PALEOGEOGRAPHY AND FACIES OF JIALINGJIANG PERIOD, EARLY TRIASSIC IN SICHUAN BASIN

As viewed from petrographic facies, the facies belts and regions of favourable reservoir from Jialing Jiang Period of Early Triassic are discussed in this paper. According to the analysis of petrographic classification, the depositional model of Jialingjiang Formation is a rising carbonate platform which has its own features as compared with Bahama Platfrom in North America. Longitudinally, it has undergone twice marine transgressions and regressions, formed two sets of depositional cycles and suites of source, reservoir and cap-rock sequences. It is believed that the area between east part and surrounding regions of Luzhou Uplift and Huayingshan, Jiyaoshan is the major petroliferous province and is a subtidal beach developed area between the platform and the platform basin margins. The main producing formation are the 1st, 3rd members, as well as the local formation of the 4th and 5th members of Jialingjiang Formation. Therefore, this area is a promising prospect in oil and gas.