March 18 (Reuters) - China's CNOOC Ltd has made a major oilfield discovery in the Bohai Sea, adding over 100 million tons of oil equivalent proved in-place volume, the state-owned oil and gas giant said on Monday.

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. 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. (Reporting by Sameer Manekar in Bengaluru; Editing by Mrigank Dhaniwala and Dhanya Ann Thoppil)