Sinopec Corp. said it struck high-yielding oil and gas in a test well offshore Beibu Bay near China's southwestern coast, marking a rare offshore oil and gas find by the state firm that is largely focused onshore.

The Wei-4 well, some 110 km (68 miles) southwest of the coastal city of Beihai, tested a daily output of 1,264 tonnes of crude oil and 71,800 cubic meters of natural gas at a first layer, after identifying oil-bearing layers nearly a hundred meters thick.

On the second layer, Sinopec struck 1,184 tonnes of daily oil flow and 76,000 cubic meters of natural gas, the company said in a statement on Jan. 6.

The well, drilled in the shallow part of the sea, is 3,783 meters deep. It took 29 days to drill.

"It's a high-flowing offshore test well rarely seen over the last decade," said Sinopec.

China's offshore oil and gas activities have long been dominated by Sinopec's smaller domestic peer CNOOC Ltd.

Before Beibu Bay, Sinopec's limited offshore works were mostly conducted in East China Sea where the firm discovered several natural gas fields.