CNOOC announces major oilfield discovery in Bohai Sea

HONG KONG, Dec. 24, 2025 /PRNewswire/ -- CNOOC Limited (the "Company", SEHK: 00883 (HKD Counter) and 80883 (RMB Counter), SSE: 600938) today announces that the Company has made a major oilfield discovery of Qinhuangdao 29-6 in the shallow Neogene formations of the Bohai Sea, which adds over a hundred million tons of oil equivalent in-place.

Qinhuangdao 29-6 Oilfield is located in central Bohai Sea. The main oil-bearing play is Neogene Minghuazhen Formation, characterized by shallow burial depth. The oil property is medium-heavy crude. The discovery well was drilled and completed at a depth of 1,688 meters, which encountered a total of 66.7 meters oil pay zones and was tested to produce approximately 2,560 barrels of crude oil per day. Through continued exploration, the proved in-place volume of Qinhuangdao 29-6 Oilfield has exceeded 100 million tons of oil equivalent.

Mr. Xu Changgui, the Chief Geologist of the Company, said, "CNOOC Limited has made a significant discovery through enhanced research on hydrocarbon migration and accumulation models in shallow Neogene slope zones, coupled with technological innovation. This achievement challenges the conventional understanding that slope areas merely serve as pathways for hydrocarbons rather than sites for substantial accumulation. It further highlights the considerable exploration potential of uplifted peripheral slopes in settings influenced by intense extensional–strike-slip faulting."

Qinhuangdao 29-6 Oilfield is the second one-hundred-million-ton-class lithological oilfield discovered in the mature exploration area of the Shijiutuo Uplift, further highlighting the value of fine exploration and consolidating the resource base for increasing reserves and production for the Company.