Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula
Abstract We report and describe two new small diamictite outcrops on Isla Marambio (Seymour Island), Antarctic Peninsula. These rocks rest on an erosional unconformity on top of the Eocene La Meseta Formation and are unconformably covered by glaciomarine rocks of the ?Pliocene–Pleistocene Weddell Se...
Published in: | Antarctic Science |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
2009
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0954102009990629 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102009990629 |
id |
crcambridgeupr:10.1017/s0954102009990629 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0954102009990629 2024-09-15T17:48:40+00:00 Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula Marenssi, Sergio A. Casadío, Silvio Santillana, Sergio N. 2009 http://dx.doi.org/10.1017/s0954102009990629 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102009990629 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 22, issue 2, page 193-198 ISSN 0954-1020 1365-2079 journal-article 2009 crcambridgeupr https://doi.org/10.1017/s0954102009990629 2024-07-31T04:04:10Z Abstract We report and describe two new small diamictite outcrops on Isla Marambio (Seymour Island), Antarctic Peninsula. These rocks rest on an erosional unconformity on top of the Eocene La Meseta Formation and are unconformably covered by glaciomarine rocks of the ?Pliocene–Pleistocene Weddell Sea Formation. The lithology, fossil content and isotopic ages obtained strongly suggest that the rocks belong to the Hobbs Glacier Formation and support a Late Miocene age for this unit. Additionally, the dated basalt clast provides the oldest age (12.4 Ma) for the James Ross Island Volcanic Group recorded up to now. The here described diamictite cannot be confidently correlated with a glaciomarine unit previously assigned to the Late Eocene–Lower Oligocene taken as proof that initial expansion of ice on Antarctica encompassed the entire continent synchronously in the earliest Oligocene. However, it is now evident that there are likely to be more, short but important, stratigraphic sequences of key regional and Antarctic wide interest preserved on the plateau of Isla Marambio. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica James Ross Island Ross Island Seymour Island Weddell Sea Cambridge University Press Antarctic Science 22 2 193 198 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract We report and describe two new small diamictite outcrops on Isla Marambio (Seymour Island), Antarctic Peninsula. These rocks rest on an erosional unconformity on top of the Eocene La Meseta Formation and are unconformably covered by glaciomarine rocks of the ?Pliocene–Pleistocene Weddell Sea Formation. The lithology, fossil content and isotopic ages obtained strongly suggest that the rocks belong to the Hobbs Glacier Formation and support a Late Miocene age for this unit. Additionally, the dated basalt clast provides the oldest age (12.4 Ma) for the James Ross Island Volcanic Group recorded up to now. The here described diamictite cannot be confidently correlated with a glaciomarine unit previously assigned to the Late Eocene–Lower Oligocene taken as proof that initial expansion of ice on Antarctica encompassed the entire continent synchronously in the earliest Oligocene. However, it is now evident that there are likely to be more, short but important, stratigraphic sequences of key regional and Antarctic wide interest preserved on the plateau of Isla Marambio. |
format |
Article in Journal/Newspaper |
author |
Marenssi, Sergio A. Casadío, Silvio Santillana, Sergio N. |
spellingShingle |
Marenssi, Sergio A. Casadío, Silvio Santillana, Sergio N. Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
author_facet |
Marenssi, Sergio A. Casadío, Silvio Santillana, Sergio N. |
author_sort |
Marenssi, Sergio A. |
title |
Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
title_short |
Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
title_full |
Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
title_fullStr |
Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
title_full_unstemmed |
Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula |
title_sort |
record of late miocene glacial deposits on isla marambio (seymour island), antarctic peninsula |
publisher |
Cambridge University Press (CUP) |
publishDate |
2009 |
url |
http://dx.doi.org/10.1017/s0954102009990629 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102009990629 |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica James Ross Island Ross Island Seymour Island Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica James Ross Island Ross Island Seymour Island Weddell Sea |
op_source |
Antarctic Science volume 22, issue 2, page 193-198 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0954102009990629 |
container_title |
Antarctic Science |
container_volume |
22 |
container_issue |
2 |
container_start_page |
193 |
op_container_end_page |
198 |
_version_ |
1810290151249674240 |