Amadeus Basin

The Neoproterozoic to Carboniferous Amadeus Basin is a large intracratonic sedimentary basin initiated as part of the Centralian Superbasin and substantially affected by intraplate tectonics. It overlies the Palaeoproterozoic Warumpi and Palaeo-Neoproterozoic Aileron provinces to the north and Mesoproterozoic Musgrave Province to the south and is overlain by the Mesozoic Eromanga and Phanerozoic Pedirka basins to the southeast.  The present-day Amadeus Basin is a structural remnant of a broad, shallow basin – it has been significantly tectonically modified during two major intracratonic orogenic events: the 580– 540 Ma Petermann Orogeny and the 450–300 Ma Alice Springs Orogeny. The Amadeus Basin sedimentary stratigraphy is dominated by dolostone, limestone, shale, sandstone, siltstone, quartzite, evaporite, diamictite, and conglomerate sequences.

The first significant technical petroleum discoveries in the Territory were in the Amadeus Basin.  Ooraminna-1 encountered a sub-commercial gas flow in 1963 followed by the discovery of the Mereenie oil and gas field in 1963 and Palm Valley gas field in 1964. Increased levels of exploration activity occurred in the 1980s and early 1990s, resulting in the discovery of the Dingo gas field in 1981 and several other technical discoveries. Production commenced in the Palm Valley and Mereenie fields in 1983 and 1984 respectively, and commenced in the Dingo gas field in 2015. All three gas fields are currently producing. Exploration to further develop the deeper parts of the existing fields and assess the potential for large sub-salt petroleum, hydrogen and helium plays is ongoing.

Central Petroleum Ltd operates all the producing fields within the Amadeus Basin.

2023 annual petroleum production of 13.71 billion standard cubic feet (bscf) of gas comprising:

• Mereenie - 8.77 bscf of gas and 0.12 million barrels of oil (MMbbl)
• Palm Valley - 3.72 bscf of gas
• Dingo - 1.22 bscf of gas

Total production from the Amadeus Basin to the end of 2023 is 496 bcf of gas and 19.1 (MMbbl).

Annual updated production figures can be found on the Department of Industry, Tourism and Trade website.

The table below lists the best estimate of reserves (2P) and best estimate of contingent resources (2C) using the SPE-Petroleum Resources Management System for producing fields operated by Central Petroleum at 27 July 2023.

1 Central Petroleum net share 25%

2 Central Petroleum net share 50%

Petroleum

The Amadeus Basin has substantial potential for the discovery of further conventional oil and gas resources. There are up to five conventional petroleum systems, including the Ordovician system that hosts the Mereenie and Palm Valley fields within the Larapinta Group rocks. Gas potential has also been identified at the Orraminna gas field, Magee-1, Orange  and West Walker-1 gas prospects (Munson, 2014). The Neoproterozoic lower Gillen-Heavitree System at the base of the basin also has potential for large scale sub-salt hydrocarbon plays.

Other energy potential

The Amadeus Basin is also highly prospective for naturally occurring hydrogen and helium within the sub-salt and intra-salt plays of the Neoproterozoic lower Gillen-Heavitree System in the southeastern part of the Basin.

The Amadeus Basin is also prospective for geothermal energy with potential high heat flow from the underlying basement rocks of the Warumpi Province and Musgrave Province rocks. The proximity to existing infrastructure also increases the potential of the Basin. Read more on the Geothermal energy potential of the Northern Territory.

The potential for geological carbon capture and storage in the Amadeus Basin is supported by the presence of porous sandstone and carbonate reservoirs and excellent seals of halite and anhydrite.

Mineral commodities

For an overview of the mineral prospectivity view the Geology of the Northern Territory Chapter 23 Amadeus Basin and the mineral commodities pages.

Central Petroleum Ltd continues to invest in deeper exploration targets to define further reserves, as well as exploration to target sub-salt and intra-salt plays for helium and hydrogen accumulations. In September 2023, Central Petroleum announced that farm-out agreements with Peak Helium Pty Ltd, covering helium, hydrogen and hydrocarbon exploration in the southern Amadeus Basin, had been terminated. As a result, planning has been suspended for drilling of sub-salt exploration wells to be operated by Santos (Dukas; EP112), Jacko Bore (formerly Mt Kitty; EP125) and Mahler (EP82). Greenvale Energy Ltd announced it had executed a farm-in agreement with Mosman Oil and Gas Ltd to earn up to 75% in EP145, located east-southeast of Mereenie. EP145 has Best Estimate Prospective Resources of 440 Bcf gas, 26.4 Bcf helium and 26.4 Bcf hydrogen in the permit area.

For more detail view onshore exploration activity .