Conventional vs Unconventional

Australia has abundant supplies of both onshore and offshore conventional and unconventional gas.

Conventional Gas

Conventional gas is found where oil and natural gas have moved into large cracks and spaces between layers of rocks deep below the ground, known as basins. Natural gas is referred to as ‘conventional’ when it has collected in a basin and can be extracted through naturally occurring pressure or pumping. Conventional gas basins can be found onshore in the Cooper basin in South Australia, the Eromanga basin in Queensland, the Perth basin in Western Australia and also in waters off Victoria (Gippsland, Otway and Bass basins) and Western Australia (Carnarvon, Browse and Bonaparte basins).

When natural gas occurs in tiny pores (spaces) within some underground formations of shale, sandstone, and other types of sedimentary rock, it’s harder for the gas to migrate or flow naturally. This means different methods are required for extraction, such as horizontal drilling and hydraulic fracturing.

Unconventional Gas

The development of unconventional gas resources reached commercial levels in the mid-1990s with the commencement of coal seam gas production in Queensland. More than 90 per cent of Queensland’s gas supply is now sourced from coal seams in the Surat and Bowen basins.

The first shale gas well was drilled in the Cooper Basin in 2012. Unconventional resources have also been identified in Western Australia, South Australia, the Northern Territory and Victoria, with varying levels of exploration and development taking place.

Types of gas wells