To enable routine, precise, and accurate EPMA of silicate glasses at smaller beam diameters using a broad range of EPMA instrumentation, including older instruments, and to acquire data for additional elements, two analytical methods have been developed. Both utilize (1) a time-dependent-intensity (TDI) correction for time-varying X-ray intensities, (2) mean atomic number (MAN) modelled X-ray backgrounds, (3) a combination of several wavelength- dispersive (WDS) spectrometers with a single high count rate silicon drift detector (SDD) energy dispersive (EDS) spectrometer, (4) an offline multi-standard blank correction, and (5) an offline multi-standard whole-session normalization to better matche analyzed concentrations to reference concentrations. This has been implemented on a 6-WDS spectrometer ARL SEMQ electron microprobe - originally built in the 1980s - with a modern EDS and modern analytical and automation software. The TDI correction enables excellent accuracy for Na, and where needed for K. MAN backgrounds simultaneously reduce analytical time and improve analytical precision. The fast SDD EDS enables Si and Al to be analyzed to high precision in only eight seconds, before count rates for these elements change significantly. The blank correction improves trace-level accuracy, and the normalization improves session-to-session reproducibility. Both the blank and normalization use data from multiple reference materials in combination for reduced statistical variation and reduced dependence on the results from any single reference material. For routine work, a 3- minute analysis at 10 nA produces excellent results for 12 elements (SiO2, TiO2, Al2O3, FeO , MnO , MgO , CaO , Na2O, K2O, P2O5, Cl, and BaO) using beams as small as 6 microns on felsic glasses and 3 microns on mafic glasses. Where more precision and/or more elements are needed, a 5-minute analysis at 40 nA produces results for 20 elements (SiO2, TiO2, Al2O3, FeO , MnO , MgO , CaO , Na2O, K2O, P2O5, Cl, BaO, CoO, Cr2O3, NiO, Rb2O, SO3, SrO, VO2, and ZrO2), albeit at larger beam diameters. Both methods also implement spectral interference corrections (e.g. between Ba and Ti, for Mn on Fe, Ca on Mg, and Ca on P) for better accuracy.

P 2.11 in Poster session 2: 27.06.2018, 14:00-

Deposition, re-working and recycling of Holocene rhyolitic tephra in marine sediments at an active plate margin 1 2 2 JENNI L HOPKINS , RICHARD WYSOCZANSKI , ALAN ORPIN 1 Victoria University of Wellington 2 National Institute of Water and Atmospheric Science, New Zealand Contact: [email protected]

Rhyolitic marker horizons provide critical isochronous tie points for marine sediment cores, however, at active plate margins their characterisation and correlation can be complex. On a recent voyage of the RV Tangaroa (TAN1613) along the north-eastern New Zealand coast, 33 tephra horizons were identified within 17 shallow piston cores. Using deposit morphology, clast composition and glass geochemistry, we characterise these deposits as: (1) primary air fall, (2) reworked volcanoclastic rich turbidites, and (3) discontinuous “blebs” of volcanoclastic material. Detailed geochemical analysis of major and trace elements not only facilitates these characterisations, but also allows cross-correlation between cores, and from horizon to source. Identified tephras include Kaharoa (AD 1314) from the Tarawera complex, Taupo (AD 232) from the Taupo caldera, and an as yet unidentified eruption most likely older than these two. Some of the thicker tephra deposits (>10 cm) exhibit bimodal or multi-modal geochemical signatures, which record the geochemical evolution of the eruption. In addition, we present isopach maps for these eruptions drawn from our distribution of core site locations along a large proportion of the East Coast of New Zealand. The dispersal of the tephra, highlights changes in wind direction, and/or explosivity throughout the eruption sequences.

99

P 2.12 in Poster session 2: 27.06.2018, 14:00-

Recent progress and perspective in tephrochronological studies for eruption histories of Quaternary volcanoes in north Izu Islands, off Tokyo Metropolitan Area, Japan 1 2 3 2 TAKEHIKO SUZUKI , MAKOTO KOBAYASHI , FUMIKATSU NISHIZAWA , KAORI AOKI , DAISUKE 1 1 ISHIMURA , DAICHI NAKAYAMA 1 Department of Geography, Tokyo Metropolitan University 2 Research Center for Volcanic Hazards and Their Mitigation, Tokyo Metropolitan University 3 Mount Fuji Research Institute Contact: [email protected]

Many active Quaternary volcanoes distribute in north Izu Islands, the northern part of Izu- Bonin Arc. Comparing to other Quaternary volcanoes in the Japanese Islands, geomorphological and geological data are not sufficient because most of them are submarine volcanoes or volcanic islands with limited land areas. Nine volcanic islands with residents (Izu-Oshima, Toshima, Nijima, Shikinejima, Kozushima, Miyakejima, Mikurajima, Hachijojima and Aogashima) are active volcanoes, requiring volcanic disaster measures for future eruptions using continuous geophysical observations, hazard maps, evacuation plans and reconstruction of past eruption properties (eruption succession, mode of eruption, magnitude, age and so on). Geological mapping and eruption histories constructed by tephrochronology for each volcano are efficient for this purpose. However, those have not uniformly achieved, also showing insufficiencies in volcanological studies. Here, we review previous tephrochronological studies and show perspectives together with new tephra database in this area.

Nijima and Kozushima are originated from rhyolitic magma. On both volcanoes, the last explosive eruption occurred in 9thcentury, followed by dormant period until present. The eruption histories for these volcanoes have been explored through geomorphological and geological methods by previous studies. Sequences of volcanic products during last 30 krys on both islands have been proposed using widespread AT Tephra (30 ka; Smith et al., 2013) (Yoshida, 1992; Suga et al., 2003). However, different histories in the southern part of Kozushima composed of monogenetic volcanoes were proposed by several authors such as Suga et al. (2003) and Yokoyama et al. (2003). Other problems left in the island are scarcity of reliable radiometric ages before 30 ka, unclear relation between many monogenetic volcanoes and tephras, suggesting advantages of geomorphic analysis using the airborne laser survey and detailed description of tephras. We reported recent studies on both islands; that is, landforms of both islands, tephra sequence in middle to north Nijima (Kobayashi et al., 2018) and eruption history of Kozushima (Nishizawa et al., 2018; Ito et al., 2018).

Izu-oshima and Miyakejima originated from basaltic magma have frequently erupted recently, suggesting next eruptions in near future. Due to the large number of eruptions, eruption history studies have been carried out since 1960s (Izu-oshima: Nakamura, 1964; Koyama & Hayakawa, 1996; Miyakejima: Tsukui et al., 2005), still publishing new data (Kawanabe, 2012; Oikawa & Geshi, 2010), remaining problems unsolved. For example, precise age of N1 (9 to 11 century) of the Izu-oshima has not been determined, indicated by different ages among literatures (e.g. Tsukui et al, 2006; Kawanabe, 2012). Additionally, precise ages of products roughly erupted from 20 ka to 1.7 ka has not been determined. Moreover, formations of Fudeshima and Okata Volcanoes preceding present volcanic edifice of Izu- oshima have not been well known. Detailed history of Miyakjima was also established, however its older history is not clear despite of recognition of AT Tephra (Nanri & Suzuki, 2014). The history of Hachijojima during longer period of ca. 50 ka was well established (Sugihara, 1998).

Studies of eruption histories on Toshima, Mikurajima and Aogashima have not well done, reflected by older eruptive events occurred at 4 ka (Toshima) and 6 ka (Toshima). New data are required for volcanic disaster measures. 100

In conclusion, the oldest ages in previously constructed eruption histories for each volcano are variable. For establishing longer eruption history, it will be sufficient to survey underground geology although it is limited. Moreover, identification of tephras covering on distant islands will effective. Especially, rhyolitic tephras derived from Nijima and Kozushima have already identified on not only north Izu Islands (Sugihara et al., 2005; Sato et al., 2006) but also on further main Japanese Islands such as the foot of Mt. Fuji (Kobayashi et al., 2007) and Suigetsu Lake in Fukui (McLean et al., 2018) where Kozushima-Tenjo Tephra (AD838) was found. It is needed to focus on distal tephras from Izu Islands to revise eruption history. For this, fundamental studies on marine tephra in and around Izu Islands, preparation of tephra database (Aoki et al., 2018) and discrimination of similar tephras (e.g. from Nijima and Kozushima) (Suzuki et al., 2017) are needed.

P 2.13 in Poster session 2: 27.06.2018, 14:00-

A ~260-ka eruptive history for Kilimanjaro derived from Lake Challa sediments 1 1 2 3 CATHERINE MARTIN-JONES , CHRISTINE LANE , CHRISTIAN WOLFF , MAARTEN VAN DAELE , 4 5 6 7 8 THIJS VAN DER MEEREN , DARREN MARK , PHIL BARKER , MAARTEN BLAAUW , MELANIE LENG , 6 9 BARBARA MAHER , DIRK VERSCHUREN 1 Department of Geography, University of Cambridge, Downing Place, Cambridge CB2 3EN, UK 2 Max-Planck Institute for Chemistry, Mainz, Germany 3 Renard Centre of Marine Geology, Ghent University, Ghent, Belgium 4 Department of Biology Ghent University Ghent, Belgium 5 Scottish Universities Environmental Research Centre, UK 6 Lancaster Environment Centre, Bailrigg, University of Lancaster, UK 7 School of Natural and Built Environment, Queen's University Belfast, UK 8 NERC Isotope Geosciences Laboratory, British Geological Survey, UK 9 Limnology Unit, Department of Biology, Ghent University, Gent, Belgium Contact: [email protected]

The iconic Mount Kilimanjaro is Africa’s highest peak and most popular geotouristic attraction. Volcanism began here at ~2.5 Ma with activity focussed on three laterally aligned centres, Shira, Kibo and Mawenzi, until ~200 ka (Nonette et al., 2008). Since then Strombolian activity from as many as 250 parasitic cones on the SE flanks of the mountain has dominated the record. Fumarolic activity continues at Kilimanjaro and many of the cones are of suspected Holocene age, yet the volcanic threat that this poses to the 2.6 million people living within a 100-km radius remains unconstrained (Brown et al., 2015). Improved cataloguing of the frequency and relative size of past eruptions is essential if we are to assess the potential for, and possible impacts of, further eruptions from Kilimanjaro.

Deep lakes preserve volcanic ash (tephra) layers in their stratigraphically-resolved sediment sequences, often offering the most complete window into past explosive volcanism. The new DeepCHALLA sediment core from Lake Challa, located on the Kenya-Tanzania border and in the shadow of Kilimanjaro, provides a high-resolution paleoenvironmental record for tropical Africa, as well as a detailed record of explosive volcanism extending to ~260 ka. This finely laminated sediment sequence contains thirty visible tephra horizons, many of which are distinctive in terms of their physical and geochemical properties. Six of these tephra layers contain basaltic glass shards with major and minor element compositions that we confidently match to published data on the lavas from Kilimanjaro’s <200-ka parasitic cones.

Here we use Lake Challa tephrostratigraphy to infer the eruptive history of Kilimanjaro. We confirm that its latest phase of volcanism was confined to Strombolian activity. The earliest tephra layer we have sampled lies at the base of the DeepCHALLA sequence, currently dated to ~260 ka. Five further eruptions are recorded, but activity appears to have ceased around ~70 ka. However, future investigation of microscopic cryptotephra horizons may yield evidence of younger activity. We show the potential for lake sediments to shed light on past 101 volcanic activity and future volcanic hazard throughout the rapidly developing East African Rift.

References Brown, S. K. et al., 2015. Regional and country profiles of volcanic hazard and risk. Report IV of the GVM/IAVCEI contribution to the Global Assessment Report on Disaster Risk Reduction Nonnotte, P., et al., (2008). New K–Ar age determinations of Kilimanjaro volcano in the North Tanzanian diverging rift, East Africa. Journal of Volcanology and Geothermal Research, 173(1), 99- 112.

P 2.14 in Poster session 2: 27.06.2018, 14:00-

Towards improved constraints on the timing of deep-water ventilation changes and the marine reservoir effect in the Southern Ocean between 40-10 kyr BP: A tephrochronological and radiocarbon approach 1 1 2 3 4 PETER ABBOTT , SAMUEL JACCARD , STEVE BARKER , JULIA GOTTSCHALK , LUKE SKINNER , 5 CLAIRE WAELBROECK 1 Institute of Geological Sciences, University of Bern, Switzerland 2 School of Earth and Ocean Sciences, Cardiff University, UK 3 Lamont-Doherty Earth Observatory, Columbia University, USA 4 Earth Sciences Department, University of Cambridge, UK 5 Laboratoire des Sciences du Climat et de l’Environnement, Université de Paris-Saclay, France Contact: [email protected]

Establishing tighter constraints on phase relationships between sedimentary evidence for deep-water ventilation and associated outgassing of carbon dioxide (CO2), and ice-core evidence for past atmospheric CO2 variations can help in testing models of past relationships between climate and CO2. The rate and timing of deep-water ventilation can be determined through paired 14C dating of planktonic and benthic foraminifera in marine sequences, however, uncertainty still exists regarding the temporally variable marine reservoir effect, the age offset between the atmosphere and surface waters. Providing independent age control for marine sequences and/or directly synchronising the marine and ice-core records can provide constraints on the reservoir effect and aid comparisons between these records. This can be achieved using tephrochronology, with common horizons of volcanic ash traced between palaeoclimatic sequences acting as time-synchronous tie-lines due to their rapid deposition. This allows ages unaffected by the reservoir effect (e.g. terrestrial 14C, Ar/Ar, ice- core) to be transferred into the marine chronologies.

We are applying this approach within the Atlantic sector of the Southern Ocean, a key area for the release of CO2 via deep-water ventilation during the deglaciation that has several upwind volcanic systems known to have deposited volcanic ash over the region. Two marine cores with pre-existing ventilation age estimates (MD07-3076Q and TN057-21) are currently under investigation using recently developed methods for the identification of marine cryptotephras, ash horizons not visible upon core inspection. Here we report on the initial results of these investigations and discuss the future potential for the tephrochronological correlation of these records to Antarctic ice-core records and/or proximal sequences and further constraining marine reservoir estimates and ventilation age reconstructions from these sequences.

102

P 2.15 in Poster session 2: 27.06.2018, 14:00-

Five magma bodies fed the ~75 ka Youngest Toba eruption: tephra glass evidence for YTT magma storage and discharge. 1 2 3 4 NICHOLAS PEARCE , GUILHERME GUALDA , JOHN WESTGATE , EMMA GATTI 1 Department of Geography & Earth Sciences, Aberystwyth University, Wales, UK 2 Department of Earth & Environmental Sciences, Vanderbilt University, TN, USA 3 Department of Geology, University of Toronto, ON, Canada 4 Department of Geology and Planetary Sciences, California Institute of Technology, CA, USA Contact: [email protected]

The Toba Caldera Complex is the largest Quaternary caldera on Earth, and has generated three voluminous and compositionally similar rhyolitic tuffs, viz. the Oldest (OTT, 800 ka), Middle (MTT, ~500 ka) and Youngest Toba Tuffs (YTT, 75 ka). These tephra deposits are widespread across Indonesia, Malaysia, South China Sea, Sea of Bengal, India and Indian Ocean and provide useful stratigraphic markers in oceanic, lacustrine and terrestrial environments. Single shard trace element analysis of these deposits reveals the availability of different batches of magma through time, with combinations of compatible and incompatible trace element contents defining 5 discrete magma populations in YTT, 4 populations in MTT but only a single population in OTT. These trace element differences enable the different eruptions to be clearly and easily identified, something that cannot be achieved for the widespread Toba deposits using EPMA major element glass analyses (except for MTT), or through analyses of biotites (where only YTT can be distinguished by Fe/Mg ratios). Within an individual eruption these populations are clearly distinct, but between eruptions (e.g. MTT and YTT) some of these populations broadly overlap, while others do not. This suggests that there has been a long-lived magma source, generating melts of a similar composition (probably from essentially the same source) episodically over ~800 ka, and leading to the assembly of eruptible volumes of melt every few hundred ka.

Of the three major Toba deposits, YTT is by far the most extensive. We have collected an extensive database of glass compositional data for this deposit, with ~500 EPMA and ~2500 trace element analyses. When large numbers of glass shard analyses are plotted, it becomes apparent that YTT can be divided into 5 distinct magma populations (termed I – V) based on their Ba-Y, Ba-Sr and Sr-Y compositions. Population I has the lowest Ba and Sr, population V the highest. These separate populations cannot be distinguished within the major element analyses alone. However, dividing the major element compositions into groups based on their trace element compositions, shows that these too display a systematic compositional change, with subtly higher FeO, CaO, MgO and TiO2 in the lowest SiO2 populations (IV and V). Lower SiO2 in populations IV and V is also associated with generally lower incompatible element concentrations (Y, REE, Th, U) than populations I-III, indicating a systematic variation in the range of magma compositions.

Calculations of the equilibration pressures and temperatures using Rhyolite-MELTS (Gualda and Ghiorso, 2014) from average YTT population compositions (Ni-NiO buffer, water saturated, quartz + 2 feldspars) indicates that magmas were stored at pressure of ~100 MPa (populations I and II), 125 MPa (population III) and ~150-160 MPa (populations IV and V) prior to the eruption of YTT. The pressures of magma storage are equivalent to depths of between ~3.7 - 6 km. Calculations on compilations of published analyses across the YTT fallout give a similar range of equilibration pressures. These calculated pressures of magma storage coincide with the seismically near-isotropic zone below the caldera at depths less than ~7 km, the region assumed to have been affected by the YTT eruption (Jaxybulatov et al. 2014).

With such a large number of analyses, the proportion of different populations of glass in YTT deposits potentially gives an indication of the relative volumes of available magma. Overall, populations I and III glass (lower Ba, Sr, higher SiO2) are the most abundant compositions representing about 70% of the erupted YTT material; the higher Ba, lower SiO2 populations 103

IV and V are the least abundant at ~10% in total. Population II (high SiO2, low Ba, Sr, ~100 MPa) comprises about 17% of the glass shards. However, there are some subtle spatial differences in the proportions of different populations of glass in the tephra fall deposits, and also between pumices and free glass. Population V glass is relatively less abundant in the distal fallout (~4%) than it is in the free glass shards of the caldera walls (~15%). There are also changes in the compositions of pumices with stratigraphic height in the proximal ignimbrite deposits, with ~20% of the glass in early deposited pumices being of population V, this increase in part at the expense of lower Population II glass in the pumice.

It seems likely that the spatial and temporal differences in glass/pumice compositions may reflect a change in magma availability during the eruption. An initial phase (providing less ash available for transport to distal localities) may have tapped the population I (shallow, 100 MPa) and IV and V (deep, ~150-160 MPa) magma bodies, which gradually shifted to a later, more intense phase of the eruption dominated by shallower magma from populations I, II and III (100-125 MPa), with a lesser contribution from IV, and only a little V. This later eruptive phase (poor in population V) appears to have provided the fine ash which was transported more distally, the majority of this material likely being supplied from co-ignimbrite clouds which had buried (isolated) earlier phases of the eruption.

References Gualda and Ghiorso 2014. Phase-equilibrium geobarometers for silicic rocks based on rhyolite- MELTS. Part 1: Principles, procedures, and evaluation of the method. Contrib. Mineral. Petrol., 168, 1033 Jaxybulatov et al. 2014. A large magmatic sill complex beneath the Toba caldera, Science, 346, 617- 619.

P 2.16 in Poster session 2: 27.06.2018, 14:00-

YTT ash from Purna alluvial basin, Central India: its comparison with Toba ashes from continental deposits of India 1 1 ASHOK K. SRIVASTAVA , AJAB SINGH 1 Geology, SGB Amravati University, Amravati Contact: [email protected]

The study provides an insight of YTT ash from Purna alluvial basin (PAB), Central India and its comparison with other Toba ashes preserved in various other river basins of India viz., Ghoghara and Khuntheli sections of Son basin, Pawlaghat and Hirapur locations of Narmada basin, Tejpur site of Madhumati river, Bori locality of Kukadi basin, Morgaon site of Karha valley, Jwalapuram locality of Jurreru valley, Vankamari and Nandipalle sites of Sagileru basin and Simbhora locality of Wardha river.

YTT ashes, presently explored from eight different localities in PAB, are hosted in yellowish brown, thinly laminated, fine sand-silty-clay lithocolumns as pockets, lenticles and discontinuous beds with the thickness of 0.5 to >3 m. It is marked by light gray, yellowish brown to grayish orange pink colours, loose admixture of dominantly clay size fraction alongwith silt to fine sand-size grains of glass shards and minerals. It is both primary and reworked in nature having thickness range of 0.05-0.2 m and ~1-3 m respectively. Major elements of glass shards show higher values of Si, Al, K and Na, whereas, REE trend shows negative gravity anomaly. 40Ar/39Ar dating of glass shards from Gandhigram and Hudki areas suggests 79±0.2 ka and 77±0.5 ka ages respectively.

Comparing YTT ash of PAB with those of other continental Toba ashes reveals a lot similarities, however, dissimilarities too in their various aspects i.e., lithological architecture of the host succession, colour, nature of preservation, geochemical signature, age etc. The host 104 sediments for most of the ashes are fine sand-silt-clay, however, at Pawlaghat, Tejpur and Jwalapuram localities, it occurs in sandy facies. Preservations of ashes at various locality are mostly in the form of pockets, lenticles and thin discontinuous beds having 0.05-0.5 m thickness but, comparatively high up to >3 m thick at Kapileshwar locality of PAB and Jwalapuram. It is mostly reported to be both primary and reworked in nature. The previous is white to light gray, powdery, massive to laminated and >0.04-0.15 m thick whereas, reworked ash is comparatively thicker up to >2.5 m, light yellow, light to medium brown and pinkish orange in colours, comparatively coarse, loose admixture of fine sand, silt and clay size sediments with parallel and cross beddings, ripple laminations and fine sand size laminae.

Geochemical analysis of glass shards from Son valley sites, Pawlaghat, Bori, Jwalapuram and Sagileru, showing high percentage of major oxides, suggests rhyolitic magma and negative gravity anomaly of REE trend. Data from Morgaon and Simbhora are either insufficient or, not available. 40Ar/39Ar dates of 74.7±4.1 ka from biotite of Ghoghara and 73.9±4.4 ka from Jwalapuram suggest YTT age. Similarly, OSL dates for Khuntheli (81±15 ka), Ghoghara (82±13 ka) and Tejpur (71±9 ka) and fission track of glass shards from Gandhigram (84±16 ka) and Pawlaghat (121±22 ka) also suggest the same i.e., YTT. However, 40Ar/39Ar date of 538±47 ka (sanidine), 640±290 ka by fission track and 714±62 ka by 40Ar/39Ar of glass shards for Bori locality are far away from YTT and approaches towards MTT and OTT. 40Ar/39Ar dates on glass shards i.e., 809±51 ka for Morgaon, 797±45 ka for Gandhigram and 827±39 ka for Simbhora favors OTT age. Certain localities viz., Morgaon, Bori, Pawlaghat, Jwalapuram show preservations of Acheulean artifacts close to ash bed which are well investigated for their archeological aspects.

The comparative data shows a restricted approach of study with focus on age determination and geochemistry of tephra. Its use in paleoclimatic reconstructions on local and regional scales is still in primary stage or, missing. Our study clearly shows the existence of various tools i.e., rhizolith balls, rhizospheres, root casts, pedogenic & non-pedogenic calcretes and vertebrate remains in PAB that can be used as proxies to understand the impact of ash cloud on climate, existing fauna and flora. Besides, certain gaps in the study also needs to be filled i.e., i) limited geochemical data from Tejpur locality, ii) confirmation of tephra age of Morgoan and Bori localities, iii) debatable ages from Gandhigram locality etc. The authors also feel the necessity, i) to generate one-time data through same technique/s on age and geochemistry of ashes reported from different areas, and ii) to investigate various biogenic and non- biogenic structures that serve as proxies of climate with an objective to find out the impact of climate on flora, fauna, and human population due to Toba ash.

105

P 2.17 in Poster session 2: 27.06.2018, 14:00-

New insight into frequency of ash fall impacting the Auckland region, New Zealand 1 2 3 2 ALEKSANDRA ZAWALNA-GEER , JAN LINDSAY , SIWAN DAVIES , PAUL AUGUSTINUS , SARAH 4 DAVIES 1 University of Exeter, UK 2 University of Auckland, New Zealand 3 Swansea University, UK 4 Aberystwyth University, UK Contact: [email protected]

Auckland, the largest city in New Zealand, accommodates a third of the country’s population and is built on the basaltic Auckland Volcanic Field (AVF). The AVF has been active since ca. 250 ka and the latest eruption occurred ca. 600 years ago (Lindsay et al., 2011). The hazardous city's location necessitates a better understanding of the frequency of volcanic activity within the AVF. The spatio-temporal context of past AVF activity is poorly understood due to erosion of surface features and poor age control resulting from several dating problems (McDougall et al., 1969; Cassata et al., 2008). In addition to the risk from the AVF, the Auckland region is also exposed to rhyolitic and andesitic ash falls produced by distant volcanoes in the central North Island (Taupo Volcanic Zone, Egmont and Mayor Island volcanic centres).

Assessment of the ash fall hazards posed by future volcanism in the AVF and distal volcanic centres can be achieved by determining the frequency of ash layers interbedded within lacustrine sediments deposited in the Auckland maars. Tephrochronology of the maar lakes contributes to the recognition of AVF eruptive patterns not evident in the distribution of volcanic landforms alone. Previous studies on tephrochronology of the maar lakes allowed the recognition of 24 rhyolitic, 58 andesitic and 24 basaltic tephra layers and contributed to establishing a frequency of ash falls over 80 ka averaging one event per 700 years (e.g., Molloy et al., 2009). Based on those macrotephra results Auckland has been affected by one ash fall event every 1780 years during the Holocene.

Some past known eruptions are not evident as visible tephra layers in the cores and their absence has been explained by unfavourable wind conditions (Shane, 2005). For instance, Egmont volcano produced over 100 eruptions in the Holocene but only one Egmont-sourced tephra layer was recognised in the Holocene record in Auckland. In the revised study investigation of cryptotephra (tephra horizons with glass shard concentrations too low to form a visible tephra layer) in the core sediments from the Pupuke maar revealed tephra fall events previously unknown in the Auckland area spanning a period of the last 9,400 years (Zawalna-Geer et al., 2016). Eight rhyolitic, seven andesitic and one basaltic cryptotephra horizons were identified together with five macrotephra layers. These results indicate that the Auckland region has been affected by ash fall on average every 400 years in the Holocene, with the Taupo Volcanic Centre being the main contributor during this time period.

In addition to the new insight gained into tephra-fall events in the Auckland region, examination of cryptotephra records highlights also extensive upward reworking of the glass shards in a lake with a closed and limited catchment. For some sediment records, elevated glass shard concentrations in sediments could be mostly artifacts of reworking rather than the signal of new ash fall events. Geochemical fingerprinting of glass shards, stratigraphic correlation, radiocarbon dating, X-ray fluorescence and magnetic susceptibility core scanning results were employed to distinguish between primary and reworked tephra units and confidence level were attached to newly identified cryptotephra. A consideration of post- depositional processes is critical not only for the interpretation of the cryptotephra record but also in the other paleo-environmental studies.

References 106

Lindsay, J. M.; Leonard, G. S.; Smid, E. R. and Hayward, B. W., 2011. Age of the Auckland volcanic field: A review of existing data. New Zealand Journal of Geology and Geophysics, 54, 379-401. McDougall, I.; Polach, H. A. and Stipp, J. J., 1969. Excess radiogenic argon in young subaerial basalts from the Auckland volcanic field, New Zealand. Geochimica et Cosmochimica Acta, 33, 1485-1520. Molloy, C.; Shane, P. and Augustinus, P., 2009. Eruption recurrence rates in a basaltic volcanic field based on tephra layers in maar sediments: Implications for hazards in the Auckland volcanic field. Geological Society of America Bulletin, 121, 1666-1677. Shane, P., 2000. Tephrochronology: A New Zealand case study. Earth - Science Reviews, 49, 223. Shane, P., 2005. Towards a comprehensive distal andesitic tephrostratigraphic framework for New Zealand based on eruptions from Egmont volcano. Journal of Quaternary Science, 20, 45-57. Zawalna-Geer, A., Lindsay, J. M., Davies, S., Augustinus, P., & Davies, S., 2016. Extracting a primary Holocene crytoptephra record from Pupuke maar sediments, Auckland, New Zealand. Journal of Quaternary Science, 31(5), 442-457.

Poster session 3

P 3.1 in Poster session 3: 28.06.2018, 14:00-

Preliminary results from the PAGES* project (*Pleistocene Archaeology, Geochronology and Environment of the Southern Caucasus) 1 2 3 1 2 RHYS TIMMS , JENNI SHERRIFF , KATIE PREECE , SIMON BLOCKLEY , KEITH WILKINSON , 3 4 DARREN MARK , DANIEL ADLER 1 Geography, Royal Holloway, Royal Holloway University of London, UK 2 Department of Archaeology and Anthropology, University of Winchester, UK 3 Scottish Universities Environmental Research Centre, UK 4 Department of Anthropology, University of Connecticut, USA Contact: [email protected]

The Southern Caucasus, consisting of modern day Armenia, Azerbaijan and Georgia, are critically placed for understanding the timing and nature of human dispersal during the Pleistocene. Recent archaeological investigations have revealed the oldest known evidence of human fossils outside Africa (Dmanisi; Dennell et al., 2003), and the earliest evidence of advanced technological behaviour (Nor Geghi 1; Adler et al., 2014). Despite these globally significant discoveries, it is presently unclear: i) how long humans may have persisted in the region; ii) how their presence may have fluctuated with the rhythms of climate, and; iii) how these early pioneers may have be affected by regional volcanic processes.

The multi-disciplinary PAGES project aims to develop a robust and independent geochronological framework for the Southern Caucasus, focussing specifically on the use of geological mapping, (crypto)tephrochronology and 40Ar/39Ar dating to link palaeoenvironmental and archaeological sequences in the region. Here we present the preliminary results from a number of ongoing archaeological excavations and sampling of palaeoenvironmental sequences situated in the Hrazdan and Debed river valleys, Armenia. This data will be used to develop a regional model of human habitation and dispersal, and the role of environmental change in these processes. This research will contribute to a greater understanding of the dynamics of human mobility, technological change and hominin evolution during the Pleistocene.

References Adler, D.S. et al. 2014: Science 345, 1609-1613. Dennell, R., 2003: Journal of Human Evolution 45, 421-440.

107

P 3.2 in Poster session 3: 28.06.2018, 14:00-

DBTG-Danube Basin Tephra Geodatabase 1 1 2 3 MILICA RADAKOVIC , RASTKO MARKOVIC , DANIEL VERES , ULRICH HAMBACH , MILIVOJ 1 4 5 6 7 GAVRILOV , IGOR OBREHT , CHRISTIAN ZEEDEN , FRANK LEHMKUHL , HAO QINGZHEN , 1 SLOBODAN MARKOVIC 1 Department of Physical Geography, University of Novi Sad 2 Romanian Academy, Institute of Speleology, Clinicilor 5, Cluj-Napoca 400006, Romania 3 BayCEER& Lehrstuhl für Geomorphologie, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany 4 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, 28359 Bremen,Germany 5 IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ Paris 06, Univ Lille, 75014 Paris, France 6 Department of Geography, RWTH Aachen University, Templergraben 55, 52056, Aachen, Germany 7 Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, CAS, Beijing, China Contact: [email protected]

Tephrochronology provides an essential tool for linking, dating, and synchronizing geological, palaeoenvironmental, and archaeological records. Over past few decades, tephra was found in many Loess Paleosol Sequences (LPS) in the Danube Basin. The lowland area of the Danube Basin I surrounded by several major volcanic fields, including the nearby Carpathian, western and central European eruptive zones, as well as the more distal, but exceptionally eruptive central and eastern Mediterranean volcanic provinces. Several tephra layers deposited during the Middle and Late Pleistocene were found in the Danube Basin loess. The most prominent tephras are the Bag tephra in loess unit L4 (MIS 10), undefined tephra(s) in the penultimate glacial loess L2 (MIS 6), the Paks tephra in the lower part of loess unit L1 (MIS 4) and Campanian Ignimbrite (CI/Y5) tephra in the last glacial loess L1 (MIS 3), which originated in the Campi Flegrei region of central Italy around 39-40 ka. Moreover, initial rock magnetic investigations and visual inspections indicate the potential occurrence of several additional crypto-tephras, such as in the upper part of the distinct pedocomplex S5 and at the very base of loess L3 unit. These results highlight the important role of tephra layers as reliable correlative marker horizons at sub-continental scale and as robust chronostratigraphic markers, especially when these are traced back to their sources and independently dated.

The idea of DBTG (Danube Basin Tephra Geodatabase) is inspired by increasing number of discovered tephras in numerous LPS investigated in Serbia, Romania and Hungary. Nevertheless, a systematic database allowing for clear and detailed tephra distribution is yet missing. The DBTGwill be presented as a map with the spatial distribution of reported tephras in Danube loess, allowing for a better understanding of its extent of deposition. It will be created via the ArcMap software, and then published and presented as an online map, on ArcMap Online website. Тhe information about tephra (stratigraphic position, mineralogy, origin, relevant literature, etc.) will be stored in the form of attributes of spatial (and nonspatial) tables, which will open by clicking on their location on the map.

The DBTG will be an easy way to present the new discoveries in tephrochronology, by simply adding more information to the specific location on the map. This geodatabase will be a useful tool for different study disciplines as it could be used not only for mapping tephra found in LPS, but in every other geologic or geomorphologic setting.

108

P 3.3 in Poster session 3: 28.06.2018, 14:00-

Tephra marker horizons in loess records from southeastern Europe 1 2 3 4 5 DANIEL VERES , ULRICH HAMBACH , ALIDA TIMAR-GABOR , SABINE WULF , CHRISTIAN ZEEDEN , 6 7 8 8 IGOR OBREHT , JANINA BÖSKEN , MILICA G. RADAKOVIĆ , SLOBODAN B. MARKOVIĆ , FRANK 7 LEHMKUHL 1 Institute of Speleology, Romanian Academy, 400006 Cluj-Napoca, Romania and Interdisciplinary Research Institute on Bio-Nano-Science of Babes-Bolyai University, Treboniu Laurean 42, 400271 Cluj-Napoca, Romania 2 BayCEER&Chair of Geomorphology, University of Bayreuth, D-95440 Bayreuth, Germany 3 Interdisciplinary Research Institute on Bio-Nano-Science of Babes-Bolyai University, Treboniu Laurean 42, 400271 Cluj-Napoca, Romania and Faculty of Environmental Science and Engineering, Babes-Bolyai University, 400294 Cluj-Napoca, Romania 4 Department of Geography, University of Portsmouth, Buckingham Building, Lion Terrace, Portsmouth PO1 3HE, UK 5 IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ Paris 06, Univ Lille, 75014 Paris, France 6 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Leobener Str. 8, 28359 Bremen, Germany 7 Department of Geography, RWTH Aachen University, Templergraben 55, D-52056 Aachen, Germany 8 Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia Contact: [email protected]

The use of volcanic ashes in addressing chronostratigraphic issues for terrestrial records such as loess has gained considerable advance. For example, the Campanian Ignimbrite/Y-5 tephra, the product of one of the largest late Quaternary explosive events in the Mediterranean is now the most important chronologic and stratigraphic marker for loess and other records from western Eurasia. Dated to 39-40 ka BP, it provides an independent basis for establishing age-depth relationships for the embedding deposits and for comparing records on a wider scale. Motivated by its widespread occurrence in the Danube loess, we conducted detailed paleoclimate investigations of selected loess sites corroborated by the dating through (mainly) luminescence dating methods. One aim was to test for the reliability of different luminescence dating methods in that narrow age-range around 40 ka BP. In general the luminescence age estimates confirm that the volcanic ash occurrences represent a regionally synchronous depositional event, around 40 ka in age, albeit considerable chronological variability has been observed. These results provide, however, the needed sedimentological framework for testing models of tephra accumulation, preservation and impact on the paleoenvironment. Further, comparison of magnetic susceptibility and grain size records from the longest measured loess profiles in the Danube loess, extending to Early Pleistocene, show that a number of macroscopically visible ash layers could be identified alongside a range of cryptotephra horizons. Albeit most of these tephra layers have been altered and preserve no glass shards, we show that they offer potential in providing correlation tie-points. Based on this, we explore the potential of tephrostratigraphic and tephrochronological investigations in linking loess profiles in southeastern Europe, as well as loess with other records such as marine and lake sediments.

109

P 3.4 in Poster session 3: 28.06.2018, 14:00-

Geochemical, sedimentological, and chronological considerations of several Late Quaternary key marker tephra of Carpathian origin 1 2 3 4 DANIEL VERES , VALENTINA ANECHITEI-DEACU , DÁVID KARÁTSON , SABINE WULF , ALIDA 2 5 6 6 6 TIMAR-GABOR , ULRICH HAMBACH , FRANK LEHMKUHL , STEPHAN PÖTTER , JANINA BÖSKEN , 7 8 9 ENIKŐ MAGYARI , IGOR OBREHT , SLOBODAN B. MARKOVIĆ 1 Institute of Speleology, Romanian Academy, 400006 Cluj-Napoca, Romania and Interdisciplinary Research Institute on Bio-Nano-Science of Babes-Bolyai University, Treboniu Laurean 42, 400271 Cluj-Napoca, Romania 2 Faculty of Environmental Science and Engineering, Babes-Bolyai University, 400294 Cluj- Napoca, Romania and Interdisciplinary Research Institute on Bio-Nano-Science of Babes- Bolyai University, Treboniu Laurean 42, 400271 Cluj-Napoca, Romania 3 Department of Physical Geography, Eötvös University, H-1117 Budapest, Hungary 4 Department of Geography, University of Portsmouth, Buckingham Building, Lion Terrace, Portsmouth PO1 3HE, UK 5 BayCEER & Chair of Geomorphology, University of Bayreuth, 95440 Bayreuth, Germany 6 Department of Geography, RWTH Aachen University, Templergraben 55, D-52056 Aachen, Germany 7 MTA-MTM-ELTE Research Group for Paleontology, Eötvös University, H-1117 Budapest, Hungary 8 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Leobener Str. 8, 28359 Bremen, Germany 9 Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia Contact: [email protected]

The usefulness of tephra in addressing chronostratigraphic issues has gained considerable advance. Motivated by the premise that the Carpathian volcanism may have played an important role in providing Late Quaternary tephra marker horizons for central-eastern Europe, we initially surveyed several loess and loess-derivate profiles harboring pyroclastic fall and flow deposits in both proximal and more distal locations nearby Ciomadul, the youngest volcanic center in Romania. Here we discuss results of the geochemical, chronological, and sedimentological investigations of Targu Secuiesc loess profile, circa 25 km east of Ciomadul volcano. Through multi-method luminescence dating we show that the circa 15 m thick sequence preserves an environmental record covering the Last Glacial Cycle. Geochemical and mineralogical data allow the identification of three key tephra units of rhyolitic composition, clearly pointing to resurgent eruptions of geochemically rather similar magmas of the Ciomadul volcano. Detailed investigations helped to establish petrological affinities for defining provenances and precise correlations of these tephra layers with published data (Karátson et al., 2016; Wulf et al., 2016). Tephra ages have been constrained indirectly by luminescence and radiocarbon dating of embedding deposits (Karatson et al., 2016; this work), or through direct zircon dating of the pyroclastic products (Harangi et al., 2015). These proximal tephra are geochemically similar to some distal volcanic ashes from loess deposits in central Romania and up the loess fields north of the Black Sea. Therewith, our results confirm long-held views (Szakács and Seghedi, 1998) that the Carpathian volcanic activity could provide chronological constraints in providing marker horizons of regional significance.

References Harangi, S., Lukács, R., Schmitt, A.K., Dunkl, I., Molnár, K., Kiss, B., Seghedi, I., Novothny, Á., Molnár, M., 2015. Constraints on the timing of Quaternary volcanism and duration of magma residence at Ciomadul volcano, east–central Europe, from combined U–Th/He and U–Th zircon geochronology. Journal of Volcanology and Geothermal Research 301, 66-80. Karátson, D., Wulf, S., Veres, D., Magyari, E. K., Gertisser, R., Timar-Gabor, A., Novothny, Á., Telbisz, T., Szalai, Z., Anechitei-Deacu, V., Appelt, O., Bormann, M., Jánosi, Cs., Hubay, K., Schäbitz, F., 2016. The latest explosive eruptions of Ciomadul (Csomád) volcano, East Carpathians — A tephrostratigraphic approach for the 51–29 ka BP time interval. Journal of Volcanology and Geothermal Research 319, 29-51. 110

Szakács, A., Seghedi, I., 1998. Premises of tephrological investigation of the Quaternary in Romania. Romanian Journal of Stratigraphy 77, 85-90. Wulf, S., Fedorowicz, S., Veres, D., Łanczont, M., Karátson, D., Gertisser, R., Bormann, M., Magyari, E., Appelt, O., Hambach, U., Gozhyk, P.F., 2016. The ‘Roxolany Tephra’ (Ukraine) − new evidence for an origin from Ciomadul volcano, East Carpathians. Journal of Quaternary Science 31, 565-576.

P 3.5 in Poster session 3: 28.06.2018, 14:00-

Integrating tephrochronology with archaeology, the humanities, and palaeoenvironmental and palaeoclimatic records (dataARC) 1 2 3 4 ANTHONY NEWTON , RICHARD STREETER , COLLEEN STRAWHACKER , ADAM BRIN , RACHEL 5 1 6 OPITZ , ANDREW DUGMORE , TOM MCGOVERN 1 Institute of Geography, University of Edinburgh 2 School of Geography and Sustainable Development, University of St Andrews 3 National Snow and Ice Data Center Cooperative Institute for Research in Environmental Science (CIRES) University of Colorado, Boulder 449 UCB Boulder, CO 80309 4 Digital Antiquity School of Human Evolution and Social Change Arizona State University PO Box 872402 Tempe, AZ, 85287-2402 5 Archaeology, School of Humanities, University of Glasgow University Avenue, Glasgow G12 8QQ 6 Zooarchaeology Laboratory Anthropology Dept. Hunter College CUNY 695 Park Ave NYC 10065 Contact: [email protected]

For over 20 years volcanological and tephrochronological databases (such as Tephrabase) have existed, and they are invaluable tools for researchers around the world. Recent years have seen the development of new systems which add greatly to making tephra data available, comparable and globally accessible. dataARC is a National Science Foundation- funded project which is creating data infrastructure and digital tools to allow scientists and the public to easily access, link and understand the information that is essential to interdisciplinary research. This ongoing project has brought together a wide range of academic researchers together with informatics experts. The research focus is the North Atlantic region from Scandinavia, across northern British Isles, the Faroes, Iceland and Greenland and builds on the work of the North Atlantic Biocultural Organisation (NABO). Tephrochronology plays a key role, especially in Iceland, in building chronological frameworks to date and connect archaeological sites, landscapes and environmental records. In addition classic tephrochronology also aids the reconstruction of past environmental conditions, rates of change and human-environmental interactions. Data from Tephrabase is being integrated into this system and will provide high resolution chronological data for the system.

111

P 3.6 in Poster session 3: 28.06.2018, 14:00-

The geographical extent of the “L2-Tephra”: a widespread marker horizon for the penultimate glacial (MIS 6) on the Balkan Peninsula 1 2 1 1 3 CHRISTIAN LAAG , ULRICH HAMBACH , AKOS BOTEZATU , YUNUS BAYKAL , DANIEL VERES , 1 1 4 5 THOMAS SCHÖNWETTER , JANNIS VIOLA , CHRISTIAN ZEEDEN , MILICA G. RADAKOVIĆ , IGOR 6 7 8 9 OBREHT , MLADJEN JOVANOVIĆ , JANINA BÖSKEN , FRANK LEHMKUHL , SLOBODAN B. 10 MARKOVIĆ 1 Chair of Geomorphology, University of Bayreuth, Germany 2 BayCEER and Chair of Geomorphology, University of Bayreuth, Germany 3 Institue of Speleology, Romanian Academy, Romania 4 IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universites, France 5 Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Serbia 6 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Germany 7 Department of Geography, Tourism and Hotel Management, University of Novi Sad, Serbia 8 Chair of Physical Geography and Geoecology, RWTH Aachen University, Germany 9 Department of Geography, RWTH Aachen University, Germany 10 Chair of Physical Geography, Faculty of Science and Mathematics, University of Novi Sad, Serbia Contact: [email protected]

The magnitude of volcanic eruptions and the volume of ejected magma control amongst other factors the thickness and geographical extent of tephra layers. Here we present and discuss new data on the extent of the “L2-Tephra” preserved in loess-palaeosol sequences (LPSs) on the Balkan Peninsula. Magnetic susceptibility and colorimetric data from the LPSs of Zemun (in the vicinity of Belgrade, Serbia) and Mircea Voda (Dobrogea, Romania) provide new evidence for the western- and easternmost extent of the “L2-Tephra” and shedding new light on the potential magnitude of the environmental impact of the related volcanic event during marine isotope stage (MIS) 6.

Tephra chronology provides independent age control in various sedimentary archives by direct radiometric dating of tephras itself or linking tephras back to their dated volcanic source. With a tephra-based time-frame, sedimentary archives of quite diverse facies can be correlated unambiguously. Such an approach is already realized for several sedimentary archives worldwide and it is intended to be applied also for loess profiles on the Balkan Peninsula (compare Radaković et al., INTAV conference abstract). The “L2-Tephra” could serve as an unambiguous tie point between loess records and other (lacustrine, marine) archives.

We show that the “L2-Tephra”, named after its position in loess unit L2, approximately equivalent to MIS 6 (Marković et al. 2015), could be traced in LPSs of the northern Balkan Peninsula from Croatia (Vukovar) in the West to the Black Sea coast in the East (e.g. Mircea Voda LPS). The “L2-Tephra” is a potential equivalent of one of the tephra layers found in Lake Ohrid (Macedonia) and in the Fucino lacustrine basin (Italy): OH-DP-0617-Vico Ignimbrite B (162± 6 ka), OH-DP-0624-CF-V5-Pitigliano Tuff (163 ± 22 ka) (Leicher et al. 2016) and TF-15, TF-16, TF-17 (dated to 150 - 160 ka) (Giaccio et al. 2017) in Lake Ohrid and Fucino basin, respectively. These widespread tephra layers originated in the Neapolitan area (Italy) and the combined field evidence of increasing “L2-Tephra” thickness from northern Serbia towards the South, gives rise to the assumption that the “L2-Tephra eruption” had a much more severe impact on climate and ecosystems of the Balkan Peninsula (and beyond) than previously thought.

References Giaccio, B., Niespolo, E., Pereira, A., Nomade, S., Renne, P., Albert, P., Arienzo, I., Regattieri, E., Wagner, B., Zanchetta, G., Gaeta, M., Galli, P., Mannella, G., Peronace, E.,Sottili, G., Florindo, F., Leicher, N., Marra, F.& Tomlinson, E. (2017). First integrated tephrochronological record for the last ~ 112

190 kyr from the Fucino Quaternary lacustrine succession, central Italy. Quaternary Science Reviews, 158, 211-234. Leicher, N., Zanchetta, G., Sulpizio, R., Giaccio, B., Wagner, B., Nomade, S., Francke, A. & Del Carlo, P. (2016). First tephrostratigraphic results of the DEEP site record from Lake Ohrid (Macedonia and Albania). Biogeosciences, 13, 2151-2178. Marković, S.B., Stevens, T., Kukla, G. J., Hambach, U., Fitzsimmons, K. E., Gibbard, P., Buggle, B., Zech, M., Guo, Z., Hao, Q., Wu, H., O’Hara Dhand, K., Smalley, I. J., Újvári, G., Sümegi, P., Timar- Gabor, A., Veres, D., Sirocko, F., Vasiljević, D. A., Jary, Z., Svensson, A., Jović, V., Lehmkuhl, F., Kovács, J. & Svirčev, Z. (2015). Danube loess stratigraphy – Towards a pan-European loess stratigraphic model. Earth-Science Reviews, 148, 228-258.

P 3.7 in Poster session 3: 28.06.2018, 14:00-

Multi-proxy-approach in palaeoenvironmental reconstructions using terrestrial sequences from southeastern Transylvania, Romania 1 1 2 3 4 STEPHAN PÖTTER , JANINA BÖSKEN , ULRICH HAMBACH , DANIEL VERES , DÁVID KARÁTSON , 5 6 7 1 SABINE WULF , IGOR OBREHT , SLOBODAN MARKOVIĆ , FRANK LEHMKUHL 1 Department of Geography, RWTH Aachen University, Templergraben 55, D-52056 Aachen, Germany 2 BayCEER & Chair of Geomorphology, University of Bayreuth, 95440 Bayreuth, Germany 3 Institute of Speleology, Romanian Academy, 400006 Cluj-Napoca, Romania and Interdisciplinary Research Institute on Bio-Nano-Science of Babes-Bolyai University, Treboniu Laurean 42, 400271 Cluj-Napoca, Romania 4 Department of Physical Geography, Eötvös University, H-1117 Budapest, Hungary 5 Department of Geography, University of Portsmouth, Buckingham Building, Lion Terrace, Portsmouth PO1 3HE, UK 6 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Leobener Str. 8, 28359 Bremen, Germany 7 Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia Contact: [email protected]

Tephrochronology in terrestrial sediments gained increased attention throughout the last years. Volcanic layers in loess-palaeosol-sequences can be used to enhance the chronostratigraphy and to correlate miscellaneous archives. In southeastern Europe this correlative dating is frequently used, since the region lies in the dispersal area of several regional and supra-regional marker tephra layers. They can be used to put e.g. palaeo- environmental data in a temporal framework. The polygenetic sediment sequence of Bodoc north of Sfântu Gheorghe (Transylvania) and at the bank of the Olt River contains several of such tephra layers. These layers were deposited either subaerial or subaqueous, since this 15 m sequence is of aeolian and fluvial origin. Based on tephra geochemical data and correlations with proximal deposits, we assume the sequence to cover the last glacial cycle. Peculiarly, the sequence shows periglacial features such as ice-wedge casts and cryoturbation, albeit the permafrost boundary during the Last Glacial Maximum is thought to be further north (Vandenberghe et al., 2014). Geochemical, magnetic, granulometric and photometric analyses are conducted to reconstruct the local palaeoenvironmental conditions and their implications for southern Transylvanian palaeoclimate. Moreover, the tephra layers are investigated as well as radiocarbon and luminescence dating are applied to obtain a high-resolution chronostratigraphy.

References Vandenberghe, J., French, H.M., Gorbunov, A., Marchenko, S., Velichko, A.A., Jin, H., Cui, Z., Zhang, T., Wan, X., 2014. The Last Permafrost Maximum (LPM) map of the Northern Hemisphere: permafrost extent and mean annual air temperatures, 25-17 ka BP: The Last Permafrost Maximum (LPM) map of the Northern Hemisphere. Boreas 43, 652–666. https://doi.org/10.1111/bor.12070 113

P 3.8 in Poster session 3: 28.06.2018, 14:00-

Using cryptotephra to link Neanderthal and AMH Middle Paleolithic sites in NW Italy 1 2 2 2 3 JAYDE HIRNIAK , EUGENE SMITH , RACHEAL JOHNSEN , SHELBY FITCH , CALEY ORR , DAVID 4 2 5 6 7 STRAIT , MINGHUA REN , CHRISTOPHER E. MILLER , FABIO NEGRINO , JULIEN RIEL-SALVATORE , 8 9 1 1 MARCO PERESANI , STEFANO BENAZZI , CLAUDINE GRAVEL-MIGUEL , CURTIS MAREAN , JAMIE 10 HODGKINS 1 Institute of Human Origins, School of Human Evolution and Social Change, ASU, Tempe, AZ 85287 2 Department of Geoscience, UNLV, Las Vegas, NV 89154 3 Department of Cell and Developmental Biology, Modern Human Anatomy Program, UC- Denver, Denver, Colorado 4 Department of Anthropology, Washington University in St. Louis, St. Louis, MO 63130 5 Institute for Archaeological Sciences and Senckenberg Centre for Human Evolution and Paleoenvironment, University of Tübingen, 72070 Tübingen, Germany 6 Dipartimento di Antichità, Filosofia, Storia, Università di Genova, Genova, Italy 7 Département d’anthropologie, Université de Montréal, Montréal, Canada 8 Sezione di Scienze Preistoriche e Antropologiche, Dipartimento di Studi Umanistici, Università di Ferrara, Ferrara, Italy 9 Department of Cultural Heritage, University of Bologna, 48121 Ravenna, Italy 10 Department of Anthropology, UC-Denver, Denver, CO 80217 Contact: [email protected]

Establishing robust and reliable chronologies at archaeological sites is essential for understanding the sequence and timing of past events. At Middle and Upper Paleolithic sites like Arma Veirana and Riparo Bombrini, robust chronologies are especially important for answering questions regarding the Middle-to-Upper Paleolithic transition in Europe. Arma Veirana is located in the Ligurian pre-Alps of northwest Italy and Riparo Bombrini is located along the Mediterranean coast, about 80 km away. Both sites have deposits that overlap in age and contain cultural industries attributed to Neanderthals and anatomically modern humans (AMH). Stratigraphic evidence suggests that Neanderthals may have been present at Arma Veirana while AMHs were present at Riparo Bombrini, making it an ideal area to understand the interactions and dynamics of these two species during a key transitional phase. Cryptotephra, also known as microscopic volcanic ash, were recently identified at Arma Veirana in a stratigraphic unit known as the Black Mousterian (BM). AMS radiocarbon dates of charcoal samples collected in the BM, range from 43,781 to 43,121 (68.2%) cal. Yr. BP. Because these dates are close to the measurement limit of radiocarbon, the presence of cryptotephra provides a way to test these existing dates as well as establish a precise isochron to correlate with other sites. Major element chemistry obtained by electron microprobe indicate that the shards found in the BM layers are high silica rhyolite (>75 wt. %) with FeO < 1 wt.%. Trace elements by LA-ICP-MS show depletions in Ba, Sr, and Eu and an enrichment in Th, U and Pb. Both major and trace chemistries show unique geochemical signatures and are rare for volcanoes in the central Mediterranean region. The source volcano is currently unknown; however, this unique chemistry eliminates volcanoes from Iceland, North America, Canaries or Azores, and Aeolian Islands. Potential source volcanoes are located in Turkey (Acigol Dagi Volcano), the Carpathian Mountains (Ciomadul Volcano) and Greece (Nisryos volcano and Santorini Caldera). To test the hypothesis that Neanderthals were displaced from the coast when modern humans arrived in the region, I will take cryptotephra samples at Riparo Bombrini in the summer of 2018 with the goal of directly linking both sites. Identifying the same cryptotephra horizon at Riparo Bombrini will provide an unprecedented temporal correlation between the two sites. This will lead to a better understanding of Neanderthal and AMH interactions during the Middle to Upper Paleolithic transition in Europe. 114

Preliminary shard concentration profile. Sample number is listed along the y-axis and shards per gram of sample are listed on the x-axis. The right side of the figure shows total station located sample profile for AV-651 to AV-664.

P 3.9 in Poster session 3: 28.06.2018, 14:00-

The 4 ka-2 ka cryptotephra record in the Central Mediterranean: new potential isochrones for high-resolution stratigraphy 1 2 3 1 DONATELLA INSINGA , PAOLA PETROSINO , GERT J. DE LANGE , FABRIZIO LIRER , ROBERTO 4 5 SULPIZIO , JIAWANG WU 1 IAMC, CNR-Italy 2 DiSTAR - Dipartimento di Scienze della Terra, dell'Ambiente e delle Risorse – Università degli Studi di Napoli “Federico II” 3 Department of Earth Sciences–Geochemistry, Geosciences, Utrecht University, Utrecht, CD, Netherlands 4 Dipartimento di Scienze della Terra e Geoambientali, Università di Bari, Italy 5 State Key Laboratory of Marine Geology, Tongji University, Shanghai, China Contact: [email protected]

Cryptotephra analysis is a main endeavor for Quaternary studies because it has the potential to address a wide range of scientific questions dealing with e.g. volcanology, paleoclimate and geoarcheology. In this context, the central Mediterranean basin is a favorable study area due to the occurrence of active and productive Italian volcanic vents and its downwind position. In addition, some of its sediments are characterized by high accumulation rates, which makes them suitable for high- and ultrahigh-resolution stratigraphic studies. Here, we report preliminary results on cryptotephra deposits found in a number of marine cores raised 115 in the southern Tyrrhenian, southern Adriatic and Ionian seas, including the Taranto Bay, from the shelf to the deep basin. The cryptotephras were recognized through magnetic susceptibility, elemental composition on bulk sediments, and optical observation of samples prepared for micropaleontological purposes. The characterization in terms of major element composition, obtained through SEM-EDS technique, along with robust age constraints for each core, allowed to relate the analysed deposits to activity of the Somma-Vesuvius, Ischia, Campi Flegrei, Lipari (Aeolian arc) and Mt. Etna during the 4 ka-2 ka time window. According to the tephrostratigraphic framework built for this research, the 79 AD tephra occurs in all the investigated sites with unprecedented findings in southern Adriatic and southwestern Ionian, and at the margin of the Libyan shelf. Hence, this event is a powerful tool to link and synchronise sedimentary archives at ~2 ka BP. In the southern Tyrrhenian, the 79 AD phonolitic population is often found mixed with the trachyphonolitic glasses of Cretaio eruption (Ischia, 60 AD), in the Taranto Bay with Lipari HKCA rhyolites and finally in the southwestern Ionian with Lipari HKCA rhyolitic and Mt. Etna mugearitic glasses. Cryptotephras sourced by Mt. Etna, in detail, characterize the investigated stratigraphic interval in the whole Ionian Sea and this study documents them for the first time in marine settings. They occur in cores at ~ 4 cal ka associated to a Campi Flegrei related population (offshore Santa Maria di Leuca-eastern Taranto Bay), at ~2.2 cal ka (southern Ionian), at ~2 ka (margin of the Libyan shelf) and might be correlated to the terrestrial FS (~4 cal ka), FG (122 BC) and FF (44BC) tephras respectively, which represent regional markers on land. We can include also the FL (~3.4 cal ka) deposits found in the Taranto Bay and already documented up to the Balkans. In order to establish a distinctive proximal-distal correlation, however, a database of single glass chemistry compiled for these Mt. Etna deposits is required since data rely largely on bulk composition. The results presented here are part of a work in progress which aims to contribute to high-resolution stratigraphic studies and to provide new insights on ash dispersal from active Italian volcanoes.

P 3.10 in Poster session 3: 28.06.2018, 14:00-

A tephrostratigraphy for Lake Ioannina, North West Greece 1 1 2 2 3 AMY MCGUIRE , CHRISTINE LANE , KATY ROUCOUX , IAN LAWSON , PAUL ALBERT 1 Department of Geography, University of Cambridge 2 School of Geography and Sustainable Development, University of St Andrews 3 Research Laboratory for Archaeology and the History of Art, University of Oxford Contact: [email protected]

The palaeoenvironmental record of Lake Ioannina (Greece) is an important archive of Quaternary climate and ecological change in the Mediterranean region. The pollen record from Ioannina is argued to contain a clearer representation of vegetation response to millennial-scale climate variability than other eastern Mediterranean records, due to the persistence of tree populations in nearby refugia, allowing a rapid ecological response to abrupt changes in climate (Tzedakis, 2004). Developing an independent chronology for the site to allow the study of these millennial-scale changes, particularly the comparison of their timing and impacts to those identified in other regional records, has proved challenging. These challenges arise from low organic content of the material and older ages associated with radiocarbon dating of sediments from karstic environments, where the underlying geology adds ‘old’, inert carbon to the system. Tephrochronology offers a key means of building age-depth-models for such sites. Here we present the findings of tephrostratigraphic investigations of the 38 metre I-08 core from Lake Ioannina, which spans the last ~50 kyrs BP. Both visible and crypto-tephra horizons have been detected in the core. Geochemical analysis has been used to identify tephra layers associated with explosive volcanism at Italian volcanic sources, including Campi Flegrei, Pantelleria and the Aeolian islands. These tephra horizons provide a chronology for the Ioannina sequence, and facilitate correlations with other key Mediterranean tephrostratigraphic and environmental records such as Lago Grande di Monticchio (Italy), Lake Ohrid (Albania), and Tenaghi Philippon (Greece). 116

P 3.11 in Poster session 3: 28.06.2018, 14:00-

Tephra deposits within the Skaros lava sequence, Santorini, Greece 1 1 RALF GERTISSER , REBECCA WILTSHIRE 1 Keele University, United Kingdom Contact: [email protected]

Santorini, the southernmost volcanic centre of the South Aegean volcanic arc (Greece), is one of the most explosive arc volcanoes in the world. Major explosive activity of Santorini volcano began ~ 360 ka ago. Since then, 12 major (Plinian-style) eruptions and many smaller explosive (interplinian) eruptions [1, 2] occurred, collectively referred to as the Thera Pyroclastic Formation [1]. At least four of the larger Plinian events led to caldera collapse [1, 3]. Monogenetic volcanic centres (cinder cones, tuff rings) and several intracaldera effusive centres, including the Skaros lava shield (~ 67-54 ka), also formed during this period [e.g. 1, 2, 4].

The major Plinian eruptions produced pyroclastic density currents and tephra fallout, the deposits of which form important chronostratigraphic marker horizons in the Eastern Mediterranean marine sedimentary record [e.g. 5-7]. Some tephra layers in marine sediment cores have also been correlated with smaller explosive Santorini eruptions that occurred either between the larger Plinian events or during the evolution of predominantly effusive volcanic edifices, such as the Therasia lava dome complex (~ 39-25 ka) [8].

This paper focuses on the occurrence of tephra deposits associated with explosive volcanic activity of Santorini during the evolution of the Skaros volcano, a mainly basaltic to andesitic lava shield that filled a pre-existing caldera formed by the Middle Tuff eruptions [1, 4]. We recognise a minimum of 8 time intervals with tephra deposits between the nearly 30 lava flows that constitute the Skaros shield. These tephra deposits consist predominantly of scoriaceous (Strombolian) fallout layers and phreatomagmatic tuffs and, rarely, pyroclastic density current deposits that range in thickness from a few centimetres to several metres. They were deposited from single, short-lived and minor explosive events or multiple eruptions that were closely spaced in time. Bulk-rock compositions of juvenile clasts within the tephra deposits vary between ~ 51 and 57 wt. SiO2, which is broadly in line with the compositional range observed in the Skaros lavas (~ 50-58 wt.% SiO2) with the exception of the dacitic Skaros domes (~ 65 wt. % SiO2) that occur at the base of the lava succession.

The occurrence of tephra deposits within the Skaros lava sequence provides evidence of mildly explosive and phreatomagmatic eruptions during constructional intracaldera activity of Santorini. Having originated from the Skaros centre itself or, possibly, from other vents on Santorini, the intra-Skaros tephra layers may provide valuable local stratigraphic markers. Furthermore, some of these previously unidentified tephra layers may well have left a record in the marine realm close to Santorini.

References [1] Druitt, T.H. et al. (1999). Santorini volcano. Geol. Soc. Lond. Mem., 19, 165 pp. [2] Vespa, M. et al. (2006). J. Volcanol. Geothermal. Res, 153, 262-286. [3] Druitt, T.H. & Francaviglia, V. (1992). Bull. Volcanol., 54:484-493. [4] Huijsmans, J.P.P. & Barton, M. (1989). J. Petrol., 30, 583-625. [5] Keller, J. et al. (1978). Geol. Soc. Am. Bull., 89, 591-604. [6] Wulf, S. et al. (2002). Mar. Geol., 183, 131-141. [7] Satow, C. et al. (2015). Quat. Sci. Rev., 117, 96-112. [8] Fabbro, G.N. et al. (2013). Bull. Volcanol., 75, 767. 117

P 3.12 in Poster session 3: 28.06.2018, 14:00-

Using morphological analysis to explain the presence of large grains in distal cryptotephra deposits 1 1 2 1 JENNIFER SAXBY , KATHARINE CASHMAN , FRANCES BECKETT , ALISON RUST 1 School of Earth Sciences, University of Bristol 2 Met Office, UK Contact: [email protected]

Understanding atmospheric ash dispersion has the potential to improve our understanding of cryptotephra deposits. However, numerical dispersion models cannot predict the travel distance of the largest distal cryptotephra shards. Particle shape may act as a major control on cryptotephra dispersion as cryptotephra deposits contain abundant flat, platy shards, interpreted as bubble wall fragments. Irregular particles fall slower and therefore travel further than spheres, yet most dispersion models assume spherical particles. In addition, most dispersion models define particle size as volume-equivalent sphere diameter, while cryptotephra studies report maximum grain lengths; for non-spheres the two measures are not equivalent. We carry out a morphological and grain size analysis of the 12ka BP Vedde ash (Katla volcano, Iceland) which is found throughout northern Europe as a cryptotephra layer. Using consistent size and shape parameters we obtain better agreement between modelled and observed travel distances. By assigning realistic source parameters, we could use dispersion modelling to help constrain potential source regions by providing estimates of maximum potential travel distance for the largest cryptotephra shards found in a site.

P 3.13 in Poster session 3: 28.06.2018, 14:00-

Tephra markers as a tool for the timing of the morphotectonic dynamics in the Campi Flegrei caldera 1 2 2 2 PAOLA PETROSINO , DONATELLA DOMENICA INSINGA , FLAVIA MOLISSO , MARCO SACCHI 1 Dipartimento di Scienze della Terra, dell'Ambienete e delle Risorse, University of Napoli Federico II 2 CNR-IAMC Istituto per l'Ambiente Marino e Costiero Contact: [email protected]

Campi Flegrei volcanic area (southern Italy) is a 12 km wide multiphase caldera hosting part of Napoli city. The nested caldera, a large part of which develops off the Naples (Pozzuoli) Bay, formed as a consequence of two large explosive eruptions, the Campanian Ignimbrite (CI), occurred 39 ka and the Neapolitan Yellow Tuff (NYT), occurred 14.9 ka. The intervals between these main eruptions were punctuated by minor explosive activity from monogenetic centers, located within the caldera. After the NYT eruption the collapsed area, with an 8 km- diameter ring-shaped structure, experienced intervening phases of ground deformation (uplift and subsidence) that summed up their effect to volcanic activity and sediment (mostly volcaniclastic) yields. Hence the shaping of the coastal morphology was strongly affected by the complex interplay between volcano-tectonic deformation, eustatic sea-level changes and volcaniclastic input. In as much, at least 60 low to intermediate size explosive eruptions with vents located on-land and in the submerged part of the caldera emplaced their products in the intracaldera zone, both as primary pyroclastic deposits (density currents and subordinately fallout) and as reworked continental and marine deposits evolved from landslides or lahars and gravity flows.

The present research deals with both primary and reworked deposits embedded into marine sediments in the currently submerged part of the caldera, with the main purpose of refining the chronostratigraphy of tephra deposits of the Pozzuoli Bay to constrain the timing of the 118 post-NYT morphodynamic evolution of the submerged part of the Campi Flegrei caldera. With this aim, a tephrostratigraphic investigation was carried out on a set of marine gravity cores mainly located in the western and central part of the caldera. Sedimentary structures and textures of cored deposits were carefully examined in order to define the primary or reworked nature of the volcaniclastic horizons, including the type of the base of individual layers (sharp or erosive), the grain-size and textural characteristics of the deposit (selected, poorly selected or chaotic) and the origin of the main constituents (mainly juvenile or lithic). The chemical composition of the identified juvenile fractions of the primary deposits was analyzed through SEM-EDS and compared to the available datasets in order to identify the parental explosive events. Among the analyzed tephra, whose sources resulted Campi Flegrei, Somma Vesuvius and Ischia Island, four main markers were identified: 1) the Averno 2 eruption, dated ca. 4.2 ka, with glasses characterized by a typical trachytic composition with Na2O/K2O around 1, 2) the slightly younger Capo Miseno eruption, 3) Astroni 6-7 tephra and 4) the bimodal 79 AD Ischia Cretaio tephra. These well-dated markers were successfully used for chronostratigraphic calibration of very high-resolution, single-channel (Seistec) seismic profiles that support kinematic reconstruction of vertical movements (uplift/subsidence) following the NYT eruption in the Pozzuoli Bay. The results of the tephrostratigraphic analysis of the proximal deposits cored in the Pozzuoli bay also provided new data to support the reconstruction of the dispersal of the products of eruptions characterized by limited outcrops on land (e.g. the Capo Miseno eruption). These issues are of utmost importance for volcanic hazard assessments, since the precise reconstruction of invaded areas and erupted volumes, together with the accurate timing of the ground deformation phases, are of crucial importance for the evaluation of possible effects of a future eruption. Some tephra markers identified in this study can be used for seismic stratigraphic reconstruction both at a local and scale, as they are widely spread also outside the area of the Pozzuoli Bay. Among these, the Capo Miseno tephra has been already identified in the Gaeta Bay and the tephra couplet 79 AD - Ischia Cretaio tephra, is likely a potential marker at 2 ka for the Tyrrhenian Sea.

P 3.14 in Poster session 3: 28.06.2018, 14:00-

Cryptotephra in the Gulf of Taranto (Italy) as time marker for paleoclimatic studies: A combined qualitative and quantitative glass shard analyses 1 2 1 3 VALERIE MENKE , STEFFEN KUTTEROLF , CARINA SIEVERS , JULIE CHRISTIN SCHINDLBECK , 1 GERHARD SCHMIEDL 1 Center for Earth System Research and Sustainability, Institute of Geology, University of Hamburg 2 GEOMAR Helmholtz Centre for Ocean Research Kiel 3 Institute of Earth Sciences, Heidelberg University Contact: [email protected]

Precise age models are of paramount importance for palaeoclimatic and palaeoenvironmental reconstructions based on marine sediment cores. Therefore tephrostratigraphy is an effective dating method since ash layers can be cross-correlated between all types of sedimentary environments including terrestrial, marine and lacustrine archives (e.g. Keller et al., 1978; Kutterolf et al., 2008, 2016; Paterne et al., 1986; Wulf et al., 2004; Neugebauer et al., 2017). Furthermore, in the Mediterranean, tephroanalysis on historical timescales bears minimal uncertainty compared to other common dating methods (AMS 14C dating), since historic documentation exists for major eruptions of the past ∼2000 yrs (Fig. 1 E) (e.g. Arno et al., 1987).

However, in contrast to thick macroscopically identifiable ash deposits from the eastern Mediterranean Area visible tephra layers are absent in the uppermost sediments of this study in the Gulf of Taranto. Nevertheless, dispersed ashes and traces from distal eruptive events may also be traced as cryptotephras in the background sediments. When concentrated in 119 horizons, they can provide valuable insights into eruptive histories as well as significant marker horizons in distal environments where distinct layers are absent.

In this study, we present a combination of continuous microprobe analysis of glass shards together with their respective glass shard abundance within the background sediment from high- resolution stratigraphic samples of the uppermost 45 cm of a sediment core from the Gulf of Taranto (Italy) to evaluate the nature and systematics of the cryptotephra in a semi- quantitative-compositional approach.

The high-resolution quantitative analysis of glass shard abundance in the uppermost 45 cm of the gravity core identified two cryptotephras. Microprobe analysis of glass shards supported by an AMS 14C based age model identified the pronounced primary cryptotephra at 36 cm bsf as the felsic 776 AD Monte Pilato Eruption on the island Lipari, whereas the thinner, mafic tephra layer at 1.5 cm bsf is associated with the 1944 AD eruption of the Somma Vesuvius. Identifying these tephra layers provides an additional, 14C- independent, stratigraphic framework for further palaeoclimatic studies allowing to link Mediterranean climate and hydrology to orbital variation and large scale atmospheric processes. Our results underline the importance of qualitative tephrostratigraphy in a highly geodynamic region, where solely quantitative approaches have demonstrated to bear a high potential for false correlations between tephra layers and eruptions. The combination of qualitative and quantitative glass shard analyses allows for a reliable correlation of tephra layer(s) to eruptions in this region.

P 3.15 in Poster session 3: 28.06.2018, 14:00-

Combined marine, lacustrine, and terrestrial tephrachronostratigraphy of Central America and its implications for volcanology and geology 1 2 STEFFEN KUTTEROLF , JULIE CHRISTIN SCHINDLBECK 1 GEOMAR Helmholtz Centre for Ocean Research Kiel 2 Institute of Earth Sciences, University of Heidelberg Contact: [email protected]

The Central American convergent margin, characterized by the Cocos plate subducting beneath the Caribbean plate, is a part of the Pacific “Ring of Fire” where explosive volcanism occurs frequently in addition to also frequent earthquakes. Studying the processes that control eruption recurrence times, cyclicities in the volcanic record, and seismogenesis of an erosive subduction zone are therefore a strong motivation to understand the natural hazards represented by volcanoes and earthquakes in these regions. Although obviously large explosive eruptions from Costa Rica, Nicaragua, Honduras, El Salvador and Guatemala happened in the past, the information and data regarding their wider distribution and the former volcanic activity are very sparse and cannot be studied continuously with field data alone.

In the last decade we investigated marine and lacustrine sediments cored by German research vessel, drilled by the International Continental Scientific Drilling Program (ICDP) and the Integrated Ocean Drilling Program (IODP), as well as the older Ocean and Deep See Drilling Program along the Central American Volcanic Arc (CAVA). For provenance analyses the recovered tephras (~3300) were compared with data from literature but also data from samples collected during own field campaigns (1000 samples).

The comprehensive data set of these marine and lacustrine cores revealed a unique, most complete tephrochronostratigraphic compilation for the whole CAVA that reaches back to at least the middle Miocene, covering an area of up to 106km2in both, the Pacific Ocean and the Caribbean Sea. Using direct geochemical fingerprinting as well as the systematic along-arc 120 variations of trace-element characteristics from terrestrial studies we have been able to identify ~320 individual eruptions that have been assigned to source areas on land, including 73 correlations to specific eruptions as well as another 70 widely distributed tephra layers for which their specific region of origin along the CAVA has been constrained. Tephra layer correlations to independently dated terrestrial deposits provide new time markers and help to improve or confirm age models of the respective drill sites and enabled us to calculate average accumulation rates of pelagic sediments that range from 0.5–20 cm/ka on the incoming plate to >1000 cm/ka on the continental slope. Applying the respective sedimentation rates derived from the age models, we calculated ages for all marine ash beds. Hence, we also obtained new age estimates for 24 known, but so far undated large terrestrial eruptions.

Source regions of the tephra layers recovered during the IODP Expeditions are predominately the volcanic arcs in Costa Rica, Nicaragua, El Salvador, Honduras, Guatemala and accessory Mexico, as well as a portion of ~220 marine tephras (~8 Ma to ~16.5 Ma) with two-thirds of the ash beds being of mafic (<57 wt% SiO2) compositions, that is clearly associated with the Galápagos archipelago. The temporal distribution of these tephra layers reveals a distinct increase in eruption frequency and hence increased volcanic activity of the Galápagos hotspot after 14 Ma associated to variable magma production rates due to changes in plume-ridge interactions.

The tephrochronostratigraphy and provenance further allowed us to extend the paleoclimate record in Central America investigating ICDP drill cores of Lake Petén Itzá in the Neotropical lowlands of northern Guatemala to 400 ka, to constrain the arrival of the Cocos Ridge at the Costa Rican margin to 2.9 Ma, to recognize the existence of long-living magmatic systems at the CAVA, to extend the eruptive history of individual volcanic complexes far back in time, to constrain temporal and compositional shifts along the CAVA, to calculate long-term erupted magma fluxes along the arc, and to constrain the behavior and ages of fluid venting and slope failures at the slope.

P 3.16 in Poster session 3: 28.06.2018, 14:00-

Multi-method luminescence dating of soil formation events in Last Glacial east European loess 1 1 2 3 VIORICA TECSA , DANIEL VERES , NATALIA GERASIMENKO , CHRISTIAN ZEEDEN , ULRICH 4 1 HAMBACH , ALIDA TIMAR-GABOR 1 Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Cluj- Napoca, Romania 2 Taras Shevshenko National University, Kiev, Ukraine 3 IMCCE,Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ Paris, Univ Lille, Paris, France 4 BayCEER & Chair of Geomorphology, University of Bayreuth, Bayreuth, Germany Contact: [email protected]

Deriving reliable age control for loess-paleosol sequences is pre-requisite to exploring the potential of such paleoenvironmental arhives in providing high-resolution records of past climate change. In our current study we provide a robust luminescence chronology for Stayky (Ukraine), a reference profile in European Late Pleistocene loess stratigraphy that has been previously investigated by Rousseau et al. (2011) [1] using infrared stimulated luminescence dating (IRSL) on only four samples. In order to obtain a high resolution chronology, 15 new samples coded STY, considered as representative for the Stayky loess-paleosol sequence, have been additionally subjected to luminescence dating investigations. Dating has been carried out using the single-aliquot regenerative dose (SAR) protocol ondifferent grain sized quartz (4-11 µm, 63-90 µm), alongside IRSL (namely post infrared-infrared stimulated luminescence (pIR-IRSL290)) on polymineral fine grains. For the Bug loess unit, the 121 equivalent of Marine Isotope Stage (MIS 2), the dating results are in agreement between methods, demonstrating that the suite of embryonic soils previously interpreted as reflecting climate variability similar to Greenland interstadials (GI) actually date to ~29/27-15 ka, with most emplaced around or after 20 ka. The dating of samples roughly bracketing the Vytachiv paleosol, previously debatably linked to various GI events within MIS 3 resulted in ages of 40.1±3.7 ka (4-11 µm quartz), 39.6±3.5 ka (63-90 µm quartz) and 53.2±4.6 ka (pIR-IRSL290) at the lower transition, and 25.0±2.1 ka (4-11 µm quartz), 27.2±2.2 ka (63-90 µm quartz) and 29.5±2.4 ka (pIR-IRSL290) in the overlying loess. These ages indicate that the truncated Vytachiv paleosol as preserved at Stayky extends over middle-to-late MIS 3. The pIR-IRSL290 dating of the loams immediately underneath Pryluky unit in the range of 133±13 ka or 154±14 ka depending on the water content used, and of the Prylukymollisol from 99.6±9.2 ka to 115±11 ka confirm the broad correspondence of this unit with MIS 5, while quartz results severely underestimate these ages. The application of pIR-IRSL290 dating for the underlying Dnieper till believed to have been emplaced during the Saalian glaciation resulted in natural signals at the level of laboratory saturation. This is evidence that pIR-IRSL290 is not affected by anomalous fading; however, based on the available data, ages as old as >700 ka could be expected. For the same sample, the natural SAR-OSL signals for 4-11 µm quartz have been found significantly below laboratory saturation level, resulting in finite ages of ~250-270 ka, while coarse quartz (63-90 µm) signals reached about 85% of the laboratory saturation level. These data suggest extreme caution must be taken when dating such old samples using quartz OSL. Results from our high-resolution luminescence dating raises important implications for the chronological representativeness of Stayky as a key loess site in eastern Europe beyond MIS 2.

References: 1. Rousseau, D. D., Antoine, P., Gerasimenko, N., Sima, A., Fuchs, M., Hatte, C., Moine, C. and Zoeller, L., 2011. North Atlantic abrupt climatic events of the last glacial period recorded in Ukrainian loess deposits. Climate of the Past, 7, 221-234.

Acknowledgement: The authors acknowledge the financial support from PN-III-P3-3.6- H2020-2016-0016, contract 7/2016.

P 3.17 in Poster session 3: 28.06.2018, 14:00-

Multi-methods luminescence dating of the Batajnica loess section in south of the Carpathian Basin 1 1 2 1 3 ANCA AVRAM , DANIELA CONSTANTIN , DANIEL VERES , SZABOLCS KELEMEN , IGOR OBREHT , 4 5 1 ULRICH HAMBACH , SLOBODAN MARKOVIĆ , ALIDA TIMAR-GABOR 1 Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, Cluj- Napoca, Romania 2 Romanian Academy, Institute of Speleology, Cluj-Napoca, Romania 3 Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Bremen, Germany 4 Chair of Geomorphology, Geosciences, University of Bayreuth, Bayreuth, Germany 5 Chair of Physical Geography, Faculty of Sciences, University of Novi Sad, Serbia Contact: [email protected]

Loess sequences in the Northern Serbia provide one of the most important terrestrial records of past climate changes in Europe during the Middle and Late Pleistocene. The Batajnica section is among the most significant loess-paleosol sequences in the region, with a thickness of 40 m. The site has been previously investigated for stratigraphy, geochemistry and magnetic susceptibility. The profile comprises 6 major pedocomplexes and 6 weakly developed interstadial soils with the whole sequence reaching to Marine Isotope Stage (MIS) 15 [1]. Notably, two visible albeit strongly altered tephra layers have been identified in the L2 loess, roughly equivalent to MIS 6. 122

However, so far, no in depth state of the art absolute dating of the Batajnica section has been carried out, with only a TL chronology being presented [2]. In order to establish a luminescence chronology for this site, 23 samples have been dated using luminescence methods. The optically stimulated luminescence (OSL) dating was performed by applying the single aliquot regenerative (SAR) protocol on fine (4-11 µm) and respectively coarse (63-90 µm) quartz extracted from loess samples. The luminescence characteristics of both fine and coarse quartz grains indicate that apparently the SAR-OSL protocol is suitable for dating the samples. Preliminary age results on coarse (63-90 µm) quartz extracts range from 9.4 ± 0.7 ka for a sample taken just below the Holocene soil to about 150 ka for samples collected from L2, L3 and L4 units. In this age range, OSL signal from quartz seems to display field saturation. An age of 38.5 ± 3.0 ka was obtained for the loess sample collected just above a potential tephra layer in the uppermost loess unit (L1), that very likely correlates with the Campanian Ignimbrite/Y5-ash layer, the latter with a widespread occurrence in the Danube basin [3]. The preliminary luminescence dating results further confirm the grain-size dependent discrepancy previously reported for ages as well as equivalent doses for loess samples of different origins [4]. Ages of 117± 14 ka and 83 ± 7 ka have been obtained on coarse and fine grains respectively for the loess sample collected above the upper tephra layer identified in the L2 loess. In order to check the reliability of the OSL ages, further post- IR IRSL290 dating on polymineral fine grains is in progress.

References 1. Marković, S.B., Hambach, U., Catto, N., Jovanović, M., Buggle, B., Machalett, B., Zöller, L., Glaser, B., Frechen, M., 2009, Middle and Late Pleistocene loess sequences at Batajnica, Vojvodina, Serbia, Quaternary International 198 (2009) 255-266. 2. Butrym, J., Maruszcak, H., Zeremski, M., 1991. Thermoluminescence stratigraphy of Danubian loess in Belgrade environs. Annales, Universite Marie-Curie Sklodowska, B 46, 53-64. 3. Veres, D., Lane, C.S., Timar-Gabor, A., Hambach, U., Constantin, D., Szakács A., Fülling, A., Onac, B.P., The Campanian Ignimbrite/Y5 tephra layer – A regional stratigraphic marker for Isotope Stage 3 deposits in the Lower Danube region, Romania, Quaternary International 293 (2013) 22-33. 4. Timar-Gabor A., Buylaert J.P., Guralnik B., Trandafir-Antohi O., Constantin D., Anechitei-Deacu V., Jain M., Murray A.S., Porat N., Hao Q., Wintle A.G., in press. On the importance of grain size in luminescence dating using quartz, Radiation Measurements 106 (2017) 464-471

Acknowledgement: The authors acknowledge the financial support from PN-III-P3-3.6- H2020-2016-0016, contract 7/2016.

P 3.18 in Poster session 3: 28.06.2018, 14:00-

Revisiting the chronology of Mircea Vodă loess-paleosol sequence, Romania 1 1 2 ȘTEFANA MĂDĂLINA GROZA , DANIELA CONSTANTIN , CRISTIAN GEORGE PANAIOTU , RAMONA 3 1 BĂLC , TIMAR-GABOR ALIDA 1 Interdisciplinary Research Institute on Bio-Nano-Sciences,Babes-Bolyai University, Cluj- Napoca, Romania 2 Faculty of Physics, University of Bucharest, Bucharest, Romania 3 Faculty of Environmental Sciences and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania Contact: [email protected]

Situated in the Dobrogea region, in the proximity of the Danube River and the Black Sea, the loess-paleosol archive from Mircea Vodă represents one of the most studied sections in Eastern Europe. The approximately 26 m thick aeolian deposit comprises six well developed pedocomplexes, thus covering the last 17 Marine Isotope Stages (MIS). Previous sedimentological, geochemical and environmental magnetic results showed that the loess from Mircea Vodă displays similarities with the loess from the Vojvodina sections, with the 123 sediment budget being attributed to the Danube River. An additional input from the Ukrainian glaciofluvial deposits and local sand dune fields was also proposed [1].

Mircea Vodă was the first section in Romania to be dated using luminescence methods based on quartz extracts [2][3]. The quartz luminescence studies focused on the last four glacial periods, with 9 samples being taken from the uppermost loess layer (L1) and three more from L2, L3 and L4 loess units, respectively. Optically stimulated luminescence (OSL) was used on fine silt-sized (4-11 µm) [2] and fine sand-sized (63-90 µm) quartz [3] extracts by applying the single aliquot regenerative (SAR) protocol. The ages obtained ranged from 8.7 ± 1.3 to 159 ± 24 ka for fine silt-sized (4-11 µm) quartz and from 16 ± 2 ka to 230 ± 31 ka for fine sand-sized (63-90 µm) quartz. The results raised one significant issue that has not been yet fully addressed – why would the two quartz fractions yield different age results despite their similar OSL characteristics and behaviour? Further uncorrected ages using post-IR IRSL225 protocol on polymineral fine (4-11 µm) grains extracted from the same samples supported the fine silt-sized (4-11 µm) quartz OSL ages from L1 and L2 units and the sand-sized (63-90 µm) ages for the older L3 and L4 units [4].

The aim of the current study is to improve the existing chronology by revisiting the loess- paleosol sequence from Mircea Vodă. In that respect, a total of 14 new samples have been taken from the profile for OSL dating and magnetic susceptibility analysis, from which 6 samples from the S0/L1 limit and doublets for the L2, L3, L5 and L5 loess units, samples being collected just below the palaeosols. Investigations on fine silt-sized (4-11 µm) and fine sand-sized (63-90 µm) quartz extracts as well as polymineral fine grains are in progress. Knowing that the post-IR IRSL225 protocol, unlike post-IR IRSL290, may suffer from fading, we will complement the investigations by performing post-IR IRSL290 measurements and all the results will be presented.

References 1. Buggle, B., Glaser, B., Zöller, L., Hambach, U., Marcović, S., Glaser, I., Gerasimenko, N., 2008. Gechemical characterization and origin of the Southeastern and Eastern European loesses (Serbia,Romania, Ukraine), Quaternary Science Reviews, 27, 1058-1075. 2. Timar, A., Vandenberghe, D., Panaiotu, E.C., Panaiotu, C.G., Necula, C., Cosma, C., van den haute, P., 2010. Optical dating loess using fine-grained quartz, Quaternary International, 5, 143-148. 3. Timar-Gabor, A., Vandenberghe, D.A.G, Vaasiliniuc, S., Panaiotu, C.E., Panaiotu, C.G., Dimofte, D., Cosma, C., 2011. Optical dating of Roamanian loess: A comparison between silt-sized and sand- sized quartz, Quaternary International, 240, 62-70. 4. Vasiliniuc, S., Vandenberghe, D.A.G., Timar-Gabor, A., Panaiotu, C., Cosma, C. 2012. Testing the potential of elevated temperature post-IR IRSL signals for dating Romanian loess, Quaternary Geochronology, 10, 75-80.

Acknowledgement: The authors acknowledge the financial support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme ERC-2015-STG (grant agreement No [678106]).

124

List of Participants

A Abbott, Peter, [email protected], University of Bern, Institute of Geological Sciences: O 1.1, P 2.14 Avram, Anca, [email protected], Babes-Bolyai University: P 3.17 B Baykal, Yunus, [email protected], University of Bayreuth, Chair of Geomorphology: P 1.17 Belo, Mathis, [email protected], University of Heidelberg: P 3.14, P 3.15 Blaauw, Maarten, [email protected], Queen's University Belfast, School of Natural and Built Environment: Keynote 4 Bösken, Janina, [email protected], RWTH Aachen University, Department of Physical Geography and Geoecology, Geographical Institute: O 4.2 Botezatu, Akos, [email protected], University of Bayreuth Bourne, Anna, [email protected], University of Southampton, Geography and Environment: O 1.2, P 1.15 Bouvet de Maisonneuve, Caroline, [email protected], Nanyang Technological University, Asian School of the Environment: Keynote 6 Bowen, Eva Angelina, [email protected], University of Portsmouth, Department of Geography Buckland, Hannah, [email protected], University of Bristol, School of Earth Sciences: O 7.5 C Campisano, Chris, [email protected], Arizona State University, Institute of Human Origins Cashman, Katharine, [email protected], University of Bristol, School of Earth Sciences: O 7.4 Constantin, Daniela, [email protected], Babes-Bolyai University, Interdisciplinary Research Institute in Bio-Nano-Sciences: P 2.2 Cutler, Nick, [email protected], Newcastle University, School of Geography, Politics & Sociology: P 1.1, P 1.2 D Davies, Lauren, [email protected], University of Alberta, University of Alberta: O 4.6, P 1.12 Dugmore, Andrew, [email protected], University of Edinburgh, School of GeoSciences: O 3.1, P 1.14 F Foster, Anne, [email protected], Presbyterian Medical Fu, Yu, [email protected], Institute of Geology and Geophysics, Chinese Academy of Sciences, Key Laboratory of Cenozoic Geology and Environment: O 5.5 G Gehrels, Maria, [email protected], University of York, Environment Department: P 2.5 Gencalioglu Kuscu, Gonca, [email protected], Mugla Sitki Kocman University, Department of Geological Engineering: O 4.1 Gertisser, Ralf, [email protected], Keele University: P 3.11 Groza, Stefana Madalina, [email protected], Babes-Bolyai University: P 3.18 Gudmundsdóttir, Esther Ruth, [email protected], Institute of Earth Sciences, University of Iceland: O 1.5, P 1.10 H 125

Haliuc, Aritina, [email protected], Research Institute of the University of Bucharest: P 2.3 Hambach, Ulrich, [email protected], University of Bayreuth, BayCEER & Chair of Geomorphology Harangi, Szabolcs, [email protected], MTA-ELTE Volcanology Research Group and Department of Petrology and Geochemistry, Eötvös University: O 5.2 Hirniak, Jayde, [email protected], ASU, Institute of Human Origins, School of Human Evolution and Social Change: P 3.8 Hopkins, Jenni, [email protected], Victoria University of Wellington, School of Geography Environment and Earth Sciences: O 7.1, P 2.11 Huang, Yu-Tuan (Doreen), [email protected], Umeå University, Department of Ecology and Environmental Science: O 3.3 I Insinga, Donatella, [email protected], CNR-Italy, IAMC: P 3.9 J Jensen, Britta, [email protected], University of Alberta, Earth and Atmospheric Sciences: O 6.4, P 1.13 Jones, Gwydion, [email protected], Swansea University, Geography: P 1.3 K Karátson, Dávid, [email protected], Eötvös University, Budapest, Dept. Physical Geography: Keynote 5 Kearney, Rebecca, [email protected], University of Oxford, RLAHA: O 5.4 Kuehn, Stephen, [email protected], Concord University, Physical Science: P 2.9, P 2.10 Kuscu, Zeynep Duru, [email protected], Mugla Sitki Kocman University, Mugla Sitki Kocman University Kyle, Philip, [email protected], New Mexico Tech, Earth & Environmental Science: P 1.7 L Laag, Christian, [email protected], University of Bayreuth, Chair of Geomorphology: P 3.6 Larsson, Simon, [email protected], Stockholm University, Department of Physical Geography: O 1.3 Lehmkuhl, Frank, [email protected], RWTH Aachen University, Department of Geography: O 2.1 Leicher, Niklas, [email protected], University of Cologne, Institute of Geology and Mineralogy: O 5.6, P 1.4 Loame, Remedy, [email protected], University of Waikato, School of Science: O 3.4, P 2.6 Longman, Jack, [email protected], University of Southampton, School of Ocean and Earth Sciences: O 3.6 Lowe, David, [email protected], University of Waikato, School of Science (Earth Sciences): O 3.2, P 2.7, P 2.8 Lukács, Réka, [email protected], MTA-ELTE Volcanology Research Group: O 5.3 M Magyari, Enikő, [email protected], Eötvös Loránd University, Department of Environmental and Landscape Geography, Research group of Paleontology: O 5.1 Markovic, Rastko, [email protected], University of Novi Sad, Department of Physical Geography Markovic, Slobodan, [email protected], University of Novi Sad, Department of Physical Geography Martin-Jones, Catherine, [email protected], Cambridge University, Geography: O 6.5, P 2.13 McGuire, Amy, [email protected], University of Cambridge, Geography: P 3.10 Miyabuchi, Yasuo, [email protected], Kumamoto University, Faculty of Advanced Science and Technology: P 2.1 Moles, Jonathan, [email protected], The Open University, School of Environment, Earth and Ecosystem Sciences: O 7.3 Monteath, Ali, [email protected], University of Southampton: O 2.4 O Oalmann, Jeffrey, [email protected], 126

Nanyang Technological University, Singapore, Earth Observatory of Singapore: O 4.4 Oesterle, Pierre, [email protected], University of Umeå Okuno, Mitsuru, [email protected], Fukuoka University, Department of Earth System Science: P 1.16 Óladóttir, Bergrún Arna, [email protected], Institute of Earth Sciences, University of Iceland: P 1.8, P 1.9 P Pearce, Nicholas, [email protected], Aberystwyth University, Department of Geography and Earth Sciences: O 7.2, P 2.15 Peti, Leonie, [email protected], University of Auckland, School of Environment: O 3.5 Petrosino, Paola, [email protected], University of Napoli Federico II, Dipartimento di Scienze della Terra, dell'Ambienete e delle Risorse: P 3.13 Phua, Marcus, [email protected], Nanyang Technological University, Singapore, Asian School of the Environment & Earth Observatory of Singapore: O 6.1 Plunkett, Gill, [email protected], Queen's University Belfast, Archaeology & Palaeoecology Ponomareva, Vera, [email protected], Institute of Volcanology and Seismology: Keynote 2 Pötter, Stephan, [email protected], RWTH Aachen University, Department of Geography: P 3.7 Pyne-O'Donnell, Sean, [email protected], Independent: O 1.4 R Radakovic, Milica, [email protected], University of Novi Sad, Department of Physical Geography: P 3.2 Rust, Alison, [email protected], University of Bristol, Earth Sciences: O 7.6 S Saxby, Jennifer, [email protected], University of Bristol, School of Earth Sciences: P 3.12 Schindlbeck, Julie Christin, [email protected], University of Heidelberg, Institute of Earth Sciences: O 2.6, P 2.4 Schmidt, Christoph, [email protected], University of Bayreuth, Chair of Geomorphology: O 4.3 Seghedi, Ioan, [email protected], Institute of Geodynamics, Romanian Academy: Public Lecture Sigl, Michael, [email protected], Universtiy of Oslo, Department of Geosciences: Keynote 3 Singh, Ajab, [email protected], SGB Amravati University, Amravati, India, Department of Geology: O 6.3 Sirocko, Frank, [email protected], University Mainz, Institute for Geoscience: O 1.6 Sławińska, Joanna, [email protected], University of Szczecin, Geology and Palaeogeography Unit Srivastava, Ashok K., [email protected], SGB Amravati University, Geology: P 2.16 Streeter, Richard, [email protected], University of St Andrews, School of Geography and Sustainable Development: P 1.5, P 3.5 Sun, Chunqing, [email protected], Institute of Geology and Geophysics, Chinese Academy of Sciences: O 2.5 Suzuki, Takehiko, [email protected], Tokyo Metropolitan University, Department of Geography: O 6.2, P 2.12 T Tecsa, Viorica, [email protected], Babes-Bolyai University: P 3.16 Timms, Rhys, [email protected], Royal Holloway, University of London, Geography: P 3.1 Torii, Masayuki, [email protected], Kumamoto University: P 1.11 V Vakhrameeva, Polina, [email protected], Heidelberg University, Institute of Earth Sciences: O 2.2 van den Bogaard, Christel, [email protected], GEOMAR Helmholtz Centre for Ocean Research Kiel: P 1.6 Veres, Daniel, [email protected], Romanian Academy: P 3.3, P 3.4 Vidal, Celine, [email protected], University of Cambridge, Department of Geography: O 6.6 W 127

Wastegård, Stefan, [email protected], Stockholm University: O 2.3 Westgate, Cora, [email protected], University of Toronto, Earth Sciences Westgate, John, [email protected], University of Toronto, Earth Sciences: Keynote 7 Wulf, Sabine, [email protected], University of Portsmouth, Department of Geography: Keynote 1 Z Zawalna-Geer, Aleksandra, [email protected], University of Exeter, Camborne School of Mines: P 2.17 Zelenin, Egor, [email protected], Geological Institute: O 4.5

128

List of Authors

A Marković, Slobodan B.: P 3.2, P 1.17, O 4.2, Abbott, Peter: O 1.1, O 1.2, O 7.3, P 2.14 O 5.5, P 2.2, P 3.7, P 3.17, P 3.3, P 3.4, P 3.6 Adler, Daniel: P 3.1 Marple, Joseph: P 1.2 Albert, Paul: O 5.4, P 3.10, O 5.6 Martin-Jones, Catherine: O 6.5, P 2.13 Alida, Timar-Gabor: P 3.18 Maruyama, Seiji: O 6.2 Alloway, Brent: O 7.2 Mason, Paul R.D.: O 5.2 Amesbury, Matt J: P 2.8 McConnell, Joseph R.: Keynote 3 Anechitei-Deacu, Valentina: P 2.2, P 3.4 McGarvie, Dave: O 7.3 Aoki, Kaori: P 2.12 McGee, Lucy: O 7.1 Appelt, Oona: O 2.2 McGovern, Tom: P 3.5 Appleby, Peter: O 4.6 McGuire, Amy: P 3.10 Arai, Fusao: O 6.2 McManus, Jerry: O 2.6 Ariztegui, Daniel: P 1.4 McNamara, Keri: O 7.6 Asrat, Asfawossen: O 6.5 Menke, Valerie: P 3.14 Augustinus, Paul: O 3.5, P 2.5, P 2.17 Miggins, Dan: O 4.1 Avram, Anca: P 3.17 Miller, Christopher E.: P 3.8 B Millet, Marc-Alban: O 7.1 Bachmann, Olivier: O 5.3 Miyabuchi, Yasuo: P 2.1 Bălc, Ramona: P 3.18 Mleneck-Vautravers, Maryline: O 2.6 Barfod, Dan: O 6.6 Mohr, Paul: O 6.6 Barker, Phil: P 2.13 Moles, Jonathan: O 7.3 Barker, Steve: P 2.14 Molisso, Flavia: P 3.13 Barsotti, Sara: P 1.9 Molnár, Kata: O 5.2 Baykal, Yunus: P 1.17, P 3.6 Molnár, Mihály: O 5.2 Bazanova, Lilia: Keynote 2 Monteath, Alistair: O 2.4, O 6.4 Beckett, Frances: P 3.12 Moon, Vicki G.: O 3.2, P 2.6 Begy, Robert Csaba: P 2.2 Moussallam, Yves: O 6.6 Benazzi, Stefano: P 3.8 Mullan-Boudreau, Gillian: O 4.6 Benkó, Zsolt: O 5.3 Myrbo, Amy: P 2.9 Bergal-Kuvikas, Olga: Keynote 6 N Björck, Svante: O 1.5 Nakamura, Toshio: P 1.16 Blaauw, Maarten: Keynote 4, P 2.13 Nakayama, Daichi: P 2.12 Blockley, Simon: P 3.1 Negrino, Fabio: P 3.8 Booth, Robert: O 6.4 Neugebauer, Ina: P 2.3 Bösken, Janina: O 4.2, P 3.3, P 3.4, P 3.6, P 3.7 Newnham, Rewi M.: P 2.5, P 2.8 Botezatu, Akos: P 3.6 Newton, Anthony: O 3.1, P 1.14, P 3.5 Bourne, Anna: O 1.1, O 1.2, P 1.15 Niespolo, Elizabeth: P 1.4 Bouvet de Maisonneuve, Caroline: Keynote 6, Nishiyama, Ken-ichi: P 1.11 O 4.4 Nishizawa, Fumikatsu: P 2.12 Bradley, Kyle: Keynote 6 Noernberg, Tommy: O 4.6 Brauer, Achim: Keynote 1, P 2.3 Nolan, Connor: O 6.4 Brill, Dominik: O 4.2 Nomade, Sebastien: O 5.6, P 1.4 Brin, Adam: P 3.5 Noren, Anders: P 2.9 Brown, Maxwell: O 6.5 Novothny, Ágnes: Keynote 5, O 5.2 Bubenshchikova, Natalia: Keynote 2, O 4.5 Ntaflos, Theodoros: O 5.2 Buckland, Hannah: O 7.5 O Buczkó, Krisztina: O 5.1 Oalmann, Jeffrey: Keynote 6, O 4.4 Buret, Yannick: O 5.3 Obreht, Igor: O 4.2, P 1.17, P 3.2, P 3.3, P 3.4, Burow, Christoph: O 4.2 P 3.6, P 3.7, P 3.17 Buylaert, Jan-Pieter: P 2.2 Oddsson, Björn: P 1.9 C Ojima, Tomoko: O 6.2 Calvo, Alfonso Benito: O 6.6 Okuno, Mitsuru: P 1.11, P 1.16 Cameron, Cheryl: P 2.9 Óladóttir, Bergrún Arna: P 1.8, P 1.9, P 1.10 Cashman, Katharine: O 7.4, O 7.5, O 7.6, P 3.12 Opitz, Rachel: P 3.5 129

Charman, Dan J: P 2.8 Oppenheimer, Clive: O 6.6 Christopher, Bronk Ramsey: O 5.4 Orense, Rolando: O 3.2 Churchman, G. Jock: O 3.3 Oross, Rebeka: O 5.2 Cisneros de León, Alejandro: P 2.4 Orpin, Alan: P 2.11 Collins, James: Keynote 1 Orr, Caley: P 3.8 Constantin, Daniela: P 2.2, P 3.17, P 3.18 P Cooper, Alan: O 3.3 Pagneux, Emmanuel: P 1.9 Cormier, Marc-André: Keynote 1 Palmer, Martin: O 3.6 Cursons, Ray: O 3.3 Panaiotu, Cristian: P 2.2, P 3.18 Cutler, Nick: O 3.1, P 1.1, P 1.2, P 1.5 Pearce, N.J.G.: O 7.2, P 2.15, O 6.5, P 2.7, P 1.6 D Pécskay, Zoltán: Public Lecture Danhara, Tohru: O 6.2 Pereira, Alison: P 1.4 Daniel, Veres: O 5.4 Peresani, Marco: P 3.8 Danišík, Martin: O 4.1 Peric, Zoran: P 1.17 Davies, Lauren: O 4.6, O 6.4, P 1.12 Peti, Leonie: O 3.5 Davies, Sarah: P 1.3, P 2.17 Petrosino, Paola: P 3.9, P 3.13 Davies, Siwan: O 1.1, O 1.2, P 1.3, P 2.17, O 3.2, Pfaender, Jörg: O 5.3 O 3.4, P 2.6 Phua, Marcus: Keynote 6, O 4.4, O 6.1 de Lange, Gert J.: P 3.9 Pittari, Adrian: O 3.4, P 2.6 de Lange, Willem P.: O 3.2, P 2.6 Plechova, Anastasia: Keynote 2 de Maisonneuve, Caroline Bouvet: O 6.1 Plunkett, Gill: Keynote 3, O 6.4 Derkachev, Alexander: Keynote 2, O 4.5 Ponomareva, Vera: Keynote 2, O 4.5, P 1.6 Dibacto, Stéphane: Keynote 5 Portnyagin, Maxim: Keynote 2, O 4.5 Dugmore, Andrew: O 3.1, P 1.1, P 1.2, P 1.5, Portnyagin, M.V.: P 1.6 P 1.14, P 3.5 Pötter, Stephan: O 4.2, P 3.4, P 3.7 Dunkl, István: O 5.2, O 5.3 Preece, Katie: P 3.1 E Pross, Jörg: O 2.2 Eiríksson, Jón: O 1.5 Putra, Rizaldi: Keynote 6 Eisele, Steffen: Keynote 6 Pyne-O'Donnell, Sean: O 1.4, O 6.4 Engels, Stefan: P 2.3 Q Engwell, Samantha: O 7.5 Qingzhen, Hao: P 3.2 Enikő, Magyari: O 5.4 R Evans, Elizabeth: P 2.6 Radaković, Milica G.: P 3.2, P 3.3, P 3.6 F Rawlence, Nicolas J.: O 3.3 Fils, Douglas: P 2.9 Razali, Nur Fairuz: Keynote 6 Finsinger, Walter: O 5.1 Rees, Andrew B.H.: O 3.2, P 2.8, O 3.4, P 2.6 Fitch, Shelby: P 3.8 Regattieri, Elenora: P 1.4 Fletcher, William J.: O 2.2 Ren, Minghua: P 3.8 Florindo, Fabio: P 1.4 Renne, Paul: P 1.4 Fontijn, Karen: O 6.6 Riel-Salvatore, Julien: P 3.8 Forni, Francesca: Keynote 6 Rifai, Hamdi: O 6.1 Förster, Michael: O 1.6 Rogozin, Alexey: Keynote 2 Francke, Alexander: O 5.6 Ross, Nic: O 3.2, O 3.4, P 2.6 Frank, Ute: O 6.5 Roucoux, Katy: P 3.10 Freundt, Armin: O 2.6 Rust, Alison: O 7.4, O 7.5, O 7.6, P 3.12 Froese, D.G.: P 1.6 Sacchi, Marco: P 3.13 Froese, Duane: O 4.6, P 1.12 S Fu, Yu: O 5.5 Sachse, Dirk: Keynote 1, P 2.3 G Saxby, Jennifer: O 7.4, P 3.12 Gadd, Patricia: O 3.5 Scaife, Rob: O 2.4 Gaeta, Mario: P 1.4 Schaebitz, Frank: O 6.5 Gatti, Emma: P 2.15 Schindlbeck, Julie Christin: O 2.6, P 2.4, P 3.14, Gavrilov, Milivoj: P 3.2 P 3.15 Gehrels, Maria: P 2.5, P 2.8 Schipper, Louis A.: O 3.3 Gencalioglu Kuscu, Gonca: O 4.1 Schmidt, Christoph: O 4.3 Gerasimenko, Natalia: P 2.2, P 3.16 Schmiedl, Gerhard: P 3.14 Gernon, Thomas: O 3.6 Schmitt, Axel K.: O 5.2, P 2.4 130

Gertisser, Ralf: Keynote 5, P 3.11 Schönwetter, Thomas: P 3.6 Giaccio, Biagio: O 5.6, P 1.4 Schulte, Philipp: P 1.17 Goring, Simon: P 2.9 Schwab, Markus J.: Keynote 1 Gottschalk, Julia: P 2.14 Sear, David: P 1.15 Gravel-Miguel, Claudine: P 3.8 Sebe, Krisztina: O 5.3 Griggs, Adam: O 1.1 Seghedi, Ioan: O 5.2, Public Lecture Groza, Ștefana Mădălina: P 2.2, P 3.18 Sherlock, Sarah: O 7.3 Gualda, Guilherme: P 2.15 Sherriff, Jenni: P 3.1 Gudmundsdóttir, Esther Ruth: O 1.5, P 1.10 Shotter, Lauren: P 1.2 Guðmundsson, Magnús: P 1.9 Shotyk, William: O 4.6 Guillong, Marcel: O 5.3 Sievers, Carina: P 3.14 Guo, Zhengtang: O 5.5 Sigl, Michael: Keynote 3 H Sigmarsson, Olgeir: P 1.8, P 1.10 Haliuc, Aritina: P 2.3 Singh, Ajab: O 6.3, P 2.16 Halton, Alison: O 7.3 Singh, Satish: O 6.1 Hambach, Ulrich: O 4.2, P 1.17, P 2.2, P 3.3, Sirocko, Frank: O 1.6 P 3.4, P 3.6, P 3.7, P 3.16, P 3.17, P 3.2 Skinner, Luke: P 2.14 Hamdi, Rifai: Keynote 6 Sliwinski, Jakub: O 5.3 Hao, Qingzhen: O 5.5 Smith, Euan: O 7.1 Harangi, Szabolcs: O 5.2, O 5.3 Smith, Eugene: P 3.8 Harijoko, Agung: P 1.16 Smith, Ian: O 7.1 Hasenaka, Toshiaki: P 1.11 Smith, Victoria: O 6.5 Hayward, Chris L: P 2.7 Soós, Ildikó: O 5.3 Hazell, Zoë J: P 2.8 Srivastava, Ashok K.: P 2.16 Hirata, Takafumi: O 6.2 Staff, Richard: O 5.4 Hirniak, Jayde: P 3.8 Stevenson, John: O 7.3 Hodgkins, Jamie: P 3.8 Strait, David: P 3.8 Hopkins, Jenni L: O 7.1, P 2.11 Straub, Susanne: O 2.6 Huang, Yu-Tuan (Doreen): O 3.3 Strawhacker, Colleen: P 3.5 Hughes, Paul: O 2.4, O 6.4 Streeter, Richard: O 3.1, P 1.1, P 1.2, P 1.5, P 3.5 I Sulpizio, Roberto: O 5.6, P 3.9 Illyinskaya, Evgenia: P 1.9 Sun, Chunqing: O 2.5, O 5.5 Ingólfsson, Ólafur: O 1.5 Suzuki, Takehiko: O 6.2, P 2.12 Insinga, Donatella: P 3.9, P 3.13 Svensson, Anders: O 1.2 Ioana, Pál: O 5.4 Szakács, Alexandru: Keynote 5, Public Lecture Ishimura, Daisuke: P 2.12 Tecsa, Viorica: P 3.16 Iverson, Nels: Keynote 3 T J Telbisz, Tamás: Keynote 5 Jaccard, Samuel: P 2.14 Thomas, Camille: P 1.4 Jegen, Marion: O 2.6 Timar-Gabor, Alida: P 2.2, P 3.3, P 3.4, P 3.16, Jenner, Frances: O 7.3 P 3.17 Jensen, Britta: P 1.6, O 1.4, O 4.6, O 6.4, P 1.13 Timm, Christian: O 7.1 Johansson, Hans: O 2.3 Timms, Rhys: P 3.1 Johnsen, Racheal: P 3.8 Toda, Shinji: P 1.11 Johnston, Richard E.: O 3.2, P 2.6 Tomlinson, Emma L.: O 5.6 Jones, Gwydion: P 1.3, P 2.3 Toohey, Matthew: Keynote 3 Jónsson, Daníel Freyr: P 1.10 Torii, Masayuki: P 1.11 Jorgensen, Murray A: P 2.7 Tóth, Mónika: O 5.1 Jovanović, Mladjen: P 3.6 Tryon, Christian A: P 2.7 Józsa, Sándor: O 5.3 U Just, Janna: O 5.6 Uslular, Göksu: O 4.1 K V Karátson, Dávid: Keynote 5, O 5.1, P 3.4, P 3.7 Vakhrameeva, Polina: O 2.2 Karlsdóttir, Sigrún: P 1.9 van Bellen, Simon: O 4.6 Kearney, Rebecca: O 5.4 Van Daele, Maarten: P 2.13 Kelemen, Szabolcs: P 2.2, P 3.17 van den Bogaard, Christel: P 1.6 Kiss, Balázs: O 5.2 Vandergoes, Marcus J: O 3.2 131

Klaminder, Jonatan: O 3.3 Vandergoes, Marcus J.: O 3.4, P 2.6 Klasen, Nicole: O 4.2 Van der Meeren, Thijs: P 2.13 Kluger, Max O: O 3.2 Veres, Daniel: Keynote 5, O 5.1, P 1.17, P 2.2, Knipping, Maria: O 2.2 P 3.2, P 3.3, P 3.4, P 3.6, P 3.7, P 3.16, P 3.17, Kobayashi, Makoto: P 2.12 Verschuren, Dirk: P 2.13 Kobayashi, Tetsuo: P 1.16 Vidal, Celine: O 6.6 Koppers, Anthony A.P.: O 4.1 Viehberg, Finn: O 6.5 Koutsodendris, Andreas: O 2.2 Villamor, Pilar: O 3.2 Krippner, Janine: P 2.9 Vincze, Ildikó: O 5.1 K. Srivastava, Ashok: O 6.3 Viola, Jannis: P 3.6 Kuehn, Stephen: P 2.9, P 2.10, P 2.7 Vlaminck, Stefan: O 2.1 Kutterolf, Steffen: O 2.6, P 2.4, P 3.14, P 3.15 Vogfjord, Kristín: P 1.9 Kyle, Philip: P 1.7 W L Waelbroeck, Claire: P 2.14 Laag, Christian: P 3.6 Wagner, Bernd: P 1.4 Lahitte, Pierre: Keynote 5 Walker, Mike: P 1.3 Lamb, Henry: O 6.5 Warmada, I Wayan: P 1.16 Lane, Christine: O 6.5, O 6.6, P 2.3, P 2.13, Wastegård, Stefan: O 1.3, O 2.3 P 3.10 Wennrich, V.: P 1.6 Langdon, Peter: P 1.15 Westgate, John: Keynote 7, P 2.15 Larsen, Guðrún: O 1.5, P 1.10, P 1.8, P 1.9 Wickham, Craig: O 7.2 Larsson, Simon: O 1.3 Wilkinson, Keith: P 3.1 Lawson, Ian: P 3.10 Williams, Frances: O 6.6 Lee, M.J.: P 1.7 Wilson, Colin: O 7.1 Lehmkuhl, Frank: O 2.1, O 4.2, P 1.17, P 3.2, Wiltshire, Rebecca: P 3.11 P 3.3, P 3.4, P 3.6, P 3.7 Wolff, Christian: P 2.13 Lehnert, Kerstin: P 2.9 Wonik, Thomas: P 1.4 Leicher, Niklas: O 5.6, P 1.4 Wu, Jiawang: P 3.9 Leng, Melanie: P 1.4, P 2.13 Wulf, Sabine: Keynote 1, Keynote 5, O 2.2, P 3.3, Leonard, Graham: O 7.1 P 3.4, P 3.7 Lethbridge, Emily: P 1.14 Wysoczanski, Richard: P 2.11 Lindsay, Jan: P 2.17 Y Lirer, Fabrizio: P 3.9 Yeoh, Jean: P 1.2 Liu, Jiaqi: O 2.5 Yirgu, Gezahegn: O 6.6 Loader, Neil: P 1.3 Zaccone, Claudio: O 4.6 Loame, Remedy C.: O 3.2, O 3.4, P 2.6 Z Longman, Jack: O 3.6 Zafu, Amdemichael: O 6.6 Lowe, David J: P 2.5, O 3.2, P 2.7, P 2.8, O 3.3, Zanchetta, Giovanni: O 5.6, P 1.4 O 3.4, P 2.6 Zawalna-Geer, Aleksandra: P 2.17 Lukács, Réka: O 5.2, O 5.3 Zeeden, Christian: O 2.1, O 4.2, P 1.17, P 3.2, M P 3.3, P 3.6, P 3.16 Machida, Hiroshi: O 6.2 Zelenin, Egor: Keynote 2, O 4.5 Magill, Christina R.: O 3.4, P 2.6 Zens, Jörg: O 2.1 Magnan, Gabriel: O 4.6 Zhang, Heng: O 3.3 Magyari, Enikő: O 5.1, P 3.4 Zhen Hui, Foo: P 1.13 Maher, Barbara: P 2.13 Zuraida, Rina: O 6.1 Manella, Giorgio: P 1.4 Manners, Hayley: O 3.6 Marean, Curtis: P 3.8 Mark, Darren: P 2.13, P 3.1 Markovic, Rastko: P 3.2

Notebook

About this book

The INQUA International Focus Group on Tephrochronology and Volcanism (INTAV) promoted the Crossing New Frontiers - Tephra Hunt in Transylvania international field conference with the aim at continuing the long tradition of successful inter-INQUA congress tephra meetings, as held previously in the USA, New Zealand, France, Canada and Japan.

The Crossing New Frontiers meeting facilitated the opportunity for presenting and discussing latest concepts and scientific accomplishments in all aspects of tephra or cryptotephra research and its applications. This book compiles the abstracts for oral and poster presentations submitted to this conference that has been guided thematically by INTAV’s current EXTRAS project: “EXTending tephRAS as a global geoscientific research tool stratigraphically, spatially, analytically, and temporally”. The main aim of EXTRAS is to help improve and develop new methodologies of tephrochronology to support and facilitate many Quaternary research initiatives ranging from paleoenvironmental reconstruction to archaeology, as well as geochronological and volcanological applications. In addition to a wide- ranging scientific programme, the conference’s field components will add exceptional insight into the history of recent Carpathian volcanism and geotectonics, as well as synchronization of regional records - including land-sea connections, landscape evolution and Quaternary palaeoenvironments in central-eastern Europe and beyond.

We acknowledge and appreciate administrative and logistical support from Romanian Academy – Cluj-Napoca Branch, and Institute of Speleology, Romanian Academy, and BayCEER, University of Bayreuth, Germany. Also, we acknowledge additional financial support kindly provided by Babes-Bolyai University, Cluj- Napoca, Romania, through the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme ERC-2015- STG (grant agreement No [678106]; PI: A. Timar-Gabor) and Department of Physical Geography, Eötvös Lorand University, Budapest, Hungary (PI: D. Karátson).

The pdf format of this Book of Abstracts can be downloaded from the conference webpage: http://www.bayceer.uni-bayreuth.de/intav2018/