Plate tectonic limits on the assembly of cratonic Australia

Continuous Proterozoic plate reconstructions consistent with plate geodynamics were designed to reconcile data, conceptual models, and human imagination as applied to the assembly of the Australian craton. The reconstructions were created using GPlates and considered available magmatic and metamorphic U-Pb zircon data. Two tectonic scenarios for the Paleo- to Mesoproterozoic assembly of the cratonic lithosphere of Australia were tested for their geodynamic and geochronological viability. The scenarios are founded on tectonic events that are relatively well-established and well-supported by data, but also with several periods and areas that are disputed mostly due to scarcity of data. For these scenarios, we test geodynamic criteria to explore a) which possibilities are better supported by our geodynamic criteria, and b) the implications of those models for the larger-scale plate tectonic setting. The time frame in this model set includes assembling two supercontinents, Nuna (1900–1800 Ma) and Rodinia (1300–900 Ma), and the transition between them. Model 1 presents a progressive assembly of the Australian continent between 2000 Ma and 1300 Ma, showing events in the West Australian Craton (WAC), the convergence of the WAC and the North Australian Craton (NAC), and then accretion at the margin of the South Australian Craton and NAC until collision in the Albany-Fraser Orogen (AFO). Model 2 suggests WAC was separate from the rest of the Australian Craton until 1300 Ma and all combined in one orogenic cycle. It proposes Andean-type subduction along the E and NE margins of the WAC for 40–60 million years as the means of final assembly. Both models are geodynamically plausible, yet each lacks sufficient data support to conclusively resolve the differences and deepen our understanding of the Proterozoic assembly of Australia.