Regulators have approved oil and gas testing in the Great Australian Bight this year.

Environmental groups are upset at the prospect of seismic testing near Kangaroo Island and Port Lincoln, which involves firing soundwaves into the ocean floor to detect the presence of oil or gas reserves.

It will give oil companies a better idea about the oil and gas resources beneath the ocean floor.

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has granted permission for tests on a 30,100-square-kilometre area, located 80 kilometres from Port Lincoln and 90 kilometres west of Kangaroo Island between September and November.

Exploration company PGS has been ordered not to interfere with or displace pygmy blue whales, southern bluefin tuna, and southern right whales.

The Wilderness Society says the practice can deafen whales even if they cannot be seen.

“It's obvious that blasting massive amounts of noise constantly for months on end through a water column in a space where animals communicate and navigate and live by sound and sonar, it is obvious that this is going to have a terrible impact on those animals,” the environmental group's Peter Owen has told the ABC.

“I fail to see how you can actually approve this type of seismic activity in the middle of one of the most significant whale nurseries in the world.

“It's totally unacceptable.”

The Greens say the seismic testing is a step on the path to full-scale drilling in the Great Australian Bight.

“Why on Earth would we be wanting to sink oil wells in the Great Australian Bight, put our marine life and beaches at risk and make climate change worse,” Greens Senator Sarah Hanson-Young said.

“We've got to be getting out of fossil fuels and transitioning to a clean, green economy.”

Australian Petroleum Production and Exploration Association spokesperson Matthew Doman says the technology can be used safely.

“We have a very long track record of conducting seismic in Australian waters without impact on the marine environment,” he said.

“Our energy mix is changing, the role of renewable energy is increasing … our industry is very much a supporter of that.

“But we will use a lot of oil and a lot of gas for decades to come.”