The discovery was made at the Qinhuangdao 27-3 oilfield located in the north-central waters of the Bohai Sea, the company said in a statement, opens new tab. The field has been tested to produce about 742 barrels of crude oil per day from a single well, it added.
Earlier in the month, CNOOC announced the discovery of a new reserve in the South China Sea, which contains over 100 million tons of oil equivalent proved in-place.
The announcements come as CNOOC invests heavily in the development of China's offshore oil and gas reserves as part of a broader push to offset declining output from aging onshore fields.
The oil and gas giant in January raised its 2024 production target by about 8% to a record 700 million to 720 million barrels of oil equivalent, citing higher annual capital spending, with production reaching about 675 million boe in 2023.