Daqing Oilfield, China's largest oilfield, saw stable production of crude oil and natural gas in 2017, according to the China National Petroleum Corporation.
Crude output in 2017 hit more than 39.5 million tonnes, including 5.5 million tonnes from Daqing's overseas oilfields, which saw an increase of 13.8 percent year on year.
Natural gas production of Daqing exceeded 4 billion cubic meters last year.
Daqing reported 170 million tonnes of new crude oil reserves and 12.4 billion cubic meters of natural gas reserves in 2017.
Discovered in 1959, Daqing oilfield is located in northeast China's Heilongjiang Province. For many years, the oilfield had an annual output exceeding 50 million tonnes of crude oil, but output has shrank due to dwindling reserves.