Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica
The Cretaceous Fossil Bluff Group on Alexander Island, on the west side of the Antarctic Peninsula, contains a remarkably complete record of the evolution of a forearc basin. The latest (Aptian-Albian) stages in the basin history are recorded in a well-exposed succession at the southern end of the i...
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Cambridge University Press
2002
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ftnerc:oai:nora.nerc.ac.uk:13598 2023-05-15T13:15:16+02:00 Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica Nichols, Gary J. Cantrill, David J. 2002 http://nora.nerc.ac.uk/id/eprint/13598/ unknown Cambridge University Press Nichols, Gary J.; Cantrill, David J. 2002 Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica. Geological Magazine, 139 (3). 313-330. https://doi.org/10.1017/S0016756802006465 <https://doi.org/10.1017/S0016756802006465> Earth Sciences Publication - Article PeerReviewed 2002 ftnerc https://doi.org/10.1017/S0016756802006465 2023-02-04T19:28:43Z The Cretaceous Fossil Bluff Group on Alexander Island, on the west side of the Antarctic Peninsula, contains a remarkably complete record of the evolution of a forearc basin. The latest (Aptian-Albian) stages in the basin history are recorded in a well-exposed succession at the southern end of the island, where a series of nunataks provide exposure of over a thousand metres of shallow marine and continental deposits. An abrupt facies shift from upper shoreface marine facies to braided fluvial deposits is interpreted as the record of regional uplift in the volcanic arc. This event coincides with the Palmer Land deformation event which may be related to a mid-Cretaceous mantle plume A gradual reduction in depositional gradient and a return to shallow marine conditions towards the top of the exposed section is interpreted as a consequence of erosion of the arc and subsidence within the basin. Palaeocurrent data and facies distributions indicate that the continental deposits formed a fan-shaped wedge at least 30 km in diameter in the southern part of the forearc basin. Fossil plants indicate that the palaeoclimate was warm and humid throughout the period of deposition. Mapping and facics analysis of the upper part of the Fossil Bluff Group in southern Alexander Island has resulted in a revision of the stratigraphic terminology for the area. The Triton Point Member, formerly part of the Neptune Glacier Formation, has been raised to formation status and two members (the Citadel Bastion Member and the Coal Nunatak Member) and a Bed (the Upper Coal Nunatak Sandstone Bed) are defined here within the formation. Article in Journal/Newspaper Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica Neptune Glacier Palmer Land Natural Environment Research Council: NERC Open Research Archive Alexander Island ENVELOPE(-69.895,-69.895,-71.287,-71.287) Antarctic Antarctic Peninsula Citadel Bastion ENVELOPE(-68.525,-68.525,-71.988,-71.988) Coal nunatak ENVELOPE(-68.534,-68.534,-72.071,-72.071) Fossil Bluff ENVELOPE(-68.274,-68.274,-71.332,-71.332) Neptune Glacier ENVELOPE(-68.473,-68.473,-71.713,-71.713) Palmer Land ENVELOPE(-65.000,-65.000,-71.500,-71.500) The Antarctic The Citadel ENVELOPE(-62.648,-62.648,58.550,58.550) Triton ENVELOPE(-55.615,-55.615,49.517,49.517) Triton Point ENVELOPE(-68.213,-68.213,-71.690,-71.690) Geological Magazine 139 3 313 330 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Nichols, Gary J. Cantrill, David J. Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
topic_facet |
Earth Sciences |
description |
The Cretaceous Fossil Bluff Group on Alexander Island, on the west side of the Antarctic Peninsula, contains a remarkably complete record of the evolution of a forearc basin. The latest (Aptian-Albian) stages in the basin history are recorded in a well-exposed succession at the southern end of the island, where a series of nunataks provide exposure of over a thousand metres of shallow marine and continental deposits. An abrupt facies shift from upper shoreface marine facies to braided fluvial deposits is interpreted as the record of regional uplift in the volcanic arc. This event coincides with the Palmer Land deformation event which may be related to a mid-Cretaceous mantle plume A gradual reduction in depositional gradient and a return to shallow marine conditions towards the top of the exposed section is interpreted as a consequence of erosion of the arc and subsidence within the basin. Palaeocurrent data and facies distributions indicate that the continental deposits formed a fan-shaped wedge at least 30 km in diameter in the southern part of the forearc basin. Fossil plants indicate that the palaeoclimate was warm and humid throughout the period of deposition. Mapping and facics analysis of the upper part of the Fossil Bluff Group in southern Alexander Island has resulted in a revision of the stratigraphic terminology for the area. The Triton Point Member, formerly part of the Neptune Glacier Formation, has been raised to formation status and two members (the Citadel Bastion Member and the Coal Nunatak Member) and a Bed (the Upper Coal Nunatak Sandstone Bed) are defined here within the formation. |
format |
Article in Journal/Newspaper |
author |
Nichols, Gary J. Cantrill, David J. |
author_facet |
Nichols, Gary J. Cantrill, David J. |
author_sort |
Nichols, Gary J. |
title |
Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
title_short |
Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
title_full |
Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
title_fullStr |
Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
title_full_unstemmed |
Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica |
title_sort |
tectonic and climatic controls on a mesozoic forearc basin succession, alexander island, antarctica |
publisher |
Cambridge University Press |
publishDate |
2002 |
url |
http://nora.nerc.ac.uk/id/eprint/13598/ |
long_lat |
ENVELOPE(-69.895,-69.895,-71.287,-71.287) ENVELOPE(-68.525,-68.525,-71.988,-71.988) ENVELOPE(-68.534,-68.534,-72.071,-72.071) ENVELOPE(-68.274,-68.274,-71.332,-71.332) ENVELOPE(-68.473,-68.473,-71.713,-71.713) ENVELOPE(-65.000,-65.000,-71.500,-71.500) ENVELOPE(-62.648,-62.648,58.550,58.550) ENVELOPE(-55.615,-55.615,49.517,49.517) ENVELOPE(-68.213,-68.213,-71.690,-71.690) |
geographic |
Alexander Island Antarctic Antarctic Peninsula Citadel Bastion Coal nunatak Fossil Bluff Neptune Glacier Palmer Land The Antarctic The Citadel Triton Triton Point |
geographic_facet |
Alexander Island Antarctic Antarctic Peninsula Citadel Bastion Coal nunatak Fossil Bluff Neptune Glacier Palmer Land The Antarctic The Citadel Triton Triton Point |
genre |
Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica Neptune Glacier Palmer Land |
genre_facet |
Alexander Island Antarc* Antarctic Antarctic Peninsula Antarctica Neptune Glacier Palmer Land |
op_relation |
Nichols, Gary J.; Cantrill, David J. 2002 Tectonic and climatic controls on a Mesozoic forearc basin succession, Alexander Island, Antarctica. Geological Magazine, 139 (3). 313-330. https://doi.org/10.1017/S0016756802006465 <https://doi.org/10.1017/S0016756802006465> |
op_doi |
https://doi.org/10.1017/S0016756802006465 |
container_title |
Geological Magazine |
container_volume |
139 |
container_issue |
3 |
container_start_page |
313 |
op_container_end_page |
330 |
_version_ |
1766267763174670336 |