The Great South Basin
The Great South Basin is one of New Zealand's largest undeveloped offshore basins. Situated to the east and south of Southland the Great South Basin was explored between 1976 and 1984 with eight wells drilled. Hydrocarbons were present in half of these. The strong geological similarities with the producing basins of Taranaki and South Australia, combined with the presence of hydrocarbons in four of the eight wells, make the Great South Basin one of New Zealand's largest prospects for both oil and gas.
In July, 2007 the New Zealand Government awarded oil and gas exploration permits for four areas of the Great South Basin, situated in the volatile waters off the Southern Coast of New Zealand. In 2014 Shell NZ, and its associated consortium partners announced, they would undertake exploration drilling in the Great South Basin.
The Great South Basin lies offshore from the coast of Southland and South Otago, and at over 500,000 sq km is one of New Zealand’s largest petroleum basins (covering an area 1.5 times New Zealand’s land mass). The current area of awarded permits covers 18% of the basin.
Recent data indicates that the Great South Basin may have the greatest petroleum volume potential of all New Zealand’s basins. In particular it has the thick sediments required to produce hydrocarbons, favourable reservoir and source rocks, and is not affected by large scale seismic faulting found in most New Zealand basins.