China Petroleum & Chemical Corp has achieved a record-breaking single-well peak daily oil production of 262.8 metric tons at their Jiyang shale oil demonstration zone in Shandong province, setting a new national record for shale oil daily production per well.

The Jiyang shale oil zone, which is part of the Shengli oilfield, has an estimated shale oil resource of 10.5 billion tons, of which 1.73 billion tons have been identified as prospective reserves, said the company, also known as Sinopec.

Shale oil remains among the geologically most challenging and costly types of oil to explore and produce in China, despite the huge resource size, with output making up only 1 percent of China's total crude oil production.

zhengxin@chinadaily.com.cn