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The Pilbara Craton is an old and stable part of the continental lithosphere located in the Pilbara region of Western Australia. The Pilbara Craton is one of only two pristine Archaean 3.8–2.7 Ga (billion years ago) crusts identified on the Earth, along with the Kaapvaal Craton in South Africa .
Nevertheless, the oldest cratons on Earth include the Kaapvaal Craton, the Western Gneiss Terrane of the Yilgarn Craton (~2.9 – >3.2 Ga), the Pilbara Craton (~3.4 Ga), and portions of the Canadian Shield (~2.4 – >3.6 Ga). Parts of Dharwar Craton in India are greater than 3.0 Ga.
The Yilgarn Craton is a large craton that constitutes a major part of the Western Australian land mass. It is bounded by a mixture of sedimentary basins and Proterozoic fold and thrust belts . Zircon grains in the Jack Hills , Narryer Terrane have been dated at ~4.27 Ga , with one detrital zircon dated as old as 4.4 Ga. [ 1 ]
The cratons appear to have been assembled to form the greater Australian landmass in the late Archaean to Mesoproterozoic, ~2400 Ma to 1,600 Ma. Chiefly the Glenburgh Orogeny is partly responsible for the assembly of the West Australian landmass by joining the Yilgarn and Pilbara cratons. The Glenburgh Orogeny is exposed in the rocks of the ...
East European Craton, the core of Baltica. Volgo-Uralian Craton, Russia (3.0–2.7 Ga) Baltic Shield, part of the East European Craton; Fennoscandian Shield, the exposed Northwestern part of the Baltic Shield in Norway, Sweden and Finland (3.1 Ga) Karelian Craton, part of the Fennoscandian Shield in Southeast Finland and Karelia Russia, (3.4 Ga)
The Eastern Pilbara Craton is geologically significant due to its age and the types of lithology found within it. Within the Eastern Pilbara Craton there are 2 distinct lithologic divisions: (1), early Earth crust (3.8–3.53 Ga); (2), intrusive granitic domes along with greenstone belts (3.53–3.23 Ga). [3]
The Capricorn orogeny was an orogenic event in what is now Western Australia, following the collision of the Pilbara Craton and the Glenburgh Terrane with the Yilgarn Craton during the Glenburgh orogeny. Spanning one billion years, the Capricorn orogeny is marked by widespread deformation and intracratonal reworking.
The Australian Shield is fractured into a number of distinct blocks, including two cratons - the Pilbara Craton in the North and the Yilgarn Craton in the Southwest. These two cratons are the oldest part of the shield, both of which have been dated at more than 2.3 billion years old. [5]