Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology

In East Antarctica’s Archaean-Proterozoic Rayner Complex, metasedimentary gneisses at Stillwell Hills in Kemp Land are interfolded with orthogneisses. At Cape Bruce and Forbes Glacier in MacRobertson Land, metasediments form more continuous exposures that are intruded by the Mawson Charnockite (c.98...

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Main Author: K. R. Murray
Format: Thesis
Language:unknown
Published: 2018
Subjects:
Online Access:https://doi.org/10.25949/19439288.v1
https://figshare.com/articles/thesis/Comparison_of_detrital_and_metamorphic_zircon_from_metapelites_in_the_Rayner_Complex_east_Antarctica_provenance_and_age_of_deposition_investigated_via_U-Pb_and_Hf-analysis_and_interpretation_of_Th_U_ratio_CL_zonation_and_morphology/19439288
id ftmacquariefig:oai:figshare.com:article/19439288
record_format openpolar
spelling ftmacquariefig:oai:figshare.com:article/19439288 2023-05-15T13:41:11+02:00 Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology K. R. Murray 2018-06-28T00:00:00Z https://doi.org/10.25949/19439288.v1 https://figshare.com/articles/thesis/Comparison_of_detrital_and_metamorphic_zircon_from_metapelites_in_the_Rayner_Complex_east_Antarctica_provenance_and_age_of_deposition_investigated_via_U-Pb_and_Hf-analysis_and_interpretation_of_Th_U_ratio_CL_zonation_and_morphology/19439288 unknown doi:10.25949/19439288.v1 https://figshare.com/articles/thesis/Comparison_of_detrital_and_metamorphic_zircon_from_metapelites_in_the_Rayner_Complex_east_Antarctica_provenance_and_age_of_deposition_investigated_via_U-Pb_and_Hf-analysis_and_interpretation_of_Th_U_ratio_CL_zonation_and_morphology/19439288 In Copyright Other education not elsewhere classified Zircon -- Analysis Geological time Gneiss -- Analysis Zircon Geology Geology -- Antarctica Gneiss Text Thesis 2018 ftmacquariefig https://doi.org/10.25949/19439288.v1 2022-12-28T08:38:13Z In East Antarctica’s Archaean-Proterozoic Rayner Complex, metasedimentary gneisses at Stillwell Hills in Kemp Land are interfolded with orthogneisses. At Cape Bruce and Forbes Glacier in MacRobertson Land, metasediments form more continuous exposures that are intruded by the Mawson Charnockite (c.980Ma) (Halpin et al 2005; Young & Black 1991). Detrital and metamorphic zircon grains from six metapelitic samples were analysed for U-Pb age, TDMͨ, εHf, Th-U ratio, length, CL zoning and morphology. This detailed analysis helped to determine their age of deposition as sediments, when they were metamorphosed and the provenance of the grains within each sample. Colbeck Gneiss from Cape Bruce (AC34) recorded a 207/206Pb maximum depositional age of 1258±23 Ma. A metapelitic lens within Painted Gneiss in Forbes Glacier (90024) recorded a maximum depositional age of 1251±27 Ma. These dates correlate with Young and Black (1991) whole rock analysis of these two Proterozoic gneisses. To better understand the regional history of Stillwell Hills, four metapelites were dated to determine their relative age compared with host Stillwell orthogneiss. This work indicates that even the oldest inherited zircons in these four metapelite samples are a minimum 340Ma younger than the youngest dated zircon from Archaean Stillwell orthogneiss (Halpin et al 2005). In order of deposition, Pink Gneiss (FS0214) maximum depositional age is 1317±51 Ma; followed by Green layered sequence (GS01) at 1316±33 Ma, Garnet-sillimanite metapelite (SW54) at 1260±47 Ma and Rusty gneiss (FS0223) the youngest at1178±84 Ma. Petrogenesis of the majority of zircon grains in all six samples could be traced to felsicigneous events. Considering Antarctic basement rock is formed from igneous mafic granitoids (Veevers &Saeed 2011), this felsic trend indicates that most detritus originated not from Archaean basement protoliths, but younger, more crustally evolved, sources. All samples, to a greater or lesser extent,contained zircon grains whose U-Pb age, TDMͨ, ... Thesis Antarc* Antarctic Antarctica East Antarctica Kemp Land MacRobertson Land Research from Macquarie University Antarctic East Antarctica Forbes ENVELOPE(-66.550,-66.550,-67.783,-67.783) Rayner ENVELOPE(-45.166,-45.166,-60.650,-60.650) Kemp Land ENVELOPE(57.500,57.500,-67.500,-67.500) MacRobertson Land ENVELOPE(65.000,65.000,-70.000,-70.000) Colbeck ENVELOPE(-158.017,-158.017,-77.117,-77.117) Stillwell Hills ENVELOPE(59.467,59.467,-67.417,-67.417) Forbes Glacier ENVELOPE(62.350,62.350,-67.633,-67.633) Cape Bruce ENVELOPE(60.795,60.795,-67.427,-67.427)
institution Open Polar
collection Research from Macquarie University
op_collection_id ftmacquariefig
language unknown
topic Other education not elsewhere classified
Zircon -- Analysis
Geological time
Gneiss -- Analysis
Zircon
Geology
Geology -- Antarctica
Gneiss
spellingShingle Other education not elsewhere classified
Zircon -- Analysis
Geological time
Gneiss -- Analysis
Zircon
Geology
Geology -- Antarctica
Gneiss
K. R. Murray
Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
topic_facet Other education not elsewhere classified
Zircon -- Analysis
Geological time
Gneiss -- Analysis
Zircon
Geology
Geology -- Antarctica
Gneiss
description In East Antarctica’s Archaean-Proterozoic Rayner Complex, metasedimentary gneisses at Stillwell Hills in Kemp Land are interfolded with orthogneisses. At Cape Bruce and Forbes Glacier in MacRobertson Land, metasediments form more continuous exposures that are intruded by the Mawson Charnockite (c.980Ma) (Halpin et al 2005; Young & Black 1991). Detrital and metamorphic zircon grains from six metapelitic samples were analysed for U-Pb age, TDMͨ, εHf, Th-U ratio, length, CL zoning and morphology. This detailed analysis helped to determine their age of deposition as sediments, when they were metamorphosed and the provenance of the grains within each sample. Colbeck Gneiss from Cape Bruce (AC34) recorded a 207/206Pb maximum depositional age of 1258±23 Ma. A metapelitic lens within Painted Gneiss in Forbes Glacier (90024) recorded a maximum depositional age of 1251±27 Ma. These dates correlate with Young and Black (1991) whole rock analysis of these two Proterozoic gneisses. To better understand the regional history of Stillwell Hills, four metapelites were dated to determine their relative age compared with host Stillwell orthogneiss. This work indicates that even the oldest inherited zircons in these four metapelite samples are a minimum 340Ma younger than the youngest dated zircon from Archaean Stillwell orthogneiss (Halpin et al 2005). In order of deposition, Pink Gneiss (FS0214) maximum depositional age is 1317±51 Ma; followed by Green layered sequence (GS01) at 1316±33 Ma, Garnet-sillimanite metapelite (SW54) at 1260±47 Ma and Rusty gneiss (FS0223) the youngest at1178±84 Ma. Petrogenesis of the majority of zircon grains in all six samples could be traced to felsicigneous events. Considering Antarctic basement rock is formed from igneous mafic granitoids (Veevers &Saeed 2011), this felsic trend indicates that most detritus originated not from Archaean basement protoliths, but younger, more crustally evolved, sources. All samples, to a greater or lesser extent,contained zircon grains whose U-Pb age, TDMͨ, ...
format Thesis
author K. R. Murray
author_facet K. R. Murray
author_sort K. R. Murray
title Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
title_short Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
title_full Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
title_fullStr Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
title_full_unstemmed Comparison of detrital and metamorphic zircon from metapelites in the Rayner Complex, east Antarctica: provenance and age of deposition investigated via U-Pb and Hf-analysis and interpretation of Th/U ratio, CL zonation and morphology
title_sort comparison of detrital and metamorphic zircon from metapelites in the rayner complex, east antarctica: provenance and age of deposition investigated via u-pb and hf-analysis and interpretation of th/u ratio, cl zonation and morphology
publishDate 2018
url https://doi.org/10.25949/19439288.v1
https://figshare.com/articles/thesis/Comparison_of_detrital_and_metamorphic_zircon_from_metapelites_in_the_Rayner_Complex_east_Antarctica_provenance_and_age_of_deposition_investigated_via_U-Pb_and_Hf-analysis_and_interpretation_of_Th_U_ratio_CL_zonation_and_morphology/19439288
long_lat ENVELOPE(-66.550,-66.550,-67.783,-67.783)
ENVELOPE(-45.166,-45.166,-60.650,-60.650)
ENVELOPE(57.500,57.500,-67.500,-67.500)
ENVELOPE(65.000,65.000,-70.000,-70.000)
ENVELOPE(-158.017,-158.017,-77.117,-77.117)
ENVELOPE(59.467,59.467,-67.417,-67.417)
ENVELOPE(62.350,62.350,-67.633,-67.633)
ENVELOPE(60.795,60.795,-67.427,-67.427)
geographic Antarctic
East Antarctica
Forbes
Rayner
Kemp Land
MacRobertson Land
Colbeck
Stillwell Hills
Forbes Glacier
Cape Bruce
geographic_facet Antarctic
East Antarctica
Forbes
Rayner
Kemp Land
MacRobertson Land
Colbeck
Stillwell Hills
Forbes Glacier
Cape Bruce
genre Antarc*
Antarctic
Antarctica
East Antarctica
Kemp Land
MacRobertson Land
genre_facet Antarc*
Antarctic
Antarctica
East Antarctica
Kemp Land
MacRobertson Land
op_relation doi:10.25949/19439288.v1
https://figshare.com/articles/thesis/Comparison_of_detrital_and_metamorphic_zircon_from_metapelites_in_the_Rayner_Complex_east_Antarctica_provenance_and_age_of_deposition_investigated_via_U-Pb_and_Hf-analysis_and_interpretation_of_Th_U_ratio_CL_zonation_and_morphology/19439288
op_rights In Copyright
op_doi https://doi.org/10.25949/19439288.v1
_version_ 1766146536302968832