1.8-1.5-Ga links between the north and south Australian cratons and the early-middle proterozoic configuration of Australia

The Archaean and Early-Middle Proterozoic (1.8-1.5 Ga) terranes of the North Australian Craton and the South Australian Craton are separated by similar to 400 km of ca. 1.33- 1.10-Ga orogenic belts and Phanerozoic sediments. However, there is a diverse range of geological phenomena that correlate between the component terranes of the two cratons and provide evidence for a shared tectonic evolution between approximately 1.8 and 1.5 Ga. In order to honour these correlations, we propose a reconstruction in which the South Australian Craton is rotated similar to 52degrees counterclockwise about a pole located at similar to 136degreesE and similar to 25degreesS (present-day coordinates), relative to its current position. This reconstruction aligns the ca. 1.8-1.6-Ga orogenic belts preserved in the Arunta Inlier and the Gawler Craton and the ca. 1.6-1.5-Ga orogenic belts preserved in the Mount Isa Block and the Curnamona Province. Before 1.5 Ga, the South Australian Craton was not a separate entity but part of a greater proto-Australian continent which was characterised by accretion along a southward-migrating convergent margin (ca. 1.8-1.6 Ga) followed by convergence along the eastern margin (ca. 1.6-1.5 Ga). After 1.5 Ga, the South Australian Craton broke away from the North Australian Craton only to be reattached in its current position during the ca. 1.33- 1.10 Ga-Albany-Fraser and Musgrave orogenies. (C) 2004 Elsevier B.V All rights reserved.