As ultra-deep well surpasses oil & gas target, another drilling ‘breakthrough’ pops up offshore China

Chinese state-owned oil and gas giant China National Offshore Oil Corporation (CNOOC) has celebrated the performance of its first ultra-deep well in Bohai Bay, said to have outperformed its set oil and gas target, alongside a new hydrocarbon discovery, which the firm describes as a “major exploration breakthrough.”

CNOOC claims its D1 well at the Bozhong 19-6 condensate gas field has achieved a high yield. This well, believed to be the first ultra-deep one in Bohai Bay drilled to a depth of 6,088 meters, produces approximately 6,300 barrels of oil equivalent per day.

Sun Fujie, Vice President of CNOOC, remarked: “The high yield well further confirms the promising potential of offshore deep buried hill plays. The exploration and development of oil and gas resources in the deep plays is expected to accelerate. With the new production, the company is continuously bolstering its ability to supply clean energy to the Bohai Economic Rim.”

Located in central Bohai Bay, with an average water depth of about 20 meters, the Bozhong 19-6 field contains proven oil and gas in place of more than 200 billion cubic meters of natural gas and more than 200 million cubic meters of oil.

According to the Chinese energy giant, this is the first gas field of such a size in the deep buried hill play offshore China, thus the firm decided to adopt an “overall planning, phased implementation and pilot first” strategy to develop the field.

Since the company gradually brought on stream Bozhong 19-6 condensate gas field pilot area development project, Phase I development project, and 13-2 Block 5 well site development project in 2020, 2023, and 2024, the gas field is currently producing around 37,500 barrels of oil equivalent per day.

CNOOC also revealed a “breakthrough” in Mesozoic buried hill offshore Bohai Bay with the discovery well LK7-1-1, which was drilled and completed at a depth of about 4,400 meters, encountering a total of 76 meters of oil and gas pay zones.

Xu Changgui, CNOOC’s Deputy Chief Exploration Officer, commented: “In recent years, we have continued to make new discoveries in metamorphic buried hills medium-to-deep plays in Bohai Bay. The successful well demonstrates the broad exploration prospect in Mesozoic volcanic rocks in Bohai Bay.

“It also testifies the progress in the company’s understanding and technological capabilities in tapping resources in medium-to-deep plays. The expertise we gained will guide our exploration in similar plays offshore China.”

Furthermore, the well at the Longkou 7-1 oilfield in eastern Bohai Bay, with an average water depth of about 26 meters, was tested to produce about 210 cubic meters of crude oil and nearly one million cubic meters of natural gas. CNOOC sees this as “a new record” for gas-tested productivity in Bohai Bay.

Zhou Xinhuai, CEO and President of CNOOC, highlighted:  “CNOOC Limited will continue to think out of the box, to deepen our geological understanding and foster technological innovation. We will ramp up our efforts in oil and gas exploration and development, to lay a solid foundation for stable supply of energy to the society and for the high-quality development of the company.”

This is aligned with the firm’s business strategy and development plan for 2024. Recently, CNOOC bolstered its low-carbon efforts by bringing online the first oilfield in the South China Sea, which is receiving power from shore.