China National Offshore Oil Corp's announcement of a major oilfield discovery in the Bohai Sea is expected to add over 100 million metric tons of oil equivalent, and further develop offshore oil and gas resources in the country, industry experts said.

CNOOC announced on Monday the discovery of Qinhuangdao 27-3 oilfield, which is located in the north-central waters of the Bohai Sea.

The proved in-place volume of the oilfield has reached 104 million tons of oil equivalent through continuous exploration, it said.

"Qinhuangdao 27-3 oilfield is another major discovery with proved in-place volume of over 100 million tons that we made in the north-central Bohai Sea in a decade," said Xu Changgui, deputy chief exploration officer of CNOOC.

"The successful discovery of the oilfield further demonstrates the oil and gas exploration potential in the complicated strike-slip fault zones of the Bohai Sea."

According to CNOOC, the field has been tested to produce about 742 barrels of crude oil per day from a single well.

The discovery well QHD27-3-3 was drilled and completed at a depth of 1,570 meters, which encountered a total of 48.9 meters of oil pay zones, it said.

Investment in offshore oil and gas exploration is expected to rise further, with more than half of this year's domestic oil increment likely to come from offshore sources, said Li Ziyue, an analyst with BloombergNEF.

China's offshore oil and gas production is expected to further increase in 2024, she added.

The nation's investment in offshore oil production rose last year, with key development projects and offshore oil and gas production reaching new highs, said Wang Zhen, head of the CNOOC Energy Economics Institute.

China's continuous commitment toward upstream investment and production has played a critical role in the country's energy security.

According to China Offshore Oil Engineering Co Ltd, the nation's leading offshore contractor, its revenue last year hit a record high of more than 30.75 billion yuan ($4.27 billion), as the company accelerated domestic production while expanding its foreign market share.

Net profit rose to 1.91 billion yuan, compared with 1.45 billion yuan in 2022, a record high in seven years, it said.

According to Zhou Xinhuai, CEO and president of CNOOC Ltd, the company has been making new discoveries in the Bohai Sea, which has further expanded the resource base for growth in offshore oil production.

CNOOC will focus on increasing reserves and production to enhance China's energy supply capacity, thereby contributing to the sustainable development of the economy and society, Zhou said.