China National Offshore Oil Corporation (CNOOC) has started phase one production at the Bozhong 26-6 oilfield development project in central Bohai Bay.

CNOOC holds a 100% interest and operates the project, said to be the largest metamorphic rock oilfield in the world.

A new central processing platform and an unmanned wellhead platform are the main production facilities.

The development plan for the oilfield, which is in an average water depth of around 20m, includes the commissioning of 33 wells, comprising 22 production wells, ten gas injection wells and one water source well.

The field is expected to reach peak production of approximately 22,300 barrels of oil equivalent per day (boepd) by 2025. The oil extracted is categorised as light crude.

The Bozhong 26-6 oilfield contains more than 200 million cubic metres of cumulative proven oil and gas in-place.

CNOOC said it has implemented standardised engineering to undertake the project, resulting in a shortened timeline from discovery to production of just three years.

The Bozhong 26-6 project employs advanced technology to capture and separate CO₂ produced during oil extraction.

This CO₂ is then reinjected into the formation to enhance oil recovery while simultaneously reducing emissions.

Over its lifetime, the project is expected to sequester approximately 1.5 million tonnes of CO₂.

CNOOC president Yan Hongtao said: “The successful commencement of production of Bozhong 26-6 Oilfield Development Project (Phase I) marks a new stage for the company in the development of offshore deep play complicated buried hill oil and gas reservoirs as well as the construction of the Bohai CCUS base.

“It bolsters the company’s energy supply capacity and low-carbon development in the Beijing-Tianjin-Hebei and Bohai Rim regions.”

In January 2025, CNOOC commenced production at the Dongfang 29-1 gas field development project in the South China Sea.

The project is expected to reach peak production of 38 million cubic metres of natural gas per day this year.