Australia is flanked by a vast area of continental margin incorporating 16 deeply submerged plateaus, terraces, and rises, which are largely unexplored for petroleum. Some are now within range of drilling and well-completion technology.

Most of these features are rifted and foundered continental blocks on which sediment thicknesses range from about 500 to 9,000 m. However, in many areas the marine sequence deposited after continental breakup is thin.

The most prospective areas, the Exmouth Plateau and the Carnarvon and Rowley Terraces off Western Australia, are underlain by several thousand meters of mainly fluvial-deltaic riff-stage sediments, which may provide reservoirs and gas-prone source beds. A transgressive marine mudstone is believed to provide the main source beds and seal. Fair prospects are assigned to three features offshore of Queensland--the Queensland and Townsville Troughs and a depocenter flanking the Marion Plateau. The Ceduna Terrace off southern Australia also warrants further exploration. Rift-basins which may occur beneath the South Tasmania Rise, Lord Howe Rise, Kenn Plateau, Eastern Fields Plateau and other areas off northeastern Australia, require further surveying, as they may provide long-term prospects for petroleum.