On July 22, China National Offshore Oil Corporation (CNOOC) announced that the Phase I development of the Kenli 10-2 oilfield cluster — a 100 million-ton-class oilfield in Bohai Bay — has officially commenced production.
As China’s largest offshore shallow lithologic oilfield, its launch marks a significant milestone in the nation’s offshore energy development and plays a key role in safeguarding national energy security.
Located in the southern waters of Bohai Bay with an average depth of approximately 20 meters, the Kenli 10-2 oilfield boasts proven geological reserves exceeding 100 million tons. It is the first 100 million-ton-class lithologic oilfield discovered in the shallow depressions of the Bohai Bay Basin, highlighting the vast potential of lithologic oil and gas exploration in the region.
The Kenli 10-2 oilfield is being developed in two phases. The Phase I project utilizes existing infrastructure and includes the construction of one central processing platform and two wellhead platforms, with plans to drill 79 wells for production. At peak capacity, the project is expected to yield approximately 3,000 tons of oil and gas equivalent per day.
The oilfield also represents China’s first offshore development of a “branch-shaped” heavy oil reservoir, characterized by reserves that are scattered, narrow, thin, and complex.
CNOOC Tianjin company has developed an advanced heavy oil recovery system rare globally through independent R&D, enabling precise mapping of underground reservoirs and accurate injection of high-temperature steam to mobilize the oil — laying a solid technical foundation for efficient development.
To address the challenges posed by scattered reserves and highly viscous oil, the project has adopted an innovative approach combining conventional water flooding and steam-based extraction techniques. The central processing platform integrates two production systems for cold and thermal recovery, and is equipped with more than 240 key processing units. It is currently one of the most technologically complex production platforms in the Bohai region and the first large-scale thermal recovery platform in the southern Bohai Sea.
The drilling and well completion project faced multiple challenges, including diverse well types, multilayered formations, varied recovery methods, and heavy oil extraction. In response, the project team introduced an improved workflow that uses seismic data and precise mapping to guide drilling. This raised the success rate of reaching oil-bearing zones by over 30 percent, with some wells extending more than 3,000 meters horizontally — nearly three times their depth —setting a new benchmark in shallow offshore drilling.
The successful commissioning of Phase I of the Kenli 10-2 oilfield cluster signals a new stage in the development of complex offshore heavy oil reservoirs in China. It will also contribute significantly to CNOOC’s goal of achieving an annual output of 40 million tons from the Bohai Oilfield within the year.
(Executive editor: Yuan Ting)
