South Australia is on the verge of the biggest mining boom in the state's history, Premier Mike Rann says.

With exploration at an all-time high, Mr Rann said the next 40 years would be dominated by mining with the potential for thousands of jobs to be created.

Finding people to fill those jobs would be one of the great challenges to have, he said.

"We are on the edge of the biggest mining boom South Australia has ever seen," the premier told ABC Radio.

His comments follow the federal government's deal yesterday with mining company Oxiana to allow it to conduct operations in the Woomera Prohibited Area (WPA), in South Australia's far north.

The company has identified a large copper and gold deposit in SA and is expected to soon get a formal go-ahead for the project from the state government.

BHP Billiton is also pushing ahead with a plan to double the size of the Olympic Dam uranium and copper mine.

A $500 million feasibility study is underway and if approved the development could create up to 23,000 (23,000) jobs.

It would also provide for a major growth of the nearby Roxby Downs township and construction of the Southern Hemisphere's largest desalination plant on Spencer Gulf.

Other spin-offs include a major boost for the auto industry with BHP expected to place the world's biggest single order for trucks.

Mr Rann said the boom in the mining sector followed state government moves to provide incentives for exploration.

In recent years he said SA had gone from one of the least explored areas in the world to record exploration activity.

"We gave companies an incentive to go out and drill," he said.