Abstract

The present upper crustal composition of the Earth is attributed largely to intracrustal differentiation, resulting in the production of K-rich granites. The crust grows episodically and it is concluded that at least 60 per cent of it was emplaced by the late Archaean (ca 2.7 Ae). Archaean tonalites and trondhjemites resulted from slab melting of young hot oceanic crust. In contrast, most subduction-related rocks, now the main contributors to crustal growth, are derived from the mantle wedge above subduction zones. The contrast between the processes responsible for Archaean and post-Archaean crustal growth is attributed to faster subduction of younger (hotter) oceanic crust in the Archaean (ultimately due to higher heat flow) compared with subduction of older cooler oceanic crust in more recent times. The terrestrial continental crust appears to be unique compared to crusts on other planets and satellites in the solar system, ultimately, a consequence of the presence of water on Earth.
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Product Type/Sub Type

nonGeographicDataset

Constraints

Creative Commons Attribution 4.0 International Licence

IP Owner

Commonwealth of Australia (Geoscience Australia)

Author(s)

Date (publication)

1997-01-01T00:00:00

Product Type

nonGeographicDataset

Topic Category

geoscientificInformation

GA Catalogue Number

81478 Product http://www.ga.gov.au/metadata-gateway/metadata/record/81478/

Keywords

GA Publication
Journal
Earth Sciences

Resource Language

English

Resource Character Set

utf8

Resource Security Classification

unclassified

Digital Transfer Options

onLine

Distributor

Role
distributor
Organisation Name
Commonwealth of Australia (Geoscience Australia)
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address

Metadata File Identifier

fae9173a-71a3-71e4-e044-00144fdd4fa6

Metadata Standard Name

ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata

Metadata Standard Version

1.1

METADATA SECURITY CLASSIFICATION

unclassified

Metadata Contact

Role
pointOfContact
Organisation Name
Commonwealth of Australia (Geoscience Australia)
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address
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