Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record
West Antarctica hosts one of the largest continental rift systems on earth. Due to the extensive ice cover and the lack of exposed sedimentary rocks, little is known about the detailed geological and climatic evolution of West Antarc- tica. Here we present initial geochronologic, petrographic, strat...
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Geophysical Research Abstracts, Vol. 21
2019
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ftawi:oai:epic.awi.de:49784 2024-09-15T17:39:06+00:00 Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record Zundel, Maximilian Spiegel, Cornelia Mark, Chris Chew, David Najman, Yani Hillenbrand, C.-D. Ehrmann, Werner Salzmann, Ulrich Klages, Johann Philipp Kuhn, Gerhard Gohl, Karsten 2019 https://epic.awi.de/id/eprint/49784/ https://meetingorganizer.copernicus.org/EGU2019/EGU2019-18920-2.pdf https://hdl.handle.net/10013/epic.ca0caf4d-f2f2-4cd7-a4ef-563c6eab5d05 unknown Geophysical Research Abstracts, Vol. 21 Zundel, M. , Spiegel, C. , Mark, C. , Chew, D. , Najman, Y. , Hillenbrand, C. D. , Ehrmann, W. , Salzmann, U. , Klages, J. P. , Kuhn, G. orcid:0000-0001-6069-7485 and Gohl, K. orcid:0000-0002-9558-2116 (2019) Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record , EGU General Assembly 2019, Vienna, Austria, 7 April 2019 - 12 April 2019 . hdl:10013/epic.ca0caf4d-f2f2-4cd7-a4ef-563c6eab5d05 EPIC3EGU General Assembly 2019, Vienna, Austria, 2019-04-07-2019-04-12Geophysical Research Abstracts, Vol. 21 Conference notRev 2019 ftawi 2024-06-24T04:22:11Z West Antarctica hosts one of the largest continental rift systems on earth. Due to the extensive ice cover and the lack of exposed sedimentary rocks, little is known about the detailed geological and climatic evolution of West Antarc- tica. Here we present initial geochronologic, petrographic, stratigraphic, palynologic and clay mineralogy data of the first drill cores from the Amundsen Sea, off West Antarctica. The drilled succession revealed fine-grained, plant- bearing sediments of late Cretaceous age (∼93 to 85 Ma), deposited during continental stretching and breakup between West Antarctica and New Zealand. The Cretaceous deposits are separated by a peat layer from coarse- grained sandstones, which contain zircon and apatite yielding U-Pb ages of ca. 46-39 Ma. This implies a hiatus of at least 40 Myr between the fine-grained Cretaceous deposits and the overlying sandstones, which is in agreement with the absence of in-situ or reworked Paleocene to early/mid-Eocene palynomorphs. We tentatively interpret this hiatus as reflecting tectonic quiescence and slow downwearing, or non-deposition. This interpretation supports our previous thermochronological data from the onshore realm, which show that extension-related exhumation ceased at the end of the Cretaceous. We interpret renewed deposition during the upper Eocene to Oligocene to reflect renewed rapid exhumation along the West Antarctic Rift System and the rise of the Transantarctic Mountains. As well as the Eocene dates, the Eocene to Oligocene sandstones contain Cambro-Silurian, Permo-Triassic, Early Jurassic and Cretaceous apatite U-Pb age groups, which we interpret as derived from the Transantarctic Moun- tains (igneous and metamorphic rocks of the Cambro-Ordovician Ross Orogeny, and volcanic rocks related to the Early Jurassic Ferrar volcanic event) and Marie Byrd Land / West Antarctica (Permo-Triassic magmatic arc and widespread Cretaceous batholiths). Unusual for this kind of lithology, the sandstones’ apatite yield is low, and lattice defects of ... Conference Object Amundsen Sea Antarc* Antarctic Antarctica Marie Byrd Land West Antarctica Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
West Antarctica hosts one of the largest continental rift systems on earth. Due to the extensive ice cover and the lack of exposed sedimentary rocks, little is known about the detailed geological and climatic evolution of West Antarc- tica. Here we present initial geochronologic, petrographic, stratigraphic, palynologic and clay mineralogy data of the first drill cores from the Amundsen Sea, off West Antarctica. The drilled succession revealed fine-grained, plant- bearing sediments of late Cretaceous age (∼93 to 85 Ma), deposited during continental stretching and breakup between West Antarctica and New Zealand. The Cretaceous deposits are separated by a peat layer from coarse- grained sandstones, which contain zircon and apatite yielding U-Pb ages of ca. 46-39 Ma. This implies a hiatus of at least 40 Myr between the fine-grained Cretaceous deposits and the overlying sandstones, which is in agreement with the absence of in-situ or reworked Paleocene to early/mid-Eocene palynomorphs. We tentatively interpret this hiatus as reflecting tectonic quiescence and slow downwearing, or non-deposition. This interpretation supports our previous thermochronological data from the onshore realm, which show that extension-related exhumation ceased at the end of the Cretaceous. We interpret renewed deposition during the upper Eocene to Oligocene to reflect renewed rapid exhumation along the West Antarctic Rift System and the rise of the Transantarctic Mountains. As well as the Eocene dates, the Eocene to Oligocene sandstones contain Cambro-Silurian, Permo-Triassic, Early Jurassic and Cretaceous apatite U-Pb age groups, which we interpret as derived from the Transantarctic Moun- tains (igneous and metamorphic rocks of the Cambro-Ordovician Ross Orogeny, and volcanic rocks related to the Early Jurassic Ferrar volcanic event) and Marie Byrd Land / West Antarctica (Permo-Triassic magmatic arc and widespread Cretaceous batholiths). Unusual for this kind of lithology, the sandstones’ apatite yield is low, and lattice defects of ... |
format |
Conference Object |
author |
Zundel, Maximilian Spiegel, Cornelia Mark, Chris Chew, David Najman, Yani Hillenbrand, C.-D. Ehrmann, Werner Salzmann, Ulrich Klages, Johann Philipp Kuhn, Gerhard Gohl, Karsten |
spellingShingle |
Zundel, Maximilian Spiegel, Cornelia Mark, Chris Chew, David Najman, Yani Hillenbrand, C.-D. Ehrmann, Werner Salzmann, Ulrich Klages, Johann Philipp Kuhn, Gerhard Gohl, Karsten Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
author_facet |
Zundel, Maximilian Spiegel, Cornelia Mark, Chris Chew, David Najman, Yani Hillenbrand, C.-D. Ehrmann, Werner Salzmann, Ulrich Klages, Johann Philipp Kuhn, Gerhard Gohl, Karsten |
author_sort |
Zundel, Maximilian |
title |
Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
title_short |
Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
title_full |
Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
title_fullStr |
Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
title_full_unstemmed |
Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record |
title_sort |
insights into the tectonic and climatic evolution of west antarctica from the amundsen sea sediment record |
publisher |
Geophysical Research Abstracts, Vol. 21 |
publishDate |
2019 |
url |
https://epic.awi.de/id/eprint/49784/ https://meetingorganizer.copernicus.org/EGU2019/EGU2019-18920-2.pdf https://hdl.handle.net/10013/epic.ca0caf4d-f2f2-4cd7-a4ef-563c6eab5d05 |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Marie Byrd Land West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Marie Byrd Land West Antarctica |
op_source |
EPIC3EGU General Assembly 2019, Vienna, Austria, 2019-04-07-2019-04-12Geophysical Research Abstracts, Vol. 21 |
op_relation |
Zundel, M. , Spiegel, C. , Mark, C. , Chew, D. , Najman, Y. , Hillenbrand, C. D. , Ehrmann, W. , Salzmann, U. , Klages, J. P. , Kuhn, G. orcid:0000-0001-6069-7485 and Gohl, K. orcid:0000-0002-9558-2116 (2019) Insights into the tectonic and climatic evolution of West Antarctica from the Amundsen Sea sediment record , EGU General Assembly 2019, Vienna, Austria, 7 April 2019 - 12 April 2019 . hdl:10013/epic.ca0caf4d-f2f2-4cd7-a4ef-563c6eab5d05 |
_version_ |
1810477537686454272 |