Mesozoic-Cenozoic evolution of Australia's New Guinea margin in a west Pacific context
K. C. HILL, R. HALL, 2003. "Mesozoic-Cenozoic evolution of Australia's New Guinea margin in a west Pacific context", Evolution and Dynamics of the Australian Plate, R.R. Hillis, R.D. Müller
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The northern Australian margin includes the island of New Guinea, which records a complex structural and tectonic evolution, largely masked by Mio-Pliocene orogenesis and the Pleistocene onset of tectonic collapse. In the Palaeozoic, New Guinea contained the boundary between a Late Palaeozoic active margin in the east and a region of extension associated with Gondwana breakup along the western margin of Australia. In the Permian and Early Triassic, New Guinea was an active margin resulting in widespread Middle Triassic granite intrusions. The Mesozoic saw Triassic and Jurassic rifting followed by Cretaceous passive margin subsidence and renewed rifting in the Late Cretaceous and Paleocene. Since the Eocene, New Guinea tectonics have been driven by rapid northward movement of the Australian Plate and later sinistral oblique convergence with the Pacific Plate, resulting in Mio-Pliocene arc-continent collision. Neogene deformation along the margin, however, has been the result of direct interaction with the Philippine and Caroline Plates. Collision with the Philippine–Caroline Arc commenced in the Late Oligocene and orogenesis continues today. We suggest that the New Guinea Mobile Belt comprises a collision zone between a north-facing Cretaceous indented margin and a south-facing Palaeogene accretionary prism, sub-sequently cut by a Neogene strike-slip fault system with well over 1000 km sinistral displacement that has alternated between extension and compression. The change in character of the lithosphere in New Guinea, from thick and strong in the west to thin and weak north and east of the Tasman Line, was also an important influence on the style and location of Mesozoic and Cenozoic deformation.