The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica)
La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known,...
Main Authors: | , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Polish Geological Institute-National Research Institute
2011
|
Subjects: | |
Online Access: | https://gq.pgi.gov.pl/article/view/7727 https://doi.org/10.7306/gq.v55i4.7727 |
id |
ftjgq:oai:geojournals.pgi.gov.pl:article/7727 |
---|---|
record_format |
openpolar |
spelling |
ftjgq:oai:geojournals.pgi.gov.pl:article/7727 2023-05-15T13:35:19+02:00 The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) Tatur, Andrzej Edward Krajewski, Krzysztof Paweł DelValle, Rodolfo Alfredo 2011-12-22 application/pdf https://gq.pgi.gov.pl/article/view/7727 https://doi.org/10.7306/gq.v55i4.7727 eng eng Polish Geological Institute-National Research Institute https://gq.pgi.gov.pl/article/view/7727/pdf_21 Geological Quarterly; Vol 55, No 4 (2011); 345–360 1641-7291 Antarctica Seymour Eocene sediments goethite thanatocoenosis info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2011 ftjgq https://doi.org/10.7306/gq.v55i4.7727 2019-08-13T19:05:53Z La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known, and therefore it has been carefully investigated. The lowest part of the La Meseta Formation, at the southern bank of a palaeodelta, is represented by relics of a prograding sequence of sediments deposited in the wave-dominated part of a deltaic system in the offshore and lower and upper shoreface environments. The sequence is completed landwards by younger tidal plain sediments deposited at 40 m lower altitude in a relatively protected, central estuarine basin, which was dominated by tidal activity and influenced by periodic fluvial inflow. These strata were deposited during a late Paleocene or Ypresian/Lutetian lowstand of sea level, which might reflect a glaciation event or glacioisostatic rebound of land following deglaciation of hypothetic Antarctic inland glaciers. Forced regression of sea level and seaward expansion of a deltaic freshwater environment, led to local extinction of a unique assemblage of marine echinoderms, bryozoans, corals and brachiopods. These marine fossils, representing a thanatocoenosis, are perfectly preserved due to syngenetic goethite permineralisation. This process owed its origin to excess reactive iron coming from sulphide-rich bedrock through weathering processes and acid sulphate drainage of the neighbouring land area. Article in Journal/Newspaper Antarc* Antarctic Antarctica Seymour Island Geological Quarterly Antarctic Seymour ENVELOPE(-56.767,-56.767,-64.283,-64.283) Seymour Island ENVELOPE(-56.750,-56.750,-64.283,-64.283) Southern Bank ENVELOPE(-55.552,-55.552,52.288,52.288) |
institution |
Open Polar |
collection |
Geological Quarterly |
op_collection_id |
ftjgq |
language |
English |
topic |
Antarctica Seymour Eocene sediments goethite thanatocoenosis |
spellingShingle |
Antarctica Seymour Eocene sediments goethite thanatocoenosis Tatur, Andrzej Edward Krajewski, Krzysztof Paweł DelValle, Rodolfo Alfredo The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
topic_facet |
Antarctica Seymour Eocene sediments goethite thanatocoenosis |
description |
La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known, and therefore it has been carefully investigated. The lowest part of the La Meseta Formation, at the southern bank of a palaeodelta, is represented by relics of a prograding sequence of sediments deposited in the wave-dominated part of a deltaic system in the offshore and lower and upper shoreface environments. The sequence is completed landwards by younger tidal plain sediments deposited at 40 m lower altitude in a relatively protected, central estuarine basin, which was dominated by tidal activity and influenced by periodic fluvial inflow. These strata were deposited during a late Paleocene or Ypresian/Lutetian lowstand of sea level, which might reflect a glaciation event or glacioisostatic rebound of land following deglaciation of hypothetic Antarctic inland glaciers. Forced regression of sea level and seaward expansion of a deltaic freshwater environment, led to local extinction of a unique assemblage of marine echinoderms, bryozoans, corals and brachiopods. These marine fossils, representing a thanatocoenosis, are perfectly preserved due to syngenetic goethite permineralisation. This process owed its origin to excess reactive iron coming from sulphide-rich bedrock through weathering processes and acid sulphate drainage of the neighbouring land area. |
format |
Article in Journal/Newspaper |
author |
Tatur, Andrzej Edward Krajewski, Krzysztof Paweł DelValle, Rodolfo Alfredo |
author_facet |
Tatur, Andrzej Edward Krajewski, Krzysztof Paweł DelValle, Rodolfo Alfredo |
author_sort |
Tatur, Andrzej Edward |
title |
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
title_short |
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
title_full |
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
title_fullStr |
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
title_full_unstemmed |
The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica) |
title_sort |
facies and biota of the oldest exposed strata of the eocene la meseta formation (seymour island, antarctica) |
publisher |
Polish Geological Institute-National Research Institute |
publishDate |
2011 |
url |
https://gq.pgi.gov.pl/article/view/7727 https://doi.org/10.7306/gq.v55i4.7727 |
long_lat |
ENVELOPE(-56.767,-56.767,-64.283,-64.283) ENVELOPE(-56.750,-56.750,-64.283,-64.283) ENVELOPE(-55.552,-55.552,52.288,52.288) |
geographic |
Antarctic Seymour Seymour Island Southern Bank |
geographic_facet |
Antarctic Seymour Seymour Island Southern Bank |
genre |
Antarc* Antarctic Antarctica Seymour Island |
genre_facet |
Antarc* Antarctic Antarctica Seymour Island |
op_source |
Geological Quarterly; Vol 55, No 4 (2011); 345–360 1641-7291 |
op_relation |
https://gq.pgi.gov.pl/article/view/7727/pdf_21 |
op_doi |
https://doi.org/10.7306/gq.v55i4.7727 |
_version_ |
1766064165718327296 |