Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology
Abstract The Rauer Group, in Prydz Bay, contains reworked Archaean-Proterozoic crust in high-strain zones that formed during a pervasive high-temperature ductile deformation event related to intracratonic mechanisms. The effects of this event extend southwards from Prydz Bay into the southern Prince...
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/s0954102007000478 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102007000478 |
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crcambridgeupr:10.1017/s0954102007000478 2024-09-15T17:41:33+00:00 Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology Wilson, Christopher J.L. Quinn, Cameron Tong, Laixi Phillips, David 2007 http://dx.doi.org/10.1017/s0954102007000478 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102007000478 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 19, issue 3, page 339-353 ISSN 0954-1020 1365-2079 journal-article 2007 crcambridgeupr https://doi.org/10.1017/s0954102007000478 2024-08-21T04:04:14Z Abstract The Rauer Group, in Prydz Bay, contains reworked Archaean-Proterozoic crust in high-strain zones that formed during a pervasive high-temperature ductile deformation event related to intracratonic mechanisms. The effects of this event extend southwards from Prydz Bay into the southern Prince Charles Mountains. The associated structural evolution involved development of ductile and brittle structures that formed during an approximately north–south directed transpressional deformation event that is confined to high-grade (>800°C) shear zones in the Rauer Group. Minerals from the Rauer Group, yield 40 Ar/ 39 Ar cooling ages ranging from 560 to 460 Ma. Thermal histories derived from hornblende, biotite and feldspar suggest that the onset of rapid cooling began sometime prior to 510 Ma with cooling rates of c . 42 to 33°C myr -1 from c . 510 Ma to c . 500 Ma. Whereas, 40 Ar/ 39 Ar data obtained from plagioclase and K–feldspar suggest a slower cooling from c . 500 Ma to c . 460 Ma with cooling rates from 5 to 2°C myr -1 . These results demonstrate that the early Palaeozoic cooling history and comparable palaeostress regimes are regionally extensive, which has important implications for the tectonothermal and stress-field variability across Gondwana. The elevated thermal conditions would induce lithospheric weakening and promote the early Palaeozoic intraplate orogeny observed in eastern Antarctica with the development of a large intracratonic shear system. Article in Journal/Newspaper Antarc* Antarctic Science Antarctica East Antarctica Prince Charles Mountains Prydz Bay Cambridge University Press Antarctic Science 19 3 339 353 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract The Rauer Group, in Prydz Bay, contains reworked Archaean-Proterozoic crust in high-strain zones that formed during a pervasive high-temperature ductile deformation event related to intracratonic mechanisms. The effects of this event extend southwards from Prydz Bay into the southern Prince Charles Mountains. The associated structural evolution involved development of ductile and brittle structures that formed during an approximately north–south directed transpressional deformation event that is confined to high-grade (>800°C) shear zones in the Rauer Group. Minerals from the Rauer Group, yield 40 Ar/ 39 Ar cooling ages ranging from 560 to 460 Ma. Thermal histories derived from hornblende, biotite and feldspar suggest that the onset of rapid cooling began sometime prior to 510 Ma with cooling rates of c . 42 to 33°C myr -1 from c . 510 Ma to c . 500 Ma. Whereas, 40 Ar/ 39 Ar data obtained from plagioclase and K–feldspar suggest a slower cooling from c . 500 Ma to c . 460 Ma with cooling rates from 5 to 2°C myr -1 . These results demonstrate that the early Palaeozoic cooling history and comparable palaeostress regimes are regionally extensive, which has important implications for the tectonothermal and stress-field variability across Gondwana. The elevated thermal conditions would induce lithospheric weakening and promote the early Palaeozoic intraplate orogeny observed in eastern Antarctica with the development of a large intracratonic shear system. |
format |
Article in Journal/Newspaper |
author |
Wilson, Christopher J.L. Quinn, Cameron Tong, Laixi Phillips, David |
spellingShingle |
Wilson, Christopher J.L. Quinn, Cameron Tong, Laixi Phillips, David Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
author_facet |
Wilson, Christopher J.L. Quinn, Cameron Tong, Laixi Phillips, David |
author_sort |
Wilson, Christopher J.L. |
title |
Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
title_short |
Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
title_full |
Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
title_fullStr |
Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
title_full_unstemmed |
Early Palaeozoic intracratonic shears and post-tectonic cooling in the Rauer Group, Prydz Bay, East Antarctica constrained by 40 Ar/ 39 Ar thermochronology |
title_sort |
early palaeozoic intracratonic shears and post-tectonic cooling in the rauer group, prydz bay, east antarctica constrained by 40 ar/ 39 ar thermochronology |
publisher |
Cambridge University Press (CUP) |
publishDate |
2007 |
url |
http://dx.doi.org/10.1017/s0954102007000478 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102007000478 |
genre |
Antarc* Antarctic Science Antarctica East Antarctica Prince Charles Mountains Prydz Bay |
genre_facet |
Antarc* Antarctic Science Antarctica East Antarctica Prince Charles Mountains Prydz Bay |
op_source |
Antarctic Science volume 19, issue 3, page 339-353 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0954102007000478 |
container_title |
Antarctic Science |
container_volume |
19 |
container_issue |
3 |
container_start_page |
339 |
op_container_end_page |
353 |
_version_ |
1810487768907776000 |