Finds fuel deep-sea oil rush ?
Posted by Big Gav in australia, oil exploration
The Australian has an article on the opening up of some fairly inhospitable oil exploration regions off the south coast of Australia - Finds fuel deep-sea oil rush.
THREE significant new oil and gas regions have been identified off Australia's coast, raising the potential for a wave of offshore exploration that could create booming new resources hubs around the nation.
A combination of new technology and the high price of oil has prompted the commonwealth's Geoscience Australia survey body to push technical limits and explore frontier areas in deep water, turning up startling new resource potential.
One of the regions, the South Australian end of the Great Australian Bight, has been opened for exploration and has already attracted strong bids ahead of the April 29 deadline.
But extracting any oil and gas from this area will mean overcoming significant challenges, including heavy seas and wells deeper than any in operation around the nation.
In addition to the Bight, Geoscience Australia has uncovered strong indications of petroleum in basins near the Lord Howe Rise, 800km east of Brisbane, and on the Wallaby Plateau, 500km off the West Australian coast and next to the existing North West Shelf gas zone.
All three areas are at the deepwater edge of Australia's vast maritime zone - an area almost twice the size of the continent.
Geoscience Australia is using an advanced aeromagnetic survey also to examine basins to the west and north of Tasmania, recently collecting data over a flying distance of 140,000km. The results are being analysed.
With extra funding for frontier exploration, Geoscience Australia has employed an array of technology in the search for resources and has turned up enticing new evidence. It has found potential source rocks in the Bight, which has never produced oil or gas.
The new evidence has emerged at a time of dwindling oil production in Australia, with reserves equal to 10 years of production. ...
Ms Totterdell said the Bight had been regarded as "too hard" by many oil companies, and the rough seas and location of the basin made exploration work in the area "challenging".
In 2003, Woodside Petroleum, the nation's biggest independent oil and gas company, drilled the Gnarlyknots well to a depth of 4000m in the seabed, at a cost of $55m, but it had to abandon the project due to 10m swells. But Ms Totterdell's team was undeterred. They believed the bitumen rocks that washed up on beaches along the coast gave strong indications there was petroleum offshore.
Under Australia's petroleum exploration regime, all information acquired by companies must be given to the federal government. Geoscience Australia re-analysed Woodside's data, and then began looking for rocks in an area about 200km west of where Woodside had drilled.
The rocks were dredged from a 5km-wide canyon that enabled geologists to uncover samples that lie thousands of metres below the seabed in the centre of the basin, about 200km to the east. It is in the centre where the exploration blocks have been offered.
The Bight's water depth ranges from 500m-4000m; the Wallaby Plateau ranges from 2000m to 4000m and Lord Howe Rise ranges from 1300m-2500m.
National oil production has declined from a peak of 35 billion barrels a year early last decade to about 20 billion at present. [BG: these numbers are rubbish - we produce about 210 million barrels of oil per year]