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Geological Survey of Western Australia, Mineral House, 100 Plain Street, East Perth, Western Australia, 6004
The Pilbara Craton is a discrete and coherent body of well preserved and exposed early continental crust in the northwestern part of the Australian continent, with a present surface area of about 180 000 km2. It has two tectonostratigraphic components: an older ‘basement’ of granite-greenstone terrane, formed between about 3.5 and 2.9 Ga, unconformably overlain by a supracrustal sequence, the Mount Bruce Supergroup, laid down between about 2.8 and 2.4 Ga in the Hamersley Basin. The main body of the craton has retained its integrity since that time, and has undergone only regional uplift, mild metamorphism, and gentle folding. A tendency to interpret the geology of the craton in terms of paradigms, involving a simplistic comparison with other areas thought to be better understood, has impeded the development of independent hypotheses of crustal evolution based on objective integration of observational evidence from within the Pilbara craton itself.
