SINGAPORE (Reuters) – China’s Sinopec (OTC:) Corp has struck a high flow of oil and gas in an offshore exploration well in the Beibu Gulf of the South China Sea, it said on Wednesday.

The well, Hai-3, a rare slanted well with a drilling depth of 4,600 meters (2.86 miles), tested daily output of 738 cubic metres of and 280,000 cubic metres of , Sinopec said.

The discovery of the shallow-sea well will boost Sinopec’s ongoing development of the Weizhou oilfield in the Beibu Gulf that has proven oil reserves exceeding 10 million metric tons (73 million barrels), Sinopec said in its press release.

Sinopec usually focuses on onshore oil and gas exploration and production but has in recent years stepped up exploring for hydrocarbon resources offshore, which has long been dominated by domestic peer CNOOC (NYSE:) Ltd.