Elastic flexure and distributed deformation along Australia'sNorth West Shelf: Neogene tectonics of the Bonaparte andBrowse basins

摘要

Neogene collision between Australia and the Banda Arc modified the adjacent Bonaparte and Browse basins of the North West Shelf of Australia. Modification comprised both continuous long-wavelength amplification of Permo-Carboniferous basement topography and flexure and normal faulting of Triassic—Recent sedimentary cover. Deformation was continu-ous across the Browse and Bonaparte basins, despite the basins beings separated by a rupture-barrier style accommodation zone, the Browse—Bonaparte Transition. The degree of basement control and mechanisms of fault linkage vary significantly across this transition, and reflect differences in the structural relief, amplitude and depth of rifted basement either side of the transition. Neogene collision amplified the architectural divide. Amplification of basement topography over wavelengths of several hundred kilometres was associated with negligible horizontal length change. The transcurrent component of Neogene deformation was partitioned outboard of any continuous flexural amplification.