LD 21-2 is located in the inverted structure belt of LD 22-27 in south Liaodong Bay, with its south part adjacent to LD 27-2 oilfield.

The well was drilled and completed at a depth of 2,831m and encountered oil pay zones with total thickness of about 170m, representing the thickest oil layers found in the exploration of Bohai in recent years, the company said.

The average water depth is 20m.

Oil production currently at the well is around 608 barrels per day.

CNOOC executive vice president and general manager of exploration department Zhu Weilin said, "The discovery of LD21-2 not only has fairly good economics in exploration and development, but also further confirms high quality oil and gas accumulation of the inverted structure belt of LD 22-27 as well as good prospects for future exploration."