The deposit is estimated to have approximately 100 million tons of tight oil geological reserves, making it the largest discovery in the region, reported state-run Xinhua news agency.
According to the state-owned energy giant, the deposit will have an annual tight oil production capacity of 700,000t.
However, the China Petroleum Daily reported that the recoverable reserves of the deposit are expected to be significantly lesserto.
Located in the Ordos basin that is estimated to have tight oil production capacity of more than one million tons, the Changqing field has produced six million tons of crude oil in the first quarter of this year.
Integrated international energy company, CNPC holds oil and gas assets and interests in 38 countries.
