Oil major loses 7.74b yuan, and PetroChina earnings drop 98% in the first six months

CNOOC Ltd. posted its first-ever half-year loss as crude's plunge and writedowns on assets, including Canadian oil sands, destroyed profit at China's biggest offshore oil and gas producer.

The company swung to a 7.74 billion yuan ($1.16 billion) loss in the January to June period, compared with a net income of 14.7 billion yuan a year earlier, the Beijing-based oil exploration firm said in a statement to the Hong Kong stock exchange on Wednesday. Oil and gas revenue fell 28.5 percent to 55.08 billion yuan.