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The oldest minerals on Earth are detrital zircon grains from the Yilgarn Craton in the Mesoarchaean (3.2–2.8 Ga) Jack Hills, Western Australia dated to up to 4.4 Ga, meaning that granitic continental crust and probably supracrustal rocks formed during the Hadean, within 200 million years of Earth accretion. Most Hadean rocks were probably ...
Eoarchean geology is the study of the oldest preserved crustal fragments of Earth during the Eoarchean era from 4.031 to 3.6 billion years ago. Major well-preserved rock units dated to this era are known from three localities, the Isua Greenstone Belt in Southwest Greenland, the Acasta Gneiss in the Slave Craton in Canada, and the Nuvvuagittuq Greenstone Belt in the eastern coast of Hudson Bay ...
These rocks are of Archaean and Paleoproterozoic age, ranging from 3.0–1.7 billion years . They form the basement on which the Stoer Group, Wester Ross Supergroup and probably the Loch Ness Supergroup sediments were deposited. The Lewisian consists mainly of granitic gneisses with a minor amount of supracrustal rocks.
See Figure 2 and Table 1 for Examples of Archean felsic volcanic rocks occurrence. All Archean felsic volcanic rocks are distributed in greenstone belts. [6] In Archean cratons, greenstone belts represent supracrustal rocks formed at the Earth's surface and the belts are dominated by volcano-sedimentary sequences.
The belt contains variably metamorphosed mafic volcanic and sedimentary rocks, and is the largest exposure of Eoarchaean supracrustal rocks on Earth. [3] Due to its age and low metamorphic grade [ 4 ] relative to many Eoarchaean rocks, the Isua Greenstone Belt has become a focus for investigations on the emergence of life [ 5 ] [ 6 ] and the ...
The interpretation of S-type granites are that they are sourced from the partial melting of sedimentary rocks (supracrustal) that have been through one or more cycles of weathering. Evidence for this include aluminium and silica enrichment, caused by the weathering process of the source rock.
The oldest supracrustal rocks are the Sebakwian Group (3.5 Ga) exposed around Shurugwi and Mashava, and northwest of Gweru, within the central craton. This group consist of metavolcanic rocks, including komatiite and basalt, banded iron formation, and clastic metasedimentary rocks. The Sebakwian Group is succeeded by the Bulawayan Group ...
The location map of the Dharwar Craton. The shaded area represents the Dharwar Craton. Generated from GeoMapApp (Ryan et al., 2009). [1]The Dharwar Craton is an Archean continental crust craton formed between 3.6-2.5 billion years ago (), which is located in southern India and considered the oldest part of the Indian peninsula.