Exposing basement terranes of the North Australian Craton

Abstract

The North Australian Craton is a significant crustal element of the Australian continent. In this review, we focus on the internal architecture of the North Australian Craton by reviewing the tectonic evolution of basement exposures in the Pine Creek, Tanami, Tennant Creek, Arnhem, and Mount Isa blocks, which we refer to as the proto-North Australian Craton. These sparsely exposed basement blocks are extensively overlain by Late Paleoproterozoic to Mesoproterozoic sedimentary basins. We assess the differences and similarities in magmatism, basin systems, and deformation events of pre-1800 Ma rocks. We reviewed U[sbnd]Pb inherited zircon ages older than 1900 Ma together with Nd geochemical data for pre-1800 Ma magmatic rocks which show that the interior of proto-North Australian Craton is largely homogenous with indistinguishable isotopic and geochemical characteristics of ca 1870–1840 Ma magmatic rocks and similar ca 2050–1870 Ma structural patterns. There are notable differences in deformation styles, metamorphism, and structure trends in the interior of North Australian Craton highlighting the presence of some localized crustal-scale discontinuities and evidence of crustal reworking. We identify several crustal boundaries within individual terranes, whose continuity across the proto-North Australian Craton is often masked by overlying basins.