State Key Laboratory of Oil and Gas Reservoir Geology and Exploration Chengdu 610059 China;
No.4 Gas Production Plant of Sinopec Southwest Oil&Gas Company Chongqing 402160 China;
CNOOC(China)Co. Ltd.Shanghai Branch Shanghai 200335 China;
East China Sea Basin; Xihu sag; Paleogene Huagang Formation; tight sandstone; sediment provenance; sedimentary facies belt; diagenetic environment; controlling factors;