SINGAPORE, Aug 14 (Reuters) - China's Sinopec Corp said on Thursday the Chinese government has certified an additional 124.6 billion cubic meters (bcm) of geological reserve in th shale field the company operates in southwest China.

Yongchuan field, in the southern part of China's gas-rich Sichuan basin, is buried more than 3,500 m (11,483 ft) below the surface.

The new certification brings the field's total proven reserves, which was first discovered in 2016, to 148 bcm, Sinopec said.

Sinopec, operator of China's first major shale gas field Fuling, also in Sichuan basin, has in recent years been expanding drilling at geologically more complex and deeper formations.

Despite huge resource potential, shale gas remains a small portion of the country's total gas output at roughly 10%.

(Reporting by Chen AizhuEditing by Tomasz Janowski)

((aizhu.chen@thomsonreuters.com; Reuters Messaging: aizhu.chen.reuters.com@reuters.net))