Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle
The Grove Mountains of East Antarctica are an inland continuation of the Prydz Belt. The high-grade metamorphic complex in this area is composed of felsic orthogneisses and mafic granulites, with minor paragneisses and calc-silicate rocks. U-Pb zircon analyses using SHRIMP and LA-ICP-MS techniques r...
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Elsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/precamres
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Online Access: | https://doi.org/10.1016/j.precamres.2007.04.005 http://hdl.handle.net/10722/151213 |
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ftunivhongkonghu:oai:hub.hku.hk:10722/151213 2023-05-15T13:46:34+02:00 Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle Jahn, BM Zhao, G Zhao, Y Liu, X 2007 https://doi.org/10.1016/j.precamres.2007.04.005 http://hdl.handle.net/10722/151213 eng eng Elsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/precamres Netherlands Precambrian Research http://www.scopus.com/mlt/select.url?eid=2-s2.0-34547800112&selection=ref&src=s&origin=recordpage Precambrian Research, 2007, v. 158 n. 1-2, p. 93-118 doi:10.1016/j.precamres.2007.04.005 118 144323 WOS:000249482900005 0301-9268 1-2 eid_2-s2.0-34547800112 93 http://hdl.handle.net/10722/151213 158 Precambrian Research. Copyright © Elsevier BV. Grove Mountains Single Metamorphic Cycle Prydz Belt Mafic-Felsic Intrusion Early Neoproterozoic East Antarctica Late Neoproterozoic/Cambrian Article 2007 ftunivhongkonghu https://doi.org/10.1016/j.precamres.2007.04.005 2023-01-14T15:43:31Z The Grove Mountains of East Antarctica are an inland continuation of the Prydz Belt. The high-grade metamorphic complex in this area is composed of felsic orthogneisses and mafic granulites, with minor paragneisses and calc-silicate rocks. U-Pb zircon analyses using SHRIMP and LA-ICP-MS techniques reveal that the protoliths of mafic granulites and felsic orthogneisses were emplaced during a short time interval of ca. 920-910 Ma. Mafic granulites can be divided into low- and high-Ti groups. They have initial εNd values [εNd(T)] ranging from +0.8 to -1.9. TiO2 is positively correlated with FeOt/MgO and La/Nb ratios, whereas it shows a negative correlation with εNd(T) values, indicating that the petrogenesis of their protoliths involved partial melting of a weakly enriched subcontinental lithospheric mantle and fractional crystallization of the magma accompanied by minor crustal contamination. Felsic orthogneisses have an affinity of A2-type granites, characterized by enrichment in REE, Y, Zr, Th and Ga and high Ga/Al and Y/Nb ratios. Most of them have εNd(T) values of -0.7 to -3.5 and Nd depleted mantle model ages (TDM) of 1.76-1.65 Ga, and a few have low εNd(T) values of -10.4 to -10.6 and old TDM of 2.46-2.27 Ga, reflecting a heterogeneity in their source region. Their protoliths were probably produced by high-temperature partial melting of tonalitic-granodioritic rocks triggered by the underplating of mantle-derived mafic magma during post-orogenic extension. U-Pb analyses also reveal a metamorphic age of ca. 2050 Ma from detrital zircons in a paragneiss, suggesting that the sedimentary materials of the paragneiss may have come from an as yet undiscovered Early Paleoproterozoic orogen of unknown provenance. Voluminous mafic-felsic intrusives and a small amount of sedimentary rocks constitute an Early Neoproterozoic basement of the Grove Mountains. Subsequently, this basement experienced only a single Late Neoproterozoic/Cambrian metamorphic cycle at ca. 550-535 Ma. The available data indicate that the Prydz ... Article in Journal/Newspaper Antarc* Antarctica East Antarctica University of Hong Kong: HKU Scholars Hub East Antarctica Grove Mountains ENVELOPE(75.000,75.000,-72.750,-72.750) Precambrian Research 158 1-2 93 118 |
institution |
Open Polar |
collection |
University of Hong Kong: HKU Scholars Hub |
op_collection_id |
ftunivhongkonghu |
language |
English |
topic |
Grove Mountains Single Metamorphic Cycle Prydz Belt Mafic-Felsic Intrusion Early Neoproterozoic East Antarctica Late Neoproterozoic/Cambrian |
spellingShingle |
Grove Mountains Single Metamorphic Cycle Prydz Belt Mafic-Felsic Intrusion Early Neoproterozoic East Antarctica Late Neoproterozoic/Cambrian Jahn, BM Zhao, G Zhao, Y Liu, X Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
topic_facet |
Grove Mountains Single Metamorphic Cycle Prydz Belt Mafic-Felsic Intrusion Early Neoproterozoic East Antarctica Late Neoproterozoic/Cambrian |
description |
The Grove Mountains of East Antarctica are an inland continuation of the Prydz Belt. The high-grade metamorphic complex in this area is composed of felsic orthogneisses and mafic granulites, with minor paragneisses and calc-silicate rocks. U-Pb zircon analyses using SHRIMP and LA-ICP-MS techniques reveal that the protoliths of mafic granulites and felsic orthogneisses were emplaced during a short time interval of ca. 920-910 Ma. Mafic granulites can be divided into low- and high-Ti groups. They have initial εNd values [εNd(T)] ranging from +0.8 to -1.9. TiO2 is positively correlated with FeOt/MgO and La/Nb ratios, whereas it shows a negative correlation with εNd(T) values, indicating that the petrogenesis of their protoliths involved partial melting of a weakly enriched subcontinental lithospheric mantle and fractional crystallization of the magma accompanied by minor crustal contamination. Felsic orthogneisses have an affinity of A2-type granites, characterized by enrichment in REE, Y, Zr, Th and Ga and high Ga/Al and Y/Nb ratios. Most of them have εNd(T) values of -0.7 to -3.5 and Nd depleted mantle model ages (TDM) of 1.76-1.65 Ga, and a few have low εNd(T) values of -10.4 to -10.6 and old TDM of 2.46-2.27 Ga, reflecting a heterogeneity in their source region. Their protoliths were probably produced by high-temperature partial melting of tonalitic-granodioritic rocks triggered by the underplating of mantle-derived mafic magma during post-orogenic extension. U-Pb analyses also reveal a metamorphic age of ca. 2050 Ma from detrital zircons in a paragneiss, suggesting that the sedimentary materials of the paragneiss may have come from an as yet undiscovered Early Paleoproterozoic orogen of unknown provenance. Voluminous mafic-felsic intrusives and a small amount of sedimentary rocks constitute an Early Neoproterozoic basement of the Grove Mountains. Subsequently, this basement experienced only a single Late Neoproterozoic/Cambrian metamorphic cycle at ca. 550-535 Ma. The available data indicate that the Prydz ... |
format |
Article in Journal/Newspaper |
author |
Jahn, BM Zhao, G Zhao, Y Liu, X |
author_facet |
Jahn, BM Zhao, G Zhao, Y Liu, X |
author_sort |
Jahn, BM |
title |
Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
title_short |
Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
title_full |
Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
title_fullStr |
Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
title_full_unstemmed |
Geochemistry and geochronology of high-grade rocks from the Grove Mountains, East Antarctica: Evidence for an Early Neoproterozoic basement metamorphosed during a single Late Neoproterozoic/Cambrian tectonic cycle |
title_sort |
geochemistry and geochronology of high-grade rocks from the grove mountains, east antarctica: evidence for an early neoproterozoic basement metamorphosed during a single late neoproterozoic/cambrian tectonic cycle |
publisher |
Elsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/precamres |
publishDate |
2007 |
url |
https://doi.org/10.1016/j.precamres.2007.04.005 http://hdl.handle.net/10722/151213 |
long_lat |
ENVELOPE(75.000,75.000,-72.750,-72.750) |
geographic |
East Antarctica Grove Mountains |
geographic_facet |
East Antarctica Grove Mountains |
genre |
Antarc* Antarctica East Antarctica |
genre_facet |
Antarc* Antarctica East Antarctica |
op_relation |
Precambrian Research http://www.scopus.com/mlt/select.url?eid=2-s2.0-34547800112&selection=ref&src=s&origin=recordpage Precambrian Research, 2007, v. 158 n. 1-2, p. 93-118 doi:10.1016/j.precamres.2007.04.005 118 144323 WOS:000249482900005 0301-9268 1-2 eid_2-s2.0-34547800112 93 http://hdl.handle.net/10722/151213 158 |
op_rights |
Precambrian Research. Copyright © Elsevier BV. |
op_doi |
https://doi.org/10.1016/j.precamres.2007.04.005 |
container_title |
Precambrian Research |
container_volume |
158 |
container_issue |
1-2 |
container_start_page |
93 |
op_container_end_page |
118 |
_version_ |
1766244226395275264 |