China has discovered deep shale gas reserves in two major gas fields in the southwest, each holding more than 100 billion cubic metres (bcm) of proven reserves, as the country continues its push for greater energy security.The state-owned China Petroleum and Chemical Corp (Sinopec) said late Thursday that the government had certified 165 bcm of natural gas reserves at the Hongxing field, which spans Hubei province and Chongqing municipality.“It proves the Hongxing region’s strong resource...