Antiquity of the Oceans and Continents
Tracing the origin of the oceans and the division of the crust into distinct oceanic and continental realms relies on incomplete information from tiny vestiges of surviving oldest crust (>3.6 billions years old). Billions of years of tectonism, melting and erosion have obliterated the rest of tha...
Published in: | Elements |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Mineralogical Society of America
|
Subjects: | |
Online Access: | http://hdl.handle.net/1885/20352 https://doi.org/10.2113/gselements.2.4.223 |
id |
ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/20352 |
---|---|
record_format |
openpolar |
spelling |
ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/20352 2024-01-14T10:04:43+01:00 Antiquity of the Oceans and Continents Nutman, Allen http://hdl.handle.net/1885/20352 https://doi.org/10.2113/gselements.2.4.223 unknown Mineralogical Society of America 1811-5209 http://hdl.handle.net/1885/20352 doi:10.2113/gselements.2.4.223 Elements Keywords: continental crust early Earth gneiss oceanic crust orogeny plate boundary tectonic evolution zircon Akilia Arctic Australasia Australia Greenland Isua Greenstone Belt Jack Hills Western Australia Acasta Acasta Continents Isua Oceans Zircons Journal article ftanucanberra https://doi.org/10.2113/gselements.2.4.223 2023-12-15T09:33:05Z Tracing the origin of the oceans and the division of the crust into distinct oceanic and continental realms relies on incomplete information from tiny vestiges of surviving oldest crust (>3.6 billions years old). Billions of years of tectonism, melting and erosion have obliterated the rest of that crust. Oceans and continental crust already existed almost four billion years ago because water-laid sedimentary rocks of this age have been found and because tonalites dominate in gneissic sequences dating from this period. Tonalites are igneous rocks produced by partial melting of hydrated basaltic crust at convergent plate boundaries. Collisional orogenic systems produced granites by partial melting of tonalite crust 3.7-3.6 billion years ago. Thus the oldest rocks can be understood in terms of a plate tectonic regime. The chemistry of even older detrital zircons may argue for continental crust and oceans back to 4.4 and 4.2 billion years ago, respectively. Maybe only within the first 200 million years was Earth's surface hot, dry and predominantly shaped by impacts. Article in Journal/Newspaper Arctic Greenland Australian National University: ANU Digital Collections Arctic Greenland Elements 2 4 223 227 |
institution |
Open Polar |
collection |
Australian National University: ANU Digital Collections |
op_collection_id |
ftanucanberra |
language |
unknown |
topic |
Keywords: continental crust early Earth gneiss oceanic crust orogeny plate boundary tectonic evolution zircon Akilia Arctic Australasia Australia Greenland Isua Greenstone Belt Jack Hills Western Australia Acasta Acasta Continents Isua Oceans Zircons |
spellingShingle |
Keywords: continental crust early Earth gneiss oceanic crust orogeny plate boundary tectonic evolution zircon Akilia Arctic Australasia Australia Greenland Isua Greenstone Belt Jack Hills Western Australia Acasta Acasta Continents Isua Oceans Zircons Nutman, Allen Antiquity of the Oceans and Continents |
topic_facet |
Keywords: continental crust early Earth gneiss oceanic crust orogeny plate boundary tectonic evolution zircon Akilia Arctic Australasia Australia Greenland Isua Greenstone Belt Jack Hills Western Australia Acasta Acasta Continents Isua Oceans Zircons |
description |
Tracing the origin of the oceans and the division of the crust into distinct oceanic and continental realms relies on incomplete information from tiny vestiges of surviving oldest crust (>3.6 billions years old). Billions of years of tectonism, melting and erosion have obliterated the rest of that crust. Oceans and continental crust already existed almost four billion years ago because water-laid sedimentary rocks of this age have been found and because tonalites dominate in gneissic sequences dating from this period. Tonalites are igneous rocks produced by partial melting of hydrated basaltic crust at convergent plate boundaries. Collisional orogenic systems produced granites by partial melting of tonalite crust 3.7-3.6 billion years ago. Thus the oldest rocks can be understood in terms of a plate tectonic regime. The chemistry of even older detrital zircons may argue for continental crust and oceans back to 4.4 and 4.2 billion years ago, respectively. Maybe only within the first 200 million years was Earth's surface hot, dry and predominantly shaped by impacts. |
format |
Article in Journal/Newspaper |
author |
Nutman, Allen |
author_facet |
Nutman, Allen |
author_sort |
Nutman, Allen |
title |
Antiquity of the Oceans and Continents |
title_short |
Antiquity of the Oceans and Continents |
title_full |
Antiquity of the Oceans and Continents |
title_fullStr |
Antiquity of the Oceans and Continents |
title_full_unstemmed |
Antiquity of the Oceans and Continents |
title_sort |
antiquity of the oceans and continents |
publisher |
Mineralogical Society of America |
url |
http://hdl.handle.net/1885/20352 https://doi.org/10.2113/gselements.2.4.223 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Greenland |
genre_facet |
Arctic Greenland |
op_source |
Elements |
op_relation |
1811-5209 http://hdl.handle.net/1885/20352 doi:10.2113/gselements.2.4.223 |
op_doi |
https://doi.org/10.2113/gselements.2.4.223 |
container_title |
Elements |
container_volume |
2 |
container_issue |
4 |
container_start_page |
223 |
op_container_end_page |
227 |
_version_ |
1788059195691499520 |