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Region 19 Antarctica Pg.781
Appendix B – Region 19 Country and regional profiles of volcanic hazard and risk: Antarctica S.K. Brown1, R.S.J. Sparks1, K. Mee2, C. Vye-Brown2, E.Ilyinskaya2, S.F. Jenkins1, S.C. Loughlin2* 1University of Bristol, UK; 2British Geological Survey, UK, * Full contributor list available in Appendix B Full Download This download comprises the profiles for Region 19: Antarctica only. For the full report and all regions see Appendix B Full Download. Page numbers reflect position in the full report. The following countries are profiled here: Region 19 Antarctica Pg.781 Brown, S.K., Sparks, R.S.J., Mee, K., Vye-Brown, C., Ilyinskaya, E., Jenkins, S.F., and Loughlin, S.C. (2015) Country and regional profiles of volcanic hazard and risk. In: S.C. Loughlin, R.S.J. Sparks, S.K. Brown, S.F. Jenkins & C. Vye-Brown (eds) Global Volcanic Hazards and Risk, Cambridge: Cambridge University Press. This profile and the data therein should not be used in place of focussed assessments and information provided by local monitoring and research institutions. Region 19: Antarctica Description Figure 19.1 The distribution of Holocene volcanoes through the Antarctica region. A zone extending 200 km beyond the region’s borders shows other volcanoes whose eruptions may directly affect Antarctica. Thirty-two Holocene volcanoes are located in Antarctica. Half of these volcanoes have no confirmed eruptions recorded during the Holocene, and therefore the activity state is uncertain. A further volcano, Mount Rittmann, is not included in this count as the most recent activity here was dated in the Pleistocene, however this is geothermally active as discussed in Herbold et al. -
Surface Exposure Dating Using Cosmogenic
Surface exposure dating using cosmogenic isotopes: a field campaign in Marie Byrd Land and the Hudson Mountains Joanne S Johnson1, Karsten Gohl2, Terry L O’Donovan1, Mike J Bentley3,1 1British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 OET, UK 2Alfred Wegener Institute, Postfach 120161, D-27515, Bremerhaven, Germany 3Durham University, South Road, Durham, DH1 3LE, UK INTRODUCTION SUMMARY 2. HUNT BLUFF Here we present preliminary findings from fieldwork undertaken in Marie • We collected 7 erratic and 2 bedrock surface samples, which are Byrd Land and western Ellsworth Land (Fig.1) in March 2006, during This site is a granite outcrop along currently being processed for 10Be, 26Al and 3He dating. We will visit which we obtained samples for surface exposure dating. This work was the western side of Bear the Hudson Mountains again in 2007/8 for further sampling and supported by helicopters from RV Polarstern, on an expedition to Pine Peninsula, adjacent to the Dotson collection of geomorphological data. Island Bay. Ice Shelf. Lopatin et al. (1974) report an age of 301 Ma for the • Samples from Turtle Rock, Mt Manthe and the un-named island are Surface exposure dating provides an estimate of the time when ice granite. granite/granitoids; from Hunt Bluff we collected a meta-sandstone and retreated from a rock surface, leaving it exposed. Nucleii in rocks are basalt, in addition to granite bedrock. split apart by neutrons produced when secondary cosmic rays enter the In half a day, we found only a few • Erratic boulders at Mt Manthe and Hunt Bluff are scarce; at Turtle atmosphere. -
Geophysical Research Letters
Geophysical Research Letters RESEARCH LETTER Variation in the Distribution and Properties of Circumpolar 10.1029/2018GL077430 Deep Water in the Eastern Amundsen Sea, on Seasonal Key Points: Timescales, Using Seal-Borne Tags • In the eastern Amundsen Sea, the CDW layer is thicker in winter than in summer and contains more heat Helen K. W. Mallett1 , Lars Boehme2 , Mike Fedak2 , Karen J. Heywood1 , and salt 1 3,4 • On isopycnals, CDW is cooler and David P. Stevens , and Fabien Roquet fresher in winter, likely the result of a rising core of offshelf CDW changing 1Centre for Ocean and Atmospheric Sciences, University of East Anglia, Norwich, UK, 2Sea Mammal Research Unit, CDW properties onshelf University of St Andrews, St Andrews, UK, 3Department of Meteorology, Stockholm University, Stockholm, Sweden, • Farther south, in PIB, this seasonality 4Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden is less pronounced, likely the result of mixing as the PIB gyre recirculates CDW of different ages Abstract In the Amundsen Sea, warm saline Circumpolar Deep Water (CDW) crosses the continental shelf toward the vulnerable West Antarctic ice shelves, contributing to their basal melting. Supporting Information: Due to lack of observations, little is known about the spatial and temporal variability of CDW, • Supporting Information S1 particularly seasonally. A new data set of 6,704 seal tag temperature and salinity profiles in the easternmost trough between February and December 2014 reveals a CDW layer on average 49 dbar thicker in late Correspondence to: winter (August to October) than in late summer (February to April), the reverse seasonality of that seen K. -
Weather and Climate in the Amundsen Sea Embayment
WEATHER AND CLIMATE IN THE AMUNDSEN SEA EMBAYMENT,WEST ANTARCTICA:OBSERVATIONS, REANALYSES AND HIGH RESOLUTION MODELLING A thesis submitted to the School of Environmental Sciences of the University of East Anglia in partial fulfilment of the requirements for the degree of Doctor of Philosophy RICHARD JONES JANUARY 2018 © This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that use of any information derived there from must be in accordance with current UK Copyright Law. In addition, any quotation or extract must include full attribution. © Copyright 2018 Richard Jones iii ABSTRACT Glaciers within the Amundsen Sea Embayment (ASE) are rapidly retreating and so contributing 10% of current global sea level rise, primarily through basal melting. » Here the focus is atmospheric features that influence the mass balance of these glaciers and their representation in atmospheric models. New radiosondes and surface-based observations show that global reanalysis products contain relatively large biases in the vicinity of Pine Island Glacier (PIG), e.g. near-surface temperatures 1.8 ±C (ERA-I) to 6.8 ±C (MERRA) lower than observed. The reanalyses all underestimate wind speed during orographically-forced strong wind events and struggle to reproduce low-level jets. These biases would contribute to errors in surface heat fluxes and thus the simulated supply of ocean heat leading to PIG melting. Ten new ice cores show that there is no significant trend in accumulation on PIG between 1979 and 2013. RACMO2.3 and four global reanalysis products broadly reproduce the observed time series and the lack of any significant trend. -
Integrated Tephrochonology Copyedited
U.S. Geological Survey and The National Academies; USGS OFR-2007-xxxx, Extended Abstract.yyy, 1- Integrated tephrochronology of the West Antarctic region- Implications for a potential tephra record in the West Antarctic Ice Sheet (WAIS) Divide Ice Core N.W. Dunbar,1 W.C. McIntosh,1 A.V. Kurbatov,2 and T.I Wilch 3 1NMGB/EES Department, New Mexico Tech, Socorro NM, 87801, USA ( [email protected] , [email protected] ) 2Climate Change Institute 303 Bryand Global Sciences Center, Orono, ME, 04469, USA ([email protected]) 3Department of Geological Sciences, Albion College, Albion MI, 49224, USA ( [email protected] ) Summary Mount Berlin and Mt. Takahe, two West Antarctica volcanic centers have produced a number of explosive, ashfall generating eruptions over the past 500,000 yrs. These eruptions dispersed volcanic ash over large areas of the West Antarctic ice sheet. Evidence of these eruptions is observed at two blue ice sites (Mt. Waesche and Mt. Moulton) as well as in the Siple Dome and Byrd (Palais et al., 1988) ice cores. Geochemical correlations between tephra sampled at the source volcanoes, at blue ice sites, and in the Siple Dome ice core suggest that at least some of the eruptions covered large areas of the ice sheet with a volcanic ash, and 40 Ar/ 39 Ar dating of volcanic material provides precise timing when these events occurred. Volcanic ash from some of these events expected to be found in the WAIS Divide ice core, providing chronology and inter-site correlation. Citation: Dunbar, N.W., McIntosh, W.C., Kurbatov, A., and T.I Wilch (2007), Integrated tephrochronology of the West Antarctic region- Implications for a potential tephra record in the West Antarctic Ice Sheet (WAIS) Divide Ice Core, in Antarctica: A Keystone in a Changing World – Online Proceedings of the 10 th ISAES X, edited by A. -
Tephrochronology: Methodology and Correlations, Antarctic Peninsula Area
Tephrochronology: Methodology and correlations, Antarctic Peninsula Area Mats Molén Thesis in Physical Geography 30 ECTS Master’s Level Report passed: November 9 2012 Supervisor: Rolf Zale Tephrochronology: Methodology and correlations, Antarctic Peninsula Area Abstract Methods for tephrochronology are evaluated, in the following way: Lake sediments <500 years old from three small Antarctic lakes were analysed for identification of tephras. Subsamples were analysed for a) grain size, and identification and concentration of volcanogenic grains, b) identification of tephra horizons, c) element abundance by EPMA WDS/EDS and LA-ICP-MS, and d) possible correlations between lakes and volcanoes. Volcanogenic minerals and shards were found all through the sediment cores in all three lakes, in different abundances. A high background population of volcanogenic mineral grains, in all samples, made the identification of tephra horizons difficult, and shards could only be distinguished by certainty after chemical analysis of elements. The tephra layers commonly could not be seen by the naked eye, and, hence they are regarded as cryptotephras. Because of the small size of recent eruptions in the research area, and the travel distance of ash, most shards are small and difficult to analyse. Nine possible tephra horizons have been recorded in the three lakes, and preliminary correlations have been made. But because of analytical problems, the proposed correlations between the lakes and possible volcanic sources are preliminary. Table of contents 1. Introduction . 1 1.1. Advances and problems of tephrochronology . 1 1.1.1. General observations .. 1 1.1.2. Difficulties in tephrochronology work .. 2 1.1.3. The current research .. 4 1.2. -
What If Antarctica's Volcanoes Erupt
What if Antarctica's dormant, ice-covered volcanoes wake up? John Smellie, Department of Geology, University of Leicester (This article was originally published in The Conversation, on 4 September 2017 [https://theconversation.com/what-if-antarcticas-dormant-ice-covered-volcanoes-wake-up-83450]) Antarctica is a vast icy wasteland covered by the world’s largest ice sheet. This ice sheet contains about 90% of fresh water on the planet. It acts as a massive heat sink and its meltwater drives the world’s oceanic circulation. Its existence is therefore a fundamental part of Earth’s climate. Less well known is that Antarctica is also host to several active volcanoes, part of a huge "volcanic province" which extends for thousands of kilometres along the Western edge of the continent. Although the volcanic province has been known and studied for decades, recently about 100 "new" volcanoes were recently discovered beneath the ice by scientists who used satellite data and ice- penetrating radar to search for hidden peaks. These sub-ice volcanoes may be dormant. But what would happen if Antarctica’s volcanoes awoke? IMAGE: Some of the volcanoes known about before the latest discovery. Source: antarcticglaciers.org (image: JL Smellie) We can get some idea by looking to the past. One of Antarctica’s volcanoes, Mount Takahe, is found close to the remote centre of the West Antarctic Ice Sheet. In a new study, scientists implicate Takahe in a series of eruptions rich in ozone-consuming halogens that occurred about 18,000 years ago. These eruptions, they claim, triggered an ancient ozone hole, warmed the southern hemisphere causing glaciers to melt, and helped bring the last ice age to a close. -
Thurston Island
RESEARCH ARTICLE Thurston Island (West Antarctica) Between Gondwana 10.1029/2018TC005150 Subduction and Continental Separation: A Multistage Key Points: • First apatite fission track and apatite Evolution Revealed by Apatite Thermochronology ‐ ‐ (U Th Sm)/He data of Thurston Maximilian Zundel1 , Cornelia Spiegel1, André Mehling1, Frank Lisker1 , Island constrain thermal evolution 2 3 3 since the Late Paleozoic Claus‐Dieter Hillenbrand , Patrick Monien , and Andreas Klügel • Basin development occurred on 1 2 Thurston Island during the Jurassic Department of Geosciences, Geodynamics of Polar Regions, University of Bremen, Bremen, Germany, British Antarctic and Early Cretaceous Survey, Cambridge, UK, 3Department of Geosciences, Petrology of the Ocean Crust, University of Bremen, Bremen, • ‐ Early to mid Cretaceous Germany convergence on Thurston Island was replaced at ~95 Ma by extension and continental breakup Abstract The first low‐temperature thermochronological data from Thurston Island, West Antarctica, ‐ fi Supporting Information: provide insights into the poorly constrained thermotectonic evolution of the paleo Paci c margin of • Supporting Information S1 Gondwana since the Late Paleozoic. Here we present the first apatite fission track and apatite (U‐Th‐Sm)/He data from Carboniferous to mid‐Cretaceous (meta‐) igneous rocks from the Thurston Island area. Thermal history modeling of apatite fission track dates of 145–92 Ma and apatite (U‐Th‐Sm)/He dates of 112–71 Correspondence to: Ma, in combination with kinematic indicators, geological -
Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs Amanda Colleen Lough Washington University in St
Washington University in St. Louis Washington University Open Scholarship All Theses and Dissertations (ETDs) Summer 9-1-2014 Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs Amanda Colleen Lough Washington University in St. Louis Follow this and additional works at: https://openscholarship.wustl.edu/etd Recommended Citation Lough, Amanda Colleen, "Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs" (2014). All Theses and Dissertations (ETDs). 1319. https://openscholarship.wustl.edu/etd/1319 This Dissertation is brought to you for free and open access by Washington University Open Scholarship. It has been accepted for inclusion in All Theses and Dissertations (ETDs) by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY IN ST. LOUIS Department of Earth and Planetary Sciences Dissertation Examination Committee: Douglas Wiens, Chair Jill Pasteris Philip Skemer Viatcheslav Solomatov Linda Warren Michael Wysession Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs by Amanda Colleen Lough A dissertation presented to the Graduate School of Arts and Sciences of Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 2014 St. Louis, Missouri © 2014, Amanda Colleen Lough Table of Contents List of Figures ............................................................................................................................. -
Late Quaternary Volcanic Activity in Marie Byrd Land: Potential 40Ar/39Ar-Dated Time Horizons in West Antarctic Ice and Marine Cores
Late Quaternary volcanic activity in Marie Byrd Land: Potential 40Ar/39Ar-dated time horizons in West Antarctic ice and marine cores T. I. Wilch* Department of Geological Sciences, Albion College, Albion, Michigan 49224 W. C. McIntosh Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, and New Mexico Bureau of Mines and Mineral Resources, Socorro, New Mexico 87801 N. W. Dunbar New Mexico Bureau of Mines and Mineral Resources, Socorro, New Mexico 87801 ABSTRACT More than 12 40Ar/39Ar-dated tephra lay- ies is to determine the basal age of the ice sheet. ers, exposed in bare ice on the summit ice cap The 1968 Byrd Station ice core in the West Late Quaternary volcanic activity at three of Mount Moulton, 30 km from their inferred Antarctic Ice Sheet has an inferred basal age of major alkaline composite volcanoes in Marie source at Mount Berlin, range in age from 492 only 74 ka (Hammer et al., 1994). The exten- Byrd Land, West Antarctica, is dominated by to 15 ka. These englacial tephra layers provide sive lateral flow of ice from the ice divide area explosive eruptions, many capable of deposit- a minimum age of 492 ka for the oldest iso- to Byrd Station may have removed or disturbed ing ash layers as regional time-stratigraphic topically dated ice in West Antarctica. This much of the basal ice record. Consequently, the horizons in the West Antarctic Ice Sheet and well-dated section of locally derived glacial ice 74 ka date of the Byrd core provides only a in Southern Ocean marine sediments. -
Late Quaternary Environmental Changes in Marguerite Bay, Antarctic Peninsula, Inferred from Lake Sediments and Raised Beaches
Quaternary Science Reviews 68 (2013) 216e236 Contents lists available at SciVerse ScienceDirect Quaternary Science Reviews journal homepage: www.elsevier.com/locate/quascirev Late Quaternary environmental changes in Marguerite Bay, Antarctic Peninsula, inferred from lake sediments and raised beaches Dominic A. Hodgson a,*,1, Stephen J. Roberts a,1, James A. Smith a, Elie Verleyen b, Mieke Sterken b, Minke Labarque b, Koen Sabbe b, Wim Vyverman b, Claire S. Allen a, Melanie J. Leng c, Charlotte Bryant d a NERC British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK b Department of Biology, Section of Protistology and Aquatic Ecology, University of Ghent, Krijgslaan 281 S8, 9000 Gent, Belgium c NERC Isotope Geosciences Laboratory, British Geological Survey, Keyworth, Nottingham NG12 5GG, UK d NERC Radiocarbon Facility, Scottish Enterprise Technology Park, Rankine Avenue, East Kilbride, Scotland G75 OQF, UK article info abstract Article history: The Antarctic Peninsula is one of the fastest-warming regions on Earth, but its palaeoenvironmental Received 4 October 2012 history south of 63 latitude is relatively poorly documented, relying principally on the marine geological Received in revised form record and short ice cores. In this paper, we present evidence of late-Quaternary environmental change 30 January 2013 from the Marguerite Bay region combining data from lake sediment records on Horseshoe Island and Accepted 1 February 2013 Pourquoi-Pas Island, and raised beaches at Horseshoe Island, Pourquoi-Pas Island and Calmette Bay. Lake Available online 27 March 2013 sediments were radiocarbon dated and analysed using a combination of sedimentological, geochemical and microfossil methods. Raised beaches were surveyed and analysed for changes in clast composition, Keywords: Antarctic Peninsula size and roundness. -
The CMS Tumbler
The CMS June Tumbler 2021 The monthly newsletter of the Cascade Mineralogical Society, Inc., Kent, Washington Connect with us! Next Meeting: Website: https://www.cascademineralogicalsociety.org Club Facebook: https://www.facebook.com/CasMinSoc/ June 10, 2021 Show Facebook: https://www.facebook.com/cascadegemandmineralshow 7:00 p.m. Instagram: https://www.instagram.com/cascadegemandmineralshow/ This month remember American Legion Hall to wish a 25406 97th Pl S Happy Birthday to Michelle Patterson on June 2 Kent, WA Leonard Bahr on June 7 Charles Benedict on June 10 The Program is about Isaac Fu on June 11 Charleen Shoemaker on June 11 Picture Stones Michael Watson on June 11 Shelley Opel on June 16 The Show & Tell Becky Patterson on June 21 Theme is something Margaret Squires on June 27 Brenda Haworth on June 29 you've done or acquired in Dick Morgan on June 29 the last 15 months and also remember to wish a Happy Anniversary to Table of Contents Calendar...........................................................3 Robert & Mrs. Waddell on June 8 (7 years) Cartoons...................................................3 & 11 From the Top of the Rock Pile.........................5 Land Use Bills..................................................5 Ice Towers........................................................7 Young Richard's Almanac................................7 Colors Around the World..................................8 May Field Trip Report.......................................9 Field Trips........................................................11 Shows..............................................................12 Except where otherwise noted, material from The Tumbler may be reprinted for non-commercial purposes, provided that the author(s) and source are acknowledged. For commercial use, the author(s) must be contacted for permission; if no contact information is given, contact them via the editor. Tips, suggestions, recipes and experiments printed in this newsletter are the experiences and/or opinions of the individuals submitting them.