Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica
Within the Jones Mountains, which form part of the Thurston Island crustal block, up to 700 m of Miocene (c. 10 Ma) pillow basalt and palagonitized volcaniclastic rocks unconformably overlie Jurassic granitic basement and Cretaceous volcanic rocks and dykes. New geochemical analyses demonstrate the...
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Cambridge University Press
1994
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ftnerc:oai:nora.nerc.ac.uk:516520 2023-05-15T13:49:33+02:00 Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica Hole, M. J. Storey, B. C. LeMasurier, W. E. 1994-03 http://nora.nerc.ac.uk/id/eprint/516520/ https://doi.org/10.1017/S0954102094000118 unknown Cambridge University Press Hole, M. J.; Storey, B. C.; LeMasurier, W. E. 1994 Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica. Antarctic Science, 6 (1). 85-92. https://doi.org/10.1017/S0954102094000118 <https://doi.org/10.1017/S0954102094000118> Publication - Article PeerReviewed 1994 ftnerc https://doi.org/10.1017/S0954102094000118 2023-02-04T19:44:39Z Within the Jones Mountains, which form part of the Thurston Island crustal block, up to 700 m of Miocene (c. 10 Ma) pillow basalt and palagonitized volcaniclastic rocks unconformably overlie Jurassic granitic basement and Cretaceous volcanic rocks and dykes. New geochemical analyses demonstrate the alkalic nature of the basalts, which range in composition from alkali basalt to basanite. Unradiogenic Sr-isotope ratios (0.7031–0.7034), coupled with low LILE/HFSE ratios (e.g. Th/Ta c. 1.4, Rb/Nb 0.3–0.9) indicate a predominantly asthenospheric source for the basalts. The Jones Mountains basalts are geochemically similar to the alkalic basalts of Marie Byrd Land, but have consistently lower K/Ba and higher Ba/Nb ratios than Late Cenozoic alkalic basalts along the Antarctic Peninsula. These regional variations in geochemical composition apparently reflect differences in tectonic setting and are not the result of lithospheric interaction or partial melting/crystallization effects. The generation of alkalic magmas along the Antarctic Peninsula was causally related to the formation of slab windows following ridge crest-trench collision and the cessation of subduction, whereas the Jones Mountains alkalic basalts may represent the expression of the northward propagation of the head of the Marie Byrd Land plume. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica Marie Byrd Land Thurston Island West Antarctica Natural Environment Research Council: NERC Open Research Archive Antarctic The Antarctic Antarctic Peninsula West Antarctica Byrd Marie Byrd Land ENVELOPE(-130.000,-130.000,-78.000,-78.000) Thurston ENVELOPE(-97.500,-97.500,-71.833,-71.833) Thurston Island ENVELOPE(-99.000,-99.000,-72.167,-72.167) Jones Mountains ENVELOPE(-94.000,-94.000,-73.667,-73.667) Antarctic Science 6 1 85 92 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
Within the Jones Mountains, which form part of the Thurston Island crustal block, up to 700 m of Miocene (c. 10 Ma) pillow basalt and palagonitized volcaniclastic rocks unconformably overlie Jurassic granitic basement and Cretaceous volcanic rocks and dykes. New geochemical analyses demonstrate the alkalic nature of the basalts, which range in composition from alkali basalt to basanite. Unradiogenic Sr-isotope ratios (0.7031–0.7034), coupled with low LILE/HFSE ratios (e.g. Th/Ta c. 1.4, Rb/Nb 0.3–0.9) indicate a predominantly asthenospheric source for the basalts. The Jones Mountains basalts are geochemically similar to the alkalic basalts of Marie Byrd Land, but have consistently lower K/Ba and higher Ba/Nb ratios than Late Cenozoic alkalic basalts along the Antarctic Peninsula. These regional variations in geochemical composition apparently reflect differences in tectonic setting and are not the result of lithospheric interaction or partial melting/crystallization effects. The generation of alkalic magmas along the Antarctic Peninsula was causally related to the formation of slab windows following ridge crest-trench collision and the cessation of subduction, whereas the Jones Mountains alkalic basalts may represent the expression of the northward propagation of the head of the Marie Byrd Land plume. |
format |
Article in Journal/Newspaper |
author |
Hole, M. J. Storey, B. C. LeMasurier, W. E. |
spellingShingle |
Hole, M. J. Storey, B. C. LeMasurier, W. E. Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
author_facet |
Hole, M. J. Storey, B. C. LeMasurier, W. E. |
author_sort |
Hole, M. J. |
title |
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
title_short |
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
title_full |
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
title_fullStr |
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
title_full_unstemmed |
Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica |
title_sort |
tectonic setting and geochemistry of miocene alkalic basalts from the jones mountains, west antarctica |
publisher |
Cambridge University Press |
publishDate |
1994 |
url |
http://nora.nerc.ac.uk/id/eprint/516520/ https://doi.org/10.1017/S0954102094000118 |
long_lat |
ENVELOPE(-130.000,-130.000,-78.000,-78.000) ENVELOPE(-97.500,-97.500,-71.833,-71.833) ENVELOPE(-99.000,-99.000,-72.167,-72.167) ENVELOPE(-94.000,-94.000,-73.667,-73.667) |
geographic |
Antarctic The Antarctic Antarctic Peninsula West Antarctica Byrd Marie Byrd Land Thurston Thurston Island Jones Mountains |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula West Antarctica Byrd Marie Byrd Land Thurston Thurston Island Jones Mountains |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica Marie Byrd Land Thurston Island West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctic Science Antarctica Marie Byrd Land Thurston Island West Antarctica |
op_relation |
Hole, M. J.; Storey, B. C.; LeMasurier, W. E. 1994 Tectonic setting and geochemistry of Miocene alkalic basalts from the Jones Mountains, West Antarctica. Antarctic Science, 6 (1). 85-92. https://doi.org/10.1017/S0954102094000118 <https://doi.org/10.1017/S0954102094000118> |
op_doi |
https://doi.org/10.1017/S0954102094000118 |
container_title |
Antarctic Science |
container_volume |
6 |
container_issue |
1 |
container_start_page |
85 |
op_container_end_page |
92 |
_version_ |
1766251649211301888 |