BEIJING – According to China Petroleum & Chemical Corporation, the first phase of the Qijiang shale gas field made a significant Sichuan Basin discovery with a confirmed geological resource of 145.968 billion cubic metres. This big development in Sinopec’s “Project Deep Earth – Natural Gas Base in Sichuan and Chongqing” was made by Sinopec Exploration Company and Sinopec Southwest Oil & Gas Company.
The Qijiang shale gas field is a complicated tectonic zone on the basin’s periphery that contains medium-deep and deep strata, making it the first shale gas field to be found there. Deep shale is shale gas that has been buried deeper than 3,500 metres, and the bulk of Qijiang’s shale deposits have a burial depth of between 1,900 and 4,500 metres. The project encountered numerous difficulties due of the complicated overlaying strata, including a substantially larger depth and changing ground stress.
Sinopec’s team performed more than 10,000 lab analytical tests on the core at a depth of 1,320 metres to address the issue of how a shale gas reservoir was developed in the basin edge under such complicated surface and subsurface conditions. This demonstrated how deep shelf shale pores form and are maintained, showed how deep shale can form large reservoirs with high porosity, and demonstrated the “sweet spots” of projecting deep shale targets.
