Norwegian energy company Statoil said that, for the first time ever, it was studying the potential reserves off the coast of South Africa.

Statoil, for an undisclosed sum, acquired a 35 percent stake in a frontier basin off the southeast coast of South Africa from a regional exploration subsidiary of Exxon Mobil. The so-called Tugela South exploration basin covers about 3,500 square miles. Water depths are up to 1.1 miles.

The farm-in marks the first time Statoil gained access to South African reserves.

"This opportunity is in line with Statoil's exploration strategy of access at scale," Nick Maden, a regional vice president for Statoil, said in a statement. "It represents access into a frontier basin where we believe we see indications of an active petroleum system and which has impact potential."

Statoil offered no estimate of the reserve potential in South Africa. A report from the U.S. Environmental Protection Agency finds the country has limited proven reserves of oil and natural gas. It may hold what the EIA characterized as "notable" shale gas reserves onshore. All of its estimated 15 million barrels of proved oil reserves are located offshore.

Total oil production in 2014 averaged about 160,000 barrels per day. By comparison, Libya, the worst performing member of the Organization of Petroleum Exporting Countries, produced an average 371,000 bpd last month.

Statoil said work through 2017 would focus on seismic and geological studies in order to get a better understanding of the reserve potential offshore South Africa.