A new geological shale gas field with a preliminary proven shale gas reserves of 146 billion cubic meters, was discovered in the Qijiang district of Chongqing recently, according to the field's developer, China Petrochemical Corp, or Sinopec, China's largest oil refiner.

The shale gas field, located in a complex tectonic area in the southeastern Sichuan Basin between Chongqing's Qijiang district and Guizhou's Xishui county, was transformed by strong tectonic movement, the company said.

It is the first medium-deep to deep-layer shale gas field to be discovered in the country's complex tectonic basin areas. The buried depth of the shale beds in the field ranges from 1,900 to 4,500 meters, and the underground depth of the field's main section is more than 3,500 meters. It requires high technology for exploration and exploitation because of its complex overburden layers, depth and varied crustal stresses, Sinopec said.

The company has invented a dimensional fracturing technology for connecting the gas networks underground and for extracting the shale gas.

The company said it has 6.3 trillion cubic meters of deep shale gas reserves in the mining area of the Sichuan Basin, which will play an important role in discovering more untapped natural gas reserves and increasing production in the future.

According to the China Natural Gas Development Report 2022, newly proven geological natural gas reserves last year hit 1.63 trillion cubic meters. Geological shale gas reserves reached 745.4 billion cubic meters.