Publications

In 1988, coring carried out during Ocean Drilling Program Leg 122 on the northern Exmouth Plateau discovered Late Triassic reefal carbonates, the first recognised in Australia. Recent follow-up dredging and seismic profiling by the Bureau of Mineral Resources iridicate that Late Triassic to Middle Jurassic reefal buildups are common on the northern Exmouth Plateau and in the outer Canning Basin. Palaeogeographic studies suggest that such buildups are probably also present in the outer Browse and Bonaparte Basins (including the area of the joint Indonesian-Australian Zone of Co-operation), and on other parts of the Tethyan margin, including parts of East Indonesia.The Triassic and Jurassic reefal complexes represent a new exploration play for the North West Shelf region involving reservoirs either in the reefs themselves or associated carbonate platforms. Source rocks could be Triassic shales, Jurassic shales, or lagoonal carbonates. Overlying Cretaceous mudstone or marlstone could form seals. It is suggested that petroleum exploration companies reexamine seismic reflection data acquired on the North West Shelf and adjacent areas for evidence of prospective Mesozoic reefal complexes.