Another 100-million-ton oilfield discovery sees light of day in Asian waters

December 24, 2025, by Melisa Cavcic

Chinese state-owned oil and gas giant China National Offshore Oil Corporation (CNOOC) has unveiled a new oilfield find, which it describes as a major discovery in central Bohai Sea off the coast of China.

CNOOC’s latest Qinhuangdao 29-6 oilfield discovery in the shallow Neogene formations of the Bohai Sea is said to add over a hundred million tons of oil equivalent in-place. While the main oil-bearing play is Neogene Minghuazhen Formation, characterized by shallow burial depth, the oil property is medium-heavy crude.

Xu Changgui, CNOOC’s Chief Geologist, commented: “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.”

The 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. The Chinese player claims that the proved in-place volume of Qinhuangdao 29-6 oilfield has exceeded 100 million tons of oil equivalent.

This 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.

The new oilfield discovery comes shortly after CNOOC started production at its oilfields development project in the shallow water of the Pearl River Mouth Basin.