On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica
We present electron microprobe-based in situ (Th + U)-Pb monazite chemical age data from granulite-facies metapelites in Prydz Bay, East Antarctica. The monazite age data define two distinct age populations, Late Neoproterozoic to Early Palaeozoic (c. 570-520 Ma) and Neoproterozoic (c. 950-820 Ma),...
Published in: | Journal of the Geological Society |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Geological Soc Publ House
2007
|
Subjects: | |
Online Access: | http://hdl.handle.net/2440/43723 https://doi.org/10.1144/0016-76492006-013 |
id |
ftunivadelaidedl:oai:digital.library.adelaide.edu.au:2440/43723 |
---|---|
record_format |
openpolar |
spelling |
ftunivadelaidedl:oai:digital.library.adelaide.edu.au:2440/43723 2023-05-15T13:45:29+02:00 On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica On the application of in situ monazite chemical geochronology to constraining P-T-t histories in high-temperature (> 850 degrees C polymetamorphic granulites from Prydz Bay, East Antarctica Kelsey, D. Hand, M. Clark, C. Wilson, C. 2007 http://hdl.handle.net/2440/43723 https://doi.org/10.1144/0016-76492006-013 en eng Geological Soc Publ House Journal of the Geological Society, 2007; 164(3):667-683 0016-7649 2041-479X http://hdl.handle.net/2440/43723 doi:10.1144/0016-76492006-013 Hand, M. [0000-0003-3743-9706] © 2007 Geological Society of London http://jgs.lyellcollection.org/cgi/content/abstract/164/3/667 Journal article 2007 ftunivadelaidedl https://doi.org/10.1144/0016-76492006-013 2023-02-05T19:11:38Z We present electron microprobe-based in situ (Th + U)-Pb monazite chemical age data from granulite-facies metapelites in Prydz Bay, East Antarctica. The monazite age data define two distinct age populations, Late Neoproterozoic to Early Palaeozoic (c. 570-520 Ma) and Neoproterozoic (c. 950-820 Ma), that confirm the polytectonic nature of Prydz Bay. Our data suggest that similarity in lineation orientation along the Prydz Bay coast is not sufficient to necessarily indicate time-equivalance. The minimum duration of Early Palaeozoic tectonism, spanning at least 60 Ma, is constrained from an Mg-Al-rich metapelite: monazite hosted by coarse-grained orthopyroxene defines the oldest Early Palaeozoic population, whereas cordierite + orthopyroxene symplectites define the youngest Early Palaeozoic population. The spatial distribution of monazites and their ages is correlatable with the inferred mineral assemblage evolution. We are able to characterize the evolution of Early Palaeozoic tectonism in quantitative P-T-t-mineral assemblage space, demonstrating that ultrahigh-temperature tectono-metamorphism in Prydz Bay is of Early Palaeozoic age. The survival of Neoproterozoic inheritance in Fe-Al-rich metapelites has implications for high Pb retentivity in monazite when chemical and kinetic conditions are favourable. The approach and logic applied herein are entirely and directly transferable to the interrogation of any other metamorphic terrane. D.E. Kelsey, M. Hand, C. Clark & C.J.L. Wilson Article in Journal/Newspaper Antarc* Antarctica East Antarctica Prydz Bay The University of Adelaide: Digital Library East Antarctica Kelsey ENVELOPE(-22.306,-22.306,-80.448,-80.448) Prydz Bay Journal of the Geological Society 164 3 667 683 |
institution |
Open Polar |
collection |
The University of Adelaide: Digital Library |
op_collection_id |
ftunivadelaidedl |
language |
English |
description |
We present electron microprobe-based in situ (Th + U)-Pb monazite chemical age data from granulite-facies metapelites in Prydz Bay, East Antarctica. The monazite age data define two distinct age populations, Late Neoproterozoic to Early Palaeozoic (c. 570-520 Ma) and Neoproterozoic (c. 950-820 Ma), that confirm the polytectonic nature of Prydz Bay. Our data suggest that similarity in lineation orientation along the Prydz Bay coast is not sufficient to necessarily indicate time-equivalance. The minimum duration of Early Palaeozoic tectonism, spanning at least 60 Ma, is constrained from an Mg-Al-rich metapelite: monazite hosted by coarse-grained orthopyroxene defines the oldest Early Palaeozoic population, whereas cordierite + orthopyroxene symplectites define the youngest Early Palaeozoic population. The spatial distribution of monazites and their ages is correlatable with the inferred mineral assemblage evolution. We are able to characterize the evolution of Early Palaeozoic tectonism in quantitative P-T-t-mineral assemblage space, demonstrating that ultrahigh-temperature tectono-metamorphism in Prydz Bay is of Early Palaeozoic age. The survival of Neoproterozoic inheritance in Fe-Al-rich metapelites has implications for high Pb retentivity in monazite when chemical and kinetic conditions are favourable. The approach and logic applied herein are entirely and directly transferable to the interrogation of any other metamorphic terrane. D.E. Kelsey, M. Hand, C. Clark & C.J.L. Wilson |
format |
Article in Journal/Newspaper |
author |
Kelsey, D. Hand, M. Clark, C. Wilson, C. |
spellingShingle |
Kelsey, D. Hand, M. Clark, C. Wilson, C. On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
author_facet |
Kelsey, D. Hand, M. Clark, C. Wilson, C. |
author_sort |
Kelsey, D. |
title |
On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
title_short |
On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
title_full |
On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
title_fullStr |
On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
title_full_unstemmed |
On the application of in situ monazite chemical geochronology to constraining P–T–t histories in high-temperature (>850 °C) polymetamorphic granulites from Prydz Bay, East Antarctica |
title_sort |
on the application of in situ monazite chemical geochronology to constraining p–t–t histories in high-temperature (>850 °c) polymetamorphic granulites from prydz bay, east antarctica |
publisher |
Geological Soc Publ House |
publishDate |
2007 |
url |
http://hdl.handle.net/2440/43723 https://doi.org/10.1144/0016-76492006-013 |
long_lat |
ENVELOPE(-22.306,-22.306,-80.448,-80.448) |
geographic |
East Antarctica Kelsey Prydz Bay |
geographic_facet |
East Antarctica Kelsey Prydz Bay |
genre |
Antarc* Antarctica East Antarctica Prydz Bay |
genre_facet |
Antarc* Antarctica East Antarctica Prydz Bay |
op_source |
http://jgs.lyellcollection.org/cgi/content/abstract/164/3/667 |
op_relation |
Journal of the Geological Society, 2007; 164(3):667-683 0016-7649 2041-479X http://hdl.handle.net/2440/43723 doi:10.1144/0016-76492006-013 Hand, M. [0000-0003-3743-9706] |
op_rights |
© 2007 Geological Society of London |
op_doi |
https://doi.org/10.1144/0016-76492006-013 |
container_title |
Journal of the Geological Society |
container_volume |
164 |
container_issue |
3 |
container_start_page |
667 |
op_container_end_page |
683 |
_version_ |
1766225014477029376 |