Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica New evidence of Eocene preglacial environments has been found on the southern coast of Ezcurra Inlet on King George Island, South Shetland Islands, West Antarctica. P...
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Walter de Gruyter GmbH
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crdegruyter:10.2478/v10183-012-0002-7 2023-05-15T14:12:11+02:00 Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica Mozer, Anna 2012 http://dx.doi.org/10.2478/v10183-012-0002-7 https://content.sciendo.com/view/journals/popore/33/1/article-p41.xml https://www.degruyter.com/view/j/popore.2012.33.issue-1/v10183-012-0002-7/v10183-012-0002-7.pdf unknown Walter de Gruyter GmbH Polish Polar Research volume 33, issue 1, page 41-62 ISSN 2081-8262 0138-0338 Ecology Ecology, Evolution, Behavior and Systematics journal-article 2012 crdegruyter https://doi.org/10.2478/v10183-012-0002-7 2022-06-16T13:41:06Z Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica New evidence of Eocene preglacial environments has been found on the southern coast of Ezcurra Inlet on King George Island, South Shetland Islands, West Antarctica. Plant remains (trunks, leaves, detritus) and carbonaceous seams and beds occur in sedimentary strata in a 4 km long Cytadela outcrop of the Point Thomas Formation. They are an evidence for the presence and diversity of terrestrial vegetation in the northern Antarctic Peninsula region. The forests were composed mostly of Podocarpaceae- Araucaria-Nothofagus , with an undergrowth of hygrophilous and thermophilous ferns, and grew on volcanic slopes and surrounding lowland areas of King George Island during breaks in volcanic activity. The succession that crops out at Cytadela provides a record of changing climatic conditions from a warm and wet climate with extensive vegetation to a much drier climate with limited vegetation and ubiquitous weathering of volcanic bedrock. The geochemical indices of weathering (CIA, PIA and CIW) have narrow and relatively high value ranges (76-88), suggesting moderate to high chemical weathering under warm and humid climate conditions. The decrease in humidity and the decline in plant life through the succession can be related to the gradually cooling climate preceding development of the Oligocene ice cover across the Antarctic continent. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica King George Island Polar Research South Shetland Islands West Antarctica De Gruyter (via Crossref) Antarctic The Antarctic Antarctic Peninsula King George Island West Antarctica South Shetland Islands Admiralty Bay Ezcurra ENVELOPE(-58.535,-58.535,-62.162,-62.162) Ezcurra Inlet ENVELOPE(-58.567,-58.567,-62.167,-62.167) Point Thomas ENVELOPE(-58.500,-58.500,-62.167,-62.167) Cytadela ENVELOPE(-58.583,-58.583,-62.183,-62.183) Polish Polar Research 33 1 41 62 |
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Open Polar |
collection |
De Gruyter (via Crossref) |
op_collection_id |
crdegruyter |
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unknown |
topic |
Ecology Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Ecology Ecology, Evolution, Behavior and Systematics Mozer, Anna Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
topic_facet |
Ecology Ecology, Evolution, Behavior and Systematics |
description |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica New evidence of Eocene preglacial environments has been found on the southern coast of Ezcurra Inlet on King George Island, South Shetland Islands, West Antarctica. Plant remains (trunks, leaves, detritus) and carbonaceous seams and beds occur in sedimentary strata in a 4 km long Cytadela outcrop of the Point Thomas Formation. They are an evidence for the presence and diversity of terrestrial vegetation in the northern Antarctic Peninsula region. The forests were composed mostly of Podocarpaceae- Araucaria-Nothofagus , with an undergrowth of hygrophilous and thermophilous ferns, and grew on volcanic slopes and surrounding lowland areas of King George Island during breaks in volcanic activity. The succession that crops out at Cytadela provides a record of changing climatic conditions from a warm and wet climate with extensive vegetation to a much drier climate with limited vegetation and ubiquitous weathering of volcanic bedrock. The geochemical indices of weathering (CIA, PIA and CIW) have narrow and relatively high value ranges (76-88), suggesting moderate to high chemical weathering under warm and humid climate conditions. The decrease in humidity and the decline in plant life through the succession can be related to the gradually cooling climate preceding development of the Oligocene ice cover across the Antarctic continent. |
format |
Article in Journal/Newspaper |
author |
Mozer, Anna |
author_facet |
Mozer, Anna |
author_sort |
Mozer, Anna |
title |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
title_short |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
title_full |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
title_fullStr |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
title_full_unstemmed |
Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica |
title_sort |
pre-glacial sedimentary facies of the point thomas formation (eocene) at cytadela, admiralty bay, king george island, west antarctica |
publisher |
Walter de Gruyter GmbH |
publishDate |
2012 |
url |
http://dx.doi.org/10.2478/v10183-012-0002-7 https://content.sciendo.com/view/journals/popore/33/1/article-p41.xml https://www.degruyter.com/view/j/popore.2012.33.issue-1/v10183-012-0002-7/v10183-012-0002-7.pdf |
long_lat |
ENVELOPE(-58.535,-58.535,-62.162,-62.162) ENVELOPE(-58.567,-58.567,-62.167,-62.167) ENVELOPE(-58.500,-58.500,-62.167,-62.167) ENVELOPE(-58.583,-58.583,-62.183,-62.183) |
geographic |
Antarctic The Antarctic Antarctic Peninsula King George Island West Antarctica South Shetland Islands Admiralty Bay Ezcurra Ezcurra Inlet Point Thomas Cytadela |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula King George Island West Antarctica South Shetland Islands Admiralty Bay Ezcurra Ezcurra Inlet Point Thomas Cytadela |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica King George Island Polar Research South Shetland Islands West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica King George Island Polar Research South Shetland Islands West Antarctica |
op_source |
Polish Polar Research volume 33, issue 1, page 41-62 ISSN 2081-8262 0138-0338 |
op_doi |
https://doi.org/10.2478/v10183-012-0002-7 |
container_title |
Polish Polar Research |
container_volume |
33 |
container_issue |
1 |
container_start_page |
41 |
op_container_end_page |
62 |
_version_ |
1766284456777220096 |