The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge
Summary Late Triassic Radiolaria have been recovered from a bedded chert collected early in 1977 in the South Orkney islands. This is the first reliable palaeontological evidence for the age of the so-called basement complex that forms most of the exposed rock of a microcontinent on the southern lim...
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Cambridge University Press (CUP)
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crcambridgeupr:10.1017/s0016756800024766 2024-03-03T08:48:48+00:00 The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge Dalziel, I. W. D. Elliot, D. H. Jones, D. L. Thomson, J. W. Thomson, M. R. A. Wells, N. A. Zinsmeister, W. J. 1981 http://dx.doi.org/10.1017/s0016756800024766 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800024766 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Geological Magazine volume 118, issue 1, page 15-25 ISSN 0016-7568 1469-5081 Geology journal-article 1981 crcambridgeupr https://doi.org/10.1017/s0016756800024766 2024-02-08T08:30:13Z Summary Late Triassic Radiolaria have been recovered from a bedded chert collected early in 1977 in the South Orkney islands. This is the first reliable palaeontological evidence for the age of the so-called basement complex that forms most of the exposed rock of a microcontinent on the southern limb of the Scotia Ridge. The fossils place a lower limit on the age of deformation of at least part of the complex as post-Karnian or Norian. The basement is overlain by undeformed Jurassic to Cretaceous conglomerates, which suggests this event took place during the early Mesozoic Gondwanian orogeny. The new data are consistent with the interpretation that the basement complex of the South Orkney Islands represents part of a subduction complex and was accreted to the Pacific margin of Gondwanaland during the late Triassic or early Jurassic time. Article in Journal/Newspaper South Orkney Islands Cambridge University Press Pacific South Orkney Islands ENVELOPE(-45.500,-45.500,-60.583,-60.583) Geological Magazine 118 1 15 25 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
topic |
Geology |
spellingShingle |
Geology Dalziel, I. W. D. Elliot, D. H. Jones, D. L. Thomson, J. W. Thomson, M. R. A. Wells, N. A. Zinsmeister, W. J. The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
topic_facet |
Geology |
description |
Summary Late Triassic Radiolaria have been recovered from a bedded chert collected early in 1977 in the South Orkney islands. This is the first reliable palaeontological evidence for the age of the so-called basement complex that forms most of the exposed rock of a microcontinent on the southern limb of the Scotia Ridge. The fossils place a lower limit on the age of deformation of at least part of the complex as post-Karnian or Norian. The basement is overlain by undeformed Jurassic to Cretaceous conglomerates, which suggests this event took place during the early Mesozoic Gondwanian orogeny. The new data are consistent with the interpretation that the basement complex of the South Orkney Islands represents part of a subduction complex and was accreted to the Pacific margin of Gondwanaland during the late Triassic or early Jurassic time. |
format |
Article in Journal/Newspaper |
author |
Dalziel, I. W. D. Elliot, D. H. Jones, D. L. Thomson, J. W. Thomson, M. R. A. Wells, N. A. Zinsmeister, W. J. |
author_facet |
Dalziel, I. W. D. Elliot, D. H. Jones, D. L. Thomson, J. W. Thomson, M. R. A. Wells, N. A. Zinsmeister, W. J. |
author_sort |
Dalziel, I. W. D. |
title |
The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
title_short |
The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
title_full |
The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
title_fullStr |
The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
title_full_unstemmed |
The geological significance of some Triassic microfossils from the South Orkney Islands, Scotia Ridge |
title_sort |
geological significance of some triassic microfossils from the south orkney islands, scotia ridge |
publisher |
Cambridge University Press (CUP) |
publishDate |
1981 |
url |
http://dx.doi.org/10.1017/s0016756800024766 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800024766 |
long_lat |
ENVELOPE(-45.500,-45.500,-60.583,-60.583) |
geographic |
Pacific South Orkney Islands |
geographic_facet |
Pacific South Orkney Islands |
genre |
South Orkney Islands |
genre_facet |
South Orkney Islands |
op_source |
Geological Magazine volume 118, issue 1, page 15-25 ISSN 0016-7568 1469-5081 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0016756800024766 |
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Geological Magazine |
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118 |
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1 |
container_start_page |
15 |
op_container_end_page |
25 |
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1792505824477708288 |