The first appearance of subduction-related igneous rocks occurred at ~540–530 Ma in the Tasmanides ~535–530 Ma in the Tiger Arc of northern Victoria Land and 550 Ma in southern Victoria Land of the Ross Orogen. Detailed correlations between these elements suggest that the onset of convergence was essentially simultaneous along the margin over an original distance of ~1000 km. New insights into the Late Precambrian-latest Devonian evolution of the Pacific margin of Gondwana are obtained by treating the margin in terms of three key tectonic elements: i) the in situ part of the Ross Orogen of Eastern Antarctica (Wilson Terrane) built on, and fringing, older crust ii) the largely in situ southern Tasmanides of eastern Australia and iii) offshore basement and island arc terranes now accreted either to the Ross Orogen, the Tuhua Orogen of southwestern New Zealand or, in one case, to the Australian Tasmanides.
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