The discovery well LK7-1-1 was drilled and completed at a depth of about 4,400 meters and it encountered a total of 76 meters of oil and gas pay zones, CNOOC said.
CNOOC has invested heavily in the development of China's offshore oil and gas reserves, as part of a broader push to offset declining output from aging onshore fields.
"The successful well demonstrates the broad exploration prospect in Mesozoic volcanic rocks in Bohai Bay," Xu Changgui, Deputy Chief Exploration Officer of CNOOC said.
"It also testifies the progress in the company's understanding and technological capabilities in tapping resources in medium-to-deep plays," he added.
