A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands
Fifteen samples of very low-grade mudstones from two widely separated sections in the Miers Bluff Formation on Hurd Peninsula yield an Rb-Sr errorchron (MSWD=8.9) corresponding to an age of 243 ± 8 Ma. This age is interpreted as representing effective homogenization, on a kilometres scale, during tu...
Published in: | Antarctic Science |
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Cambridge University Press (CUP)
1994
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Online Access: | http://dx.doi.org/10.1017/s095410209400060x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S095410209400060X |
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crcambridgeupr:10.1017/s095410209400060x 2024-03-17T08:54:51+00:00 A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands Willan, R. C. R. Pankhurst, R. J. Hervé, F. 1994 http://dx.doi.org/10.1017/s095410209400060x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S095410209400060X en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 6, issue 3, page 401-408 ISSN 0954-1020 1365-2079 Geology Ecology, Evolution, Behavior and Systematics Oceanography journal-article 1994 crcambridgeupr https://doi.org/10.1017/s095410209400060x 2024-02-20T00:00:58Z Fifteen samples of very low-grade mudstones from two widely separated sections in the Miers Bluff Formation on Hurd Peninsula yield an Rb-Sr errorchron (MSWD=8.9) corresponding to an age of 243 ± 8 Ma. This age is interpreted as representing effective homogenization, on a kilometres scale, during turbidite deposition and diagenesis in early Triassic times. The initial 87 Sr/ 86 Sr ratio 0.7085 ± 0.0003 represents a mature crustal source and is consistent with the re-working of material comparable to that eroded from the Chilean fore-arc accretionary complex. Four further samples, collected near to a zone of quartz-carbonate veins, lie to the right of the errorchron, with two samples having unusually low Sr contents. These samples fall on a 113 Ma reference line and indicate metasomatic disturbance in Cretaceous times. Metasomatism was probably related to hydrothermal alteration accompanying widespread silicification and quartz veining on western Hurd Peninsula. A mid-to late Cretaceous age for metasomatic disturbance agrees with field relations which indicate that the hydrothermal activity preceded or was coeval with the mid- to late Cretaceous period of volcanism on Livingston Island. Hence the hydrothermal rocks are not related to the Eocene Barnard Point pluton, as previously suggested. Article in Journal/Newspaper Antarctic Science Livingston Island South Shetland Islands Cambridge University Press South Shetland Islands Livingston Island ENVELOPE(-60.500,-60.500,-62.600,-62.600) Miers ENVELOPE(163.850,163.850,-78.100,-78.100) Hurd ENVELOPE(-60.366,-60.366,-62.682,-62.682) Hurd peninsula ENVELOPE(-60.366,-60.366,-62.676,-62.676) Miers Bluff ENVELOPE(-60.438,-60.438,-62.720,-62.720) Antarctic Science 6 3 401 408 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
spellingShingle |
Geology Ecology, Evolution, Behavior and Systematics Oceanography Willan, R. C. R. Pankhurst, R. J. Hervé, F. A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
topic_facet |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
description |
Fifteen samples of very low-grade mudstones from two widely separated sections in the Miers Bluff Formation on Hurd Peninsula yield an Rb-Sr errorchron (MSWD=8.9) corresponding to an age of 243 ± 8 Ma. This age is interpreted as representing effective homogenization, on a kilometres scale, during turbidite deposition and diagenesis in early Triassic times. The initial 87 Sr/ 86 Sr ratio 0.7085 ± 0.0003 represents a mature crustal source and is consistent with the re-working of material comparable to that eroded from the Chilean fore-arc accretionary complex. Four further samples, collected near to a zone of quartz-carbonate veins, lie to the right of the errorchron, with two samples having unusually low Sr contents. These samples fall on a 113 Ma reference line and indicate metasomatic disturbance in Cretaceous times. Metasomatism was probably related to hydrothermal alteration accompanying widespread silicification and quartz veining on western Hurd Peninsula. A mid-to late Cretaceous age for metasomatic disturbance agrees with field relations which indicate that the hydrothermal activity preceded or was coeval with the mid- to late Cretaceous period of volcanism on Livingston Island. Hence the hydrothermal rocks are not related to the Eocene Barnard Point pluton, as previously suggested. |
format |
Article in Journal/Newspaper |
author |
Willan, R. C. R. Pankhurst, R. J. Hervé, F. |
author_facet |
Willan, R. C. R. Pankhurst, R. J. Hervé, F. |
author_sort |
Willan, R. C. R. |
title |
A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
title_short |
A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
title_full |
A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
title_fullStr |
A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
title_full_unstemmed |
A probable Early Triassic age for the Miers Bluff Formation, Livingston Island, South Shetland Islands |
title_sort |
probable early triassic age for the miers bluff formation, livingston island, south shetland islands |
publisher |
Cambridge University Press (CUP) |
publishDate |
1994 |
url |
http://dx.doi.org/10.1017/s095410209400060x https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S095410209400060X |
long_lat |
ENVELOPE(-60.500,-60.500,-62.600,-62.600) ENVELOPE(163.850,163.850,-78.100,-78.100) ENVELOPE(-60.366,-60.366,-62.682,-62.682) ENVELOPE(-60.366,-60.366,-62.676,-62.676) ENVELOPE(-60.438,-60.438,-62.720,-62.720) |
geographic |
South Shetland Islands Livingston Island Miers Hurd Hurd peninsula Miers Bluff |
geographic_facet |
South Shetland Islands Livingston Island Miers Hurd Hurd peninsula Miers Bluff |
genre |
Antarctic Science Livingston Island South Shetland Islands |
genre_facet |
Antarctic Science Livingston Island South Shetland Islands |
op_source |
Antarctic Science volume 6, issue 3, page 401-408 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s095410209400060x |
container_title |
Antarctic Science |
container_volume |
6 |
container_issue |
3 |
container_start_page |
401 |
op_container_end_page |
408 |
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1793773369876807680 |