China National Petroleum Corp. (CNPC) started to drill its first shale oil well in the southwestern province of Sichuan, the company said in a statement on Aug. 12.

The well, with a designed hole depth of 3,735 m (12,250 ft), attracted 10.62 million yuan (US$1.50 million) investment, according to a document filed to local county government.

Sinopec and CNPC are speeding up drilling and exploration from major tight and shale oil and gas formations in western China to boost domestic output.

However, China’s shale oil, making up less than 1% of the crude output, remains in an early development phase due to challenging geology and hefty development costs.