DOCSLIB.ORG

Ice Dynamics and Ocean Productivity During the Late Miocene, Offshore Wilkes Land, East Antarctica

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ice Dynamics and Ocean Productivity During the Late Miocene, Offshore Wilkes Land, East Antarctica ICE DYNAMICS AND OCEAN PRODUCTIVITY DURING THE LATE MIOCENE, OFFSHORE WILKES LAND, EAST ANTARCTICA by Rebecca Frances Pretty A thesis submitted to Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Geology Antarctic Research Centre Victoria University of Wellington 2019 ii ABSTRACT The middle Miocene Climatic Transition (~14 Ma) is commonly interpreted to represent the significant advance of the East Antarctic Ice Sheet (EAIS), and the transition to a hyper-arid climate and a stable polar-styled ice sheet. However, an increasing number of studies provide evidence for continued instability and abundant meltwater processes influencing the low-lying margins of the EAIS during the Late Miocene (~11.6-5.3 Ma). The history of the EAIS during this period remains ambiguous due to the sparse number of records, and those that do exist have poor age resolution. This thesis investigates Integrated Ocean Drilling Program Site U1361 (64°24.5°S 143°53.1°E), located on the lowermost continental rise of the Wilkes Land margin. It aims to assess the variability of the EAIS and associated changes in palaeoceanography offshore one of the largest marine-based sectors of East Antarctica, the Wilkes Subglacial Basin, and to establish if the EAIS was responding to orbital forcings during the Late Miocene. The study period (~11.7 to 10.8 Ma) contains six intervals of nannofossil-rich mudstones, interbedded with laminated mudstones and diatom-rich mudstones. Nannofossils are absent elsewhere in core U1361A, which covers the past ~14 Ma. To identify the sedimentary and depositional processes which influenced this anomalous interval of calcareous biological productivity, a high-resolution record (using ~450 samples) of Iceberg Rafted Debris (IBRD), grain size analysis and bulk geochemistry XRF analysis have been developed. A lithofacies scheme has been established and used to provide an interpretation of the shifting sedimentary processes through time. Repeating cycles of faintly laminated mudstones were interpreted to represent the influence of bottom current activity on overbank turbidites, that spill onto a channel leeve, during glacial periods. The contouritic nature of the facies is likely associated with the low-relief channel-levee system at this time. Interglacial sedimentation is characterised by an increase in biogenic content, IBRD and bioturbation, with deposition occurring during biologically productive open marine conditions. Two types of biogenic productivity are present over the interval (silica and/or carbonate). The intervals of diatom-rich mud were interpreted to be associated with enhanced upwelling of Circumpolar Deep Water (CDW). While, the nannofossil-rich mudstones suggest a significantly warmer climate, with coccolithophore production iii proposed to represent the influence of meltwater and shifting Southern Ocean frontal systems, acting to restrict nutrient upwelling and increase water temperatures. Nannofossil-rich muds are only present for a short interval (700 kyr), suggesting that the anomalous depositional environment between ~11.7 to 11.0 Ma was potentially related to the significant retreat and surface meltwater processes at the EAIS margin. Interglacial sedimentation at Site U1361 is also accompanied by an increase in grain size (i.e. silt), interpreted to represent oceanic current intensification which acts to restrict the deposition of finer material, relative to glacial intervals. This intensification of ocean current strength may have resulted in increased heat delivery to the EAIS margin triggering a terrestrial based ice sheet, and the delivery of nutrients stimulating marine productivity. Spectral analysis of the mean grain size (MGS) and IBRD Mass Accumulation Rate (MAR) records revealed that during the Late Miocene (~11.7 to 10.8 Ma), the ice sheet was paced by ~100 kyr eccentricity cycles, and a low frequency ~20 kyr processional component. This is consistent with two Late Miocene �18O records that are also paced by eccentricity, suggesting that the Antarctic Ice Sheet was contributing a significant signal to the global �18O record during this interval of the Late Miocene. However, the presence of nannofossil suggests a warmer world, rather than the colder climate state that are often inferred to lead to eccentricity/precession variability. A recent hypothesis proposed by Levy et al., (2019) invokes that a warmer climate may lead to surface melt processes which at high latitudes are dominated by eccentricity/precession. Although this style of climate is commonly thought to have occurred prior to ~14 Ma in East Antarctica, the evidence presented in this study suggests such a state existed at the Wilkes Land margin until at least ~11.0 Ma. iv ACKNOWLEDGMENTS This thesis would not have been possible without the support and guidance of so many people. First and foremost, a massive thank you to my supervisors, Rob McKay and Gavin Dunbar. Rob, thank you for your constant support and guidance through this project. Your encouragement and enthusiasm helped to bring down my stress level and made this project very enjoyable to be part of. Gavin, thank you for your helpful insight into lab work, particularly with XRF lab work, and useful discussions on data interpretations. I would also like to thank many others who contributed to this research. A big thank you to Jane Chewings for your endless help and encouragement in the laboratory. Without your guidance I don’t think my lab work would have been possible. A massive thank you to Bella Duncan for spending hours teaching me the methods of biomarker analysis and data processing. Lastly, thank you to the SGEES and ARC staff and students who made my time as an undergraduate and postgraduate student at VUW a very enjoyable experience. To my family, I could not have done this without you. Mum and Dad, thank you for your love and support over the years, allowing me to strive for excellence and to never give up. To Benjamin and William, the best brothers an older sister could have! Thank you for checking up on me, it has been great having you both in Wellington over the last couple of years. To my friends, each one of you has been amazing, providing endless encouragement, love, laughter and some much-needed proofreading. A special thank you to Damian, for your support and love throughout this project. I would like to acknowledge the Rutherford Discovery Fellowship to Rob McKay for funding this project. Lastly, the shipboard scientists of the International Ocean Drilling Program Leg 318 for successful recovery and previous analysis on such an amazing sedimentary core. v TABLE OF CONTENTS 1 Chapter one: Introduction ......................................................................................... 1 1.1 Context ............................................................................................................... 1 1.2 Study Location ................................................................................................... 4 1.3 Thesis aims and objectives ................................................................................. 6 2 Chapter two: Background ......................................................................................... 7 2.1 Antarctic ice sheet history – proximal and far-field records .............................. 7 Cenozoic climate and initiation of the Antarctic Ice Sheets ....................... 8 Mid-Miocene Climatic Optimum.............................................................. 11 Mid-Miocene Transition ........................................................................... 12 Late Miocene – was the EAIS dynamic or stable? ................................... 12 Pliocene climate and ice sheet style .......................................................... 14 2.2 Global productivity during the Late Miocene .................................................. 15 2.3 Internal drivers of climate change .................................................................... 18 Orbital cycles ............................................................................................ 18 Milankovitch theory of the Ice Ages ......................................................... 19 Milankovitch cycles- the pre-100 kyr world ............................................. 20 Orbital patterns deep sea records during the Late Miocene ...................... 21 Southern oceans role in atmospheric CO2 concentrations ........................ 22 2.4 Sedimentation on glaciated margins................................................................. 24 Turbidity currents ...................................................................................... 25 Bottom currents ......................................................................................... 27 Pelagic and hemipelagic settling ............................................................... 28 Iceberg Rafted Debris ............................................................................... 28 Glacial/interglacial sedimentation ............................................................. 30 2.5 Nannofossil production .................................................................................... 31 vi Significance of nannofossils in Antarctica ................................................ 32 2.6 Biomarkers (focusing on n-Alkanes)................................................................ 32 2.7 Productivity proxies ........................................................................................
Load more

Recommended publications
  • Air and Shipborne Magnetic Surveys of the Antarctic Into the 21St Century
    TECTO-125389; No of Pages 10 Tectonophysics xxx (2012) xxx–xxx Contents lists available at SciVerse ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Air and shipborne magnetic surveys of the Antarctic into the 21st century A. Golynsky a,⁎,R.Bellb,1, D. Blankenship c,2,D.Damasked,3,F.Ferracciolie,4,C.Finnf,5,D.Golynskya,6, S. Ivanov g,7,W.Jokath,8,V.Masolovg,6,S.Riedelh,7,R.vonFresei,9,D.Youngc,2 and ADMAP Working Group a VNIIOkeangeologia, 1, Angliysky Avenue, St.-Petersburg, 190121, Russia b LDEO of Columbia University, 61, Route 9W, PO Box 1000, Palisades, NY 10964-8000, USA c University of Texas, Institute for Geophysics, 4412 Spicewood Springs Rd., Bldg. 600, Austin, Texas 78759-4445, USA d BGR, Stilleweg 2 D-30655, Hannover, Germany e BAS, High Cross, Madingley Road, Cambridge, CB3 OET, UK f USGS, Denver Federal Center, Box 25046 Denver, CO 80255, USA g PMGE, 24, Pobeda St., Lomonosov, 189510, Russia h AWI, Columbusstrasse, 27568, Bremerhaven, Germany i School of Earth Sciences, The Ohio State University, 125 S. Oval Mall, Columbus, OH, 43210, USA article info abstract Article history: The Antarctic geomagnetics' community remains very active in crustal anomaly mapping. More than 1.5 million Received 1 August 2011 line-km of new air- and shipborne data have been acquired over the past decade by the international community Received in revised form 27 January 2012 in Antarctica. These new data together with surveys that previously were not in the public domain significantly Accepted 13 February 2012 upgrade the ADMAP compilation.
    [Show full text]
  • Antarctic Peninsula
    Hucke-Gaete, R, Torres, D. & Vallejos, V. 1997c. Entanglement of Antarctic fur seals, Arctocephalus gazella, by marine debris at Cape Shirreff and San Telmo Islets, Livingston Island, Antarctica: 1998-1997. Serie Científica Instituto Antártico Chileno 47: 123-135. Hucke-Gaete, R., Osman, L.P., Moreno, C.A. & Torres, D. 2004. Examining natural population growth from near extinction: the case of the Antarctic fur seal at the South Shetlands, Antarctica. Polar Biology 27 (5): 304–311 Huckstadt, L., Costa, D. P., McDonald, B. I., Tremblay, Y., Crocker, D. E., Goebel, M. E. & Fedak, M. E. 2006. Habitat Selection and Foraging Behavior of Southern Elephant Seals in the Western Antarctic Peninsula. American Geophysical Union, Fall Meeting 2006, abstract #OS33A-1684. INACH (Instituto Antártico Chileno) 2010. Chilean Antarctic Program of Scientific Research 2009-2010. Chilean Antarctic Institute Research Projects Department. Santiago, Chile. Kawaguchi, S., Nicol, S., Taki, K. & Naganobu, M. 2006. Fishing ground selection in the Antarctic krill fishery: Trends in patterns across years, seasons and nations. CCAMLR Science, 13: 117–141. Krause, D. J., Goebel, M. E., Marshall, G. J., & Abernathy, K. (2015). Novel foraging strategies observed in a growing leopard seal (Hydrurga leptonyx) population at Livingston Island, Antarctic Peninsula. Animal Biotelemetry, 3:24. Krause, D.J., Goebel, M.E., Marshall. G.J. & Abernathy, K. In Press. Summer diving and haul-out behavior of leopard seals (Hydrurga leptonyx) near mesopredator breeding colonies at Livingston Island, Antarctic Peninsula. Marine Mammal Science.Leppe, M., Fernandoy, F., Palma-Heldt, S. & Moisan, P 2004. Flora mesozoica en los depósitos morrénicos de cabo Shirreff, isla Livingston, Shetland del Sur, Península Antártica, in Actas del 10º Congreso Geológico Chileno.
    [Show full text]
  • The Antarctic Treaty
    The Antarctic Treaty Measures adopted at the Thirty-ninth Consultative Meeting held at Santiago, Chile 23 May – 1 June 2016 Presented to Parliament by the Secretary of State for Foreign and Commonwealth Affairs by Command of Her Majesty November 2017 Cm 9542 © Crown copyright 2017 This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned. This publication is available at www.gov.uk/government/publications Any enquiries regarding this publication should be sent to us at Treaty Section, Foreign and Commonwealth Office, King Charles Street, London, SW1A 2AH ISBN 978-1-5286-0126-9 CCS1117441642 11/17 Printed on paper containing 75% recycled fibre content minimum Printed in the UK by the APS Group on behalf of the Controller of Her Majestyʼs Stationery Office MEASURES ADOPTED AT THE THIRTY-NINTH ANTARCTIC TREATY CONSULTATIVE MEETING Santiago, Chile 23 May – 1 June 2016 The Measures1 adopted at the Thirty-ninth Antarctic Treaty Consultative Meeting are reproduced below from the Final Report of the Meeting. In accordance with Article IX, paragraph 4, of the Antarctic Treaty, the Measures adopted at Consultative Meetings become effective upon approval by all Contracting Parties whose representatives were entitled to participate in the meeting at which they were adopted (i.e. all the Consultative Parties). The full text of the Final Report of the Meeting, including the Decisions and Resolutions adopted at that Meeting and colour copies of the maps found in this command paper, is available on the website of the Antarctic Treaty Secretariat at www.ats.aq/documents.
    [Show full text]
  • Federal Register/Vol. 84, No. 78/Tuesday, April 23, 2019/Rules
    Federal Register / Vol. 84, No. 78 / Tuesday, April 23, 2019 / Rules and Regulations 16791 U.S.C. 3501 et seq., nor does it require Agricultural commodities, Pesticides SUPPLEMENTARY INFORMATION: The any special considerations under and pests, Reporting and recordkeeping Antarctic Conservation Act of 1978, as Executive Order 12898, entitled requirements. amended (‘‘ACA’’) (16 U.S.C. 2401, et ‘‘Federal Actions to Address Dated: April 12, 2019. seq.) implements the Protocol on Environmental Justice in Minority Environmental Protection to the Richard P. Keigwin, Jr., Populations and Low-Income Antarctic Treaty (‘‘the Protocol’’). Populations’’ (59 FR 7629, February 16, Director, Office of Pesticide Programs. Annex V contains provisions for the 1994). Therefore, 40 CFR chapter I is protection of specially designated areas Since tolerances and exemptions that amended as follows: specially managed areas and historic are established on the basis of a petition sites and monuments. Section 2405 of under FFDCA section 408(d), such as PART 180—[AMENDED] title 16 of the ACA directs the Director the tolerance exemption in this action, of the National Science Foundation to ■ do not require the issuance of a 1. The authority citation for part 180 issue such regulations as are necessary proposed rule, the requirements of the continues to read as follows: and appropriate to implement Annex V Regulatory Flexibility Act (5 U.S.C. 601 Authority: 21 U.S.C. 321(q), 346a and 371. to the Protocol. et seq.) do not apply. ■ 2. Add § 180.1365 to subpart D to read The Antarctic Treaty Parties, which This action directly regulates growers, as follows: includes the United States, periodically food processors, food handlers, and food adopt measures to establish, consolidate retailers, not States or tribes.
    [Show full text]
  • Argentine and Chilean Claims to British Antarctica. - Bases Established in the South Shetlands
    Keesing's Record of World Events (formerly Keesing's Contemporary Archives), Volume VI-VII, February, 1948 Argentine, Chilean, British, Page 9133 © 1931-2006 Keesing's Worldwide, LLC - All Rights Reserved. Argentine and Chilean Claims to British Antarctica. - Bases established in the South Shetlands. - Chilean President inaugurates Chilean Army Bases on Greenwich Island. - Argentine Naval Demonstration in British Antarctic Waters. - H.M.S. "Nigeria" despatched to Falklands. - British Government Statements. - Argentine-Chilean Agreement on Joint Defence of "Antarctic Rights." - The Byrd and Ronne Antarctic Expeditions. - Australian Antarctic Expedition occupies Heard Islands. The Foreign-Office in London, in statements on Feb. 7 and Feb. 13, announced that Argentina and Chile had rejected British protests, earlier presented in Buenos Aires and Santiago, against the action of those countries in establishing bases in British Antarctic territories. The announcement of Feb. 7 stated that on Dec. 7, 1947, the British Ambassador in Buenos Aires, Sir Reginald Leeper, had presented a Note expressing British "anxiety" at the activities in the Antarctic of an Argentine naval expedition which had visited part of the Falkland Islands Dependencies, including Graham Land, the South Shetlands, and the South Orkneys, and had landed at various points in British territory; that a request had been made for Argentine nationals to evacuate bases established on Deception Island and Gamma Island, in the South Shetlands; that H.M. Government had proposed that the Argentine should submit her claim to Antarctic sovereignty to the International Court of Justice for adjudication; and that on Dec. 23, 1947, a second British Note had been presented expressing surprise at continued violations of British territory and territorial waters by Argentine vessels in the Antarctic.
    [Show full text]
  • EGU2016-2717, 2016 EGU General Assembly 2016 © Author(S) 2016
    Geophysical Research Abstracts Vol. 18, EGU2016-2717, 2016 EGU General Assembly 2016 © Author(s) 2016. CC Attribution 3.0 License. Oligocene to Miocene terrestrial climate change and the demise of forests on Wilkes Land, East Antarctica Ulrich Salzmann (1), Stephanie Strother (1), Francesca Sangiorgi (2), Peter Bijl (2), Joerg Pross (3), John Woodward (1), Carlota Escutia (4), Henk Brinkhuis (5,2) (1) Northumbria University, Faculty of Engineering and Environment, Geography, Newcastle upon Tyne, United Kingdom ([email protected]), (2) Biomarine Sciences, Institute of Environmental Biology, Faculty of Science, Laboratory of Palaeobotany and Palynology, Utrecht University, Utrecht, The Netherlands , (3) Paleoenvironmental Dynamics Group, Institute of Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234, 69120 Heidelberg, Germany , (4) Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada, Granada, Spain , (5) NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Organic Biogeochemistry, Den Burg, Texel, The Netherlands The question whether Cenozoic climate was warm enough to support a substantial vegetation cover on the Antarc- tic continent is of great significance to the ongoing controversial debate on the dynamic behaviour of Antarctic land ice during the transition from a greenhouse to an icehouse world. Here we present palynological results from an Oligocene to Miocene sediment record provided by the Integrated Ocean Drilling Program Expedition 318 to the Wilkes Land margin (East Antarctica). The Oligocene assemblages (33.9-23 Ma) are dominated by pollen and spores from temperate forest and sub-Antarctic shrub vegetation inhabiting different altitudinal zones. These in- clude a lowland cold temperate forest with Dacrydium and Lagarostrobos (both common in southern forests of New Zealand and Tasmania today) and a high altitude tundra shrubland comprising Microcachrys, Nothofagus (southern beech) and Podocarpaceae conifers.
    [Show full text]
  • USGS Open-File Report 2007-1047 Extended Abstract
    U.S. Geological Survey and The National Academies; USGS OF-2007-1047, Extended Abstract 126 Late Quaternary sediment record of six glacial/interglacial cycles off the Wilkes Land - Adelie Land Coast (East Antarctica): Preliminary geochemical results 1 2 2 2 3 3 3 3 M. Presti, L. Barbara, D. Denis, X. Crosta, E. De Voos, M. Lipizer, C. De Vittor, A. Acquavita, 4 1 C. Kissel, and L. De Santis 1Dip di Geofisica della Litosfera, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/c, 34010 Sgonico (Trieste), Italy ([email protected]), 2EPOC, Université Bordeaux I UMR-CNRS 5805, Avenue des Facultés, 33405 Talence Cedex, France, 3Dip. di Oceanografia Geologica, Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS), via Piccard, 54, 34014 S. Croce (Trieste), Italy, 4LSCE, CNRS Gif-sur-Yvette, Avenue de la Terrasse, Bat 12, Gif-sur-Yvette, 91198, France. Summary The IMAGES-CADO (Coring Adélie Diatom Oozes) research cruise targeted in 2003 the Adelie Land Coast, which lays seaward of one of the largest, marine-based sectors of the East Antarctic Ice Sheet (Wilkes Basin). It is also a site of production of the Adelie Land Bottom Water, which ventilates the deep ocean and contributes to the global thermohaline circulation. MD03-2603, a ~32 m long piston core, was collected on a sediment mound on the continental rise, with the aim of investigating the late-Quaternary depositional environment in relation to the past ice- sheet and oceanographic conditions. Geochemical/compositional information has been compared to isotopic, biostratigraphic and paleomagnetic data, leading to the identification of six glacial/interglacial climatic cycles in the sediment.
    [Show full text]
  • Radarsat: the Antarctic Mapping Project
    Radarsat: The Antarctic Mapping Project Science Requirements and Related Documentation September, 1996 compiled from materials prepared by: K. Jezek, J. Crawford, B. Holt, F. Carsey, G. Reynolds, R. Harding, M. Forbes, K. Lord, J. Muller, L. Norikane, J. Curlander, R. Onstott Concurrence __________________________ K. Jezek Byrd Polar Research Center ___________________________ C. Wales Alaska SAR Facility ____________________________ F. Carsey Jet Propulsion Laboratory ___________________________ P. Liggett Jet Propulsion Laboratory _____________________________ Dave Nichols Jet Propulsion Laboratory _______________________________ Martha Maiden NASA ________________________________ Robert Thomas NASA 2 Revisions October 10, 1996 Section III 3) Scan Results File generated within 12 hours of acquisition and/or receipt at ASF; the oldest data on hand will receive the highest priority. There must be capability to generate scan results files from data using standard beams 1-7 and extended beams 1-4 (ASF) 8) ASF must process full-res, quick-look images of all Radarsat standard beam (SB1-3) data acquired over the Antarctic coast within 12 hours of acquistion/receipt. ASF should have the capability to transfer any of these image data for subsequent manipulation by the RAMP team. (ASF) 9) Provide for local storage of all coastal, standard-beam images at full-resolution: provide capability for electronic side-lap (sliver) checking; provide capability to create hardcopy (paper) products of all coastal data. (JPL) 3 Project Summary On November 4, 1995, the Canadian RADARSAT was carried aloft by a NASA rocket launched from Vandenburg Air Force Base. Radarsat is equipped with a C-band Synthetic Aperture Radar (SAR) capable of acquiring high resolution (25 m) images of Earth’s surface day or night and under all weather conditions.
    [Show full text]
  • JOIDES Resolution Expedition 318 (Wilkes Land Glacial History) Site
    IODP Expedition 318: Wilkes Land Glacial History Site U1357 Summary 26 February 2010 The primary objective at Site U1357 (ADEL-01B) was to recover a continuous ~200 meter Holocene sedimentary section from the Adélie Basin located on the Antarctic continental shelf off the Wilkes Land Margin. The Adélie Basin is a 1000 meter deep glacially-scoured trough separated from the Adélie Depression (70 km to the east) by the 200 m deep Adélie Bank. Previous piston- and kasten-coring of the upper sediment column shows that sediments in the Adélie Basin are deposited as annual-to-near-annual layers averaging 2 cm in thickness. The thickness of the Holocene sedimentary section above the last glacial diamict (190 m) is consistent with this high rate of sedimentation being maintained for the past 10,000 years. The ultra-high resolution Adélie Basin Holocene section will be used to produce the first annually-resolved time series of oceanographic and climatic variability derived from a Southern Ocean marine sediment core. These data can be directly compared to annual ice core records from Antarctica’s coastal ice domes as well as other marine sediment cores from the Antarctic Peninsula and other parts of the East Antarctic Margin. The site is sensitive to drainage winds from Antarctica as well as the polar easterly winds, sea ice extent, the Southern Annular Mode (SAM), and the position of the southern boundary of the Antarctic Polar Frontal Zone in the Indian and Pacific oceans. Little is known about past variability in these systems from marine records and there are none with annual or near-annual resolution.
    [Show full text]
  • Identification of Reworking in Eocene to Miocene Pollen Records from Offshore Antarctica: a New Approach Using Red Fluorescence
    Biogeosciences Discuss., doi:10.5194/bg-2016-391, 2016 Manuscript under review for journal Biogeosciences Published: 24 October 2016 c Author(s) 2016. CC-BY 3.0 License. Identification of reworking in Eocene to Miocene pollen records from offshore Antarctica: a new approach using red fluorescence Stephanie L. Strother1, Ulrich Salzmann1, Francesca Sangiorgi2, Peter K. Bijl2, Jörg Pross3, John 5 Woodward1, Matthew J. Pound1 1Department of Geography, Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne, NE1 8ST, UK 2Marine Palynology and Paleoceanography, Department of Earth Sciences, Faculty of Geosciences, Laboratory of Palaeobotany and Palynology, Utrecht University, Heidelberglaan 2, 3584CS Utrecht, The Netherlands 10 3Paleoenvironmental Dynamics Group, Institute of Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234, D-69120 Heidelberg, Germany Correspondence to: Stephanie Strother ([email protected]) and Ulrich Salzmann ([email protected]) Abstract. Antarctic palaeoclimate evolution and vegetation history after the formation of a continent-scale 15 cryosphere at the Eocene/Oligocene boundary, 33.9 million years ago, has remained a matter of controversy. In particular, the reconstruction of terrestrial climate and vegetation has been strongly hampered by uncertainties in unambiguously identifying in situ as opposed to reworked sporomorphs that have been transported into Antarctic marine sedimentary records by waxing and waning ice sheets. Whereas reworked sporomorph grains over longer non-successive geological time scales are easily identifiable within younger sporomorph assemblages (e.g., Permian 20 sporomorphs in Pliocene sediments), distinguishing in situ from reworked material in palynological assemblages over successive geological time periods (e.g., Eocene sporomorphs in Oligocene sediments) has remained problematic.
    [Show full text]
  • Final Report of the Twenty-Ninth Antarctic Treaty Consultative Meeting
    Final Report of the Twenty-ninth Antarctic Treaty Consultative Meeting ANTARCTIC TREATY CONSULTATIVE MEETING Final Report of the Twenty-ninth Antarctic Treaty Consultative Meeting Edinburgh, United Kingdom 12 – 23 June 2006 Secretariat of the Antarctic Treaty Buenos Aires 2006 Antarctic Treaty Consultative Meeting (29th : 2006 : Edinburgh) Final Report of the Twenty-ninth Antarctic Treaty Consultative Meeting. Edinburgh, United Kingdom, 12-23 June 2006. Buenos Aires : Secretariat of the Antarctic Treaty, 2006. 564 p. ISBN 987-23163-0-9 1. International law – Environmental issues. 2. Antarctic Treaty System. 3. Environmental law – Antarctica. 4. Environmental protection – Antarctica. DDC 341.762 5 ISBN-10: 987-23163-0-9 ISBN-13: 978-987-23163-0-3 CONTENTS Acronyms and Abbreviations 9 I. FINAL REPORT 11 II. MEASURES, DECISIONS AND RESOLUTIONS 49 A. Measures 51 Measure 1 (2006): Antarctic Specially Protected Areas: Designations and Management Plans 53 Annex A: ASPA No. 116 - New College Valley, Caughley Beach, Cape Bird, Ross Island 57 Annex B: ASPA No. 127 - Haswell Island (Haswell Island and Adjacent Emperor Penguin Rookery on Fast Ice) 69 Annex C: ASPA No. 131 - Canada Glacier, Lake Fryxell, Taylor Valley, Victoria Land 83 Annex D: ASPA No. 134 - Cierva Point and offshore islands, Danco Coast, Antarctic Peninsula 95 Annex E: ASPA No. 136 - Clark Peninsula, Budd Coast, Wilkes Land 105 Annex F: ASPA No. 165 - Edmonson Point, Wood Bay, Ross Sea 119 Annex G: ASPA No. 166 - Port-Martin, Terre Adélie 143 Annex H: ASPA No. 167 - Hawker Island, Vestfold Hills, Ingrid Christensen Coast, Princess Elizabeth Land, East Antarctica 153 Measure 2 (2006): Antarctic Specially Managed Area: Designation and Management Plan: Admiralty Bay, King George Island 167 Annex: Management Plan for ASMA No.
    [Show full text]
  • Final Report of the Thirty-Sixth Antarctic Treaty Consultative Meeting
    Measure 14 (2013) Annex Management Plan for Antarctic Specially Protected Area No 160 FRAZIER ISLANDS, WINDMILL ISLANDS, WILKES LAND, EAST ANTARCTICA Introduction The Frazier Islands consists of a group of three islands located approximately 16 km offshore from Australia’s Casey station, in East Antarctica (see Map A). The islands support the largest of only four known breeding colonies of southern giant petrels Macronectes giganteus on continental Antarctica, and were designated as an Antarctic Specially Protected Area under Measure 2 (2003) for the sanctuary of the birds. The management plan for the Area was revised under Measure 13 (2008). Following their discovery in 1955, the southern giant petrel colonies at the Frazier Islands were visited intermittently during the period mid-January to late March. The aim of these visits was usually the banding of southern giant petrel chicks. Weather permitting, counts of the chicks present were made but were often restricted to Nelly Island. Thus, the early data available do not offer the information needed for an analysis of possible changes in the status of the total population. In more recent years, occupied nests were counted in December, usually covering all three islands. The indication is that the breeding population, especially at Dewart Island, may be increasing. Apart from visits for seabird observations, the Frazier Islands have been visited very infrequently. On average a visit for seabird observations have occurred every two years since the late 1950s (see Appendix 1). In the mid-1980s, a formal management strategy was implemented to minimise human disturbance to breeding colonies of southern giant petrels in the vicinity of Australia’s Antarctic stations.
    [Show full text]