Assembling Australia: Proterozoic building of a continent

• Published in: Precambrian research 2008-10, Vol.166 (1), p.1-35
• Main Authors: Cawood, P.A., Korsch, R.J.
• Format: Article
• Language: English
• Subjects: Accretion; Albany–Fraser; Australia; Backarc; Capricorn; Craton; Diamantina Craton; Great Southern Continent; Halls Creek; Musgrave; North Australian Craton; Orogen; Orogeny; Paterson; Pinjarra; Proterozoic; Proto-Australia; South Australian Craton; Tectonics; Terra Australis; West Australian Craton
• ISSN: 0301-9268; 1872-7433
• DOI: 10.1016/j.precamres.2008.08.006

The western two-thirds of Australia is underlain by Precambrian rocks that are divisible into three Archean to Paleoproterozoic cratons, the West Australian, North Australian and South Australian cratons, separated by Paleoproterozoic to Mesoproterozoic orogens. Prior to about 1500 Ma, the North Australian and South Australian (along with extensions into Antarctica) cratons show a similar geological history and are herein assumed to have evolved as a single entity, termed the Diamantina Craton. The temporal and spatial record of Proterozoic rock units and orogenic events documents accretion and assembly of Precambrian proto-Australia. The Archean Yilgarn and Pilbara cratons were assembled into the West Australian Craton along the Capricorn Orogen during the late Paleoproterozoic (2000 Ma) Glenburgh Orogeny, which then combined with the North Australian segment of the Diamantina Craton along the Paterson Orogen during the 1800–1765 Ma Yapungku Orogeny to form proto-Australia. It was bounded throughout most of the late Paleoproterozoic to earliest Mesoproterozoic along its south western and probably its north eastern margins by subduction zones such that much of the craton occupied an upper plate, backarc basin environment. After ∼1500 Ma, proto-Australia differentiated into two cratonic masses, the combined North Australian and West Australian cratons and the Mawson Craton, consisting of the South Australian Craton and extensions into Antarctica. This breakup, through rotation and lateral translation of the Mawson Craton, resulted in convergence and collisional suturing with the West Australian Craton along the 1345–1140 Ma Albany–Fraser Orogen. The integrated continental assemblage of West Australian, North Australian and South Australian (including parts of Antarctica) cratons are herein referred to as the Great Southern Continent, which persisted until final breakup of Pangea associated with the current northward drift of Australia. The Pinjarra Orogen developed along the margin of the West Australian Craton and records late Mesoproterozoic to Neoproterozoic strike-slip juxtaposition of India within an assembling Gondwana. The Neoproterozoic record of the Terra Australis Orogen, which extends along the eastern side of Precambrian Australia, records rifting and continental breakup within the supercontinent of Rodinia. Australian Proterozoic rocks host significant mineral resources, including world class banded iron-formations in the West Australian Craton