The continental record and the generation of continental crust
Continental crust is the archive of Earth history. The spatial and temporal distribution of Earth's record of rock units and events is heterogeneous; for example, ages of igneous crystallization, metamorphism, continental margins, mineralization, and seawater and atmospheric proxies are distrib...
Published in: | Geological Society of America Bulletin |
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Online Access: | https://hdl.handle.net/1983/9cf946e9-08a6-446a-b130-f74d50cca63e https://research-information.bris.ac.uk/en/publications/9cf946e9-08a6-446a-b130-f74d50cca63e https://doi.org/10.1130/B30722.1 |
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ftubristolcris:oai:research-information.bris.ac.uk:publications/9cf946e9-08a6-446a-b130-f74d50cca63e 2024-05-19T07:41:29+00:00 The continental record and the generation of continental crust Cawood, P. A. Hawkesworth, C. J. Dhuime, B. 2013 https://hdl.handle.net/1983/9cf946e9-08a6-446a-b130-f74d50cca63e https://research-information.bris.ac.uk/en/publications/9cf946e9-08a6-446a-b130-f74d50cca63e https://doi.org/10.1130/B30722.1 eng eng https://research-information.bris.ac.uk/en/publications/9cf946e9-08a6-446a-b130-f74d50cca63e info:eu-repo/semantics/restrictedAccess Cawood , P A , Hawkesworth , C J & Dhuime , B 2013 , ' The continental record and the generation of continental crust ' , Geological Society of America Bulletin , vol. 125 , no. 1-2 , pp. 14-32 . https://doi.org/10.1130/B30722.1 DIFFERENTIAL ZIRCON FERTILITY SOUTHERN WEST GREENLAND HF-ISOTOPE EVIDENCE DETRITAL ZIRCONS U-PB PLATE-TECTONICS LITHOSPHERIC MANTLE SUBDUCTION ZONES EARTHS CRUST HEAT-FLOW article 2013 ftubristolcris https://doi.org/10.1130/B30722.1 2024-04-23T23:46:57Z Continental crust is the archive of Earth history. The spatial and temporal distribution of Earth's record of rock units and events is heterogeneous; for example, ages of igneous crystallization, metamorphism, continental margins, mineralization, and seawater and atmospheric proxies are distributed about a series of peaks and troughs. This distribution reflects the different preservation potential of rocks generated in different tectonic settings, rather than fundamental pulses of activity, and the peaks of ages are linked to the timing of supercontinent assembly. The physio-chemical resilience of zircons and their derivation largely from felsic igneous rocks means that they are important indicators of the crustal record. Furthermore, detrital zircons, which sample a range of source rocks, provide a more representative record than direct analysis of grains in igneous rocks. Analysis of detrital zircons suggests that at least similar to 60%-70% of the present volume of the continental crust had been generated by 3 Ga. Such estimates seek to take account of the extent to which the old crustal material is underrepresented in the sedimentary record, and they imply that there were greater volumes of continental crust in the Archean than might be inferred from the compositions of detrital zircons and sediments. The growth of continental crust was a continuous rather than an episodic process, but there was a marked decrease in the rate of crustal growth at ca. 3 Ga, which may have been linked to the onset of significant crustal recycling, probably through subduction at convergent plate margins. The Hadean and Early Archean continental record is poorly preserved and characterized by a bimodal TTG (tonalites, trondhjemites, and granodiorites) and greenstone association that differs from the younger record that can be more directly related to a plate-tectonic regime. The paucity of this early record has led to competing and equivocal models invoking plate-tectonic- and mantle-plume-dominated processes. The 60%-70% of the ... Article in Journal/Newspaper Greenland University of Bristol: Bristol Research Geological Society of America Bulletin 125 1-2 14 32 |
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Open Polar |
collection |
University of Bristol: Bristol Research |
op_collection_id |
ftubristolcris |
language |
English |
topic |
DIFFERENTIAL ZIRCON FERTILITY SOUTHERN WEST GREENLAND HF-ISOTOPE EVIDENCE DETRITAL ZIRCONS U-PB PLATE-TECTONICS LITHOSPHERIC MANTLE SUBDUCTION ZONES EARTHS CRUST HEAT-FLOW |
spellingShingle |
DIFFERENTIAL ZIRCON FERTILITY SOUTHERN WEST GREENLAND HF-ISOTOPE EVIDENCE DETRITAL ZIRCONS U-PB PLATE-TECTONICS LITHOSPHERIC MANTLE SUBDUCTION ZONES EARTHS CRUST HEAT-FLOW Cawood, P. A. Hawkesworth, C. J. Dhuime, B. The continental record and the generation of continental crust |
topic_facet |
DIFFERENTIAL ZIRCON FERTILITY SOUTHERN WEST GREENLAND HF-ISOTOPE EVIDENCE DETRITAL ZIRCONS U-PB PLATE-TECTONICS LITHOSPHERIC MANTLE SUBDUCTION ZONES EARTHS CRUST HEAT-FLOW |
description |
Continental crust is the archive of Earth history. The spatial and temporal distribution of Earth's record of rock units and events is heterogeneous; for example, ages of igneous crystallization, metamorphism, continental margins, mineralization, and seawater and atmospheric proxies are distributed about a series of peaks and troughs. This distribution reflects the different preservation potential of rocks generated in different tectonic settings, rather than fundamental pulses of activity, and the peaks of ages are linked to the timing of supercontinent assembly. The physio-chemical resilience of zircons and their derivation largely from felsic igneous rocks means that they are important indicators of the crustal record. Furthermore, detrital zircons, which sample a range of source rocks, provide a more representative record than direct analysis of grains in igneous rocks. Analysis of detrital zircons suggests that at least similar to 60%-70% of the present volume of the continental crust had been generated by 3 Ga. Such estimates seek to take account of the extent to which the old crustal material is underrepresented in the sedimentary record, and they imply that there were greater volumes of continental crust in the Archean than might be inferred from the compositions of detrital zircons and sediments. The growth of continental crust was a continuous rather than an episodic process, but there was a marked decrease in the rate of crustal growth at ca. 3 Ga, which may have been linked to the onset of significant crustal recycling, probably through subduction at convergent plate margins. The Hadean and Early Archean continental record is poorly preserved and characterized by a bimodal TTG (tonalites, trondhjemites, and granodiorites) and greenstone association that differs from the younger record that can be more directly related to a plate-tectonic regime. The paucity of this early record has led to competing and equivocal models invoking plate-tectonic- and mantle-plume-dominated processes. The 60%-70% of the ... |
format |
Article in Journal/Newspaper |
author |
Cawood, P. A. Hawkesworth, C. J. Dhuime, B. |
author_facet |
Cawood, P. A. Hawkesworth, C. J. Dhuime, B. |
author_sort |
Cawood, P. A. |
title |
The continental record and the generation of continental crust |
title_short |
The continental record and the generation of continental crust |
title_full |
The continental record and the generation of continental crust |
title_fullStr |
The continental record and the generation of continental crust |
title_full_unstemmed |
The continental record and the generation of continental crust |
title_sort |
continental record and the generation of continental crust |
publishDate |
2013 |
url |
https://hdl.handle.net/1983/9cf946e9-08a6-446a-b130-f74d50cca63e https://research-information.bris.ac.uk/en/publications/9cf946e9-08a6-446a-b130-f74d50cca63e https://doi.org/10.1130/B30722.1 |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
Cawood , P A , Hawkesworth , C J & Dhuime , B 2013 , ' The continental record and the generation of continental crust ' , Geological Society of America Bulletin , vol. 125 , no. 1-2 , pp. 14-32 . https://doi.org/10.1130/B30722.1 |
op_relation |
https://research-information.bris.ac.uk/en/publications/9cf946e9-08a6-446a-b130-f74d50cca63e |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1130/B30722.1 |
container_title |
Geological Society of America Bulletin |
container_volume |
125 |
container_issue |
1-2 |
container_start_page |
14 |
op_container_end_page |
32 |
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1799481081272991744 |