BEIJING, July 31  -- China National Offshore Oil Corp. Ltd (CNOOC), the country's largest offshore oil producer, announced Thursday that Panyu 10-2/5/8 oil fields have started production.

The oil fields are expected to hit a combined peak production of 13,000 barrels per day by the end of 2015, a company press release said.

The project, which consists of oil fields 10-2, 10-5 and 10-8, is located in the Pearl River Estuary Basin in the South China Sea with an average water depth of about 100 meters.

It was designed to share the existing production facilities of Panyu 4-2 oil field.

Nine new wells and a wellhead platform have been drilled. Four of the wells have started production, with a daily output of about 9,000 barrels of crude oil.

CNOOC owns 100 percent of the oil fields.