The term oil encompasses the range of liquid hydrocarbons and includes crude oil and condensate:
- Crude oil is a naturally-occurring liquid consisting mainly of hydrocarbons derived from the thermal and chemical alteration of organic matter buried in sedimentary basins. It is formed as organic-rich rocks are buried and heated over geological time.
- Condensate is a liquid mixture of pentane and heavier hydrocarbons found in oil fields with associated gas or in gas fields. It is a gas in the subsurface reservoir, but condenses to form a liquid when produced and brought to the surface.
Australia has about 0.3 per cent of the world oil reserves. Most of Australia’s known remaining oil resources are condensate and liquefied petroleum gas (LPG) associated with giant offshore gas fields in the Browse, Carnarvon and Bonaparte basins. In addition oil resources are identified in the Perth, Canning, Amadeus, Cooper/Eromanga, Bowen/Surat, Otway, Bass and Gippsland basins.