CHONGQING, Oct. 10 -- The Fuling shale gas field in southwest China's Chongqing Municipality has produced over 60 billion cubic meters of natural gas since it began commercial production, according to Sinopec, its developer and China's largest oil refiner.

Shale gas is an unconventional natural gas that is mainly composed of methane and exists in organic-rich mud shale and its interlayer. It is considered a clean new energy resource.

The Fuling gas field was initially constructed in December 2012 and entered commercial development in March 2014, becoming China's first large-scale shale gas field. It has proven reserves of 900 billion cubic meters and a daily shale gas output of about 23 million cubic meters.

The gas field currently brings green and clean energy to more than 70 cities along the Yangtze River Economic Belt.