Aerial view of Daqing, northeast China's Heilongjiang (3)

Aerial photo taken on Sept. 9, 2021 shows the PetroChina Daqing Petrochemical Company in Daqing, northeast China's Heilongjiang Province. China's Daqing Oilfield announced on Aug. 25 the discovery of a major shale oil field with predicted geological reserves of about 1.27 billion tonnes. Discovered in 1959, Daqing Oilfield has made a significant contribution to China's modern petroleum industry system. It also steps up efforts to improve its ecological environment in recent years. (Xinhua/Wang Jianwei)