摘要
The exploration history of Middle Triassic Leikoupo Formation is about 40 years in Sichuan Basin, but there are only two large-and medium-sized gas pools found till today. The reservoir rocks of Middle Triassic gas pools are mainly located in the base and top of the formation with low-medium porosity and low permeability, and the hydrocarbon source rocks were Upper Permian Longtan Formation and Upper Triassic Xujiahe Formation, respectively. The component of natural gas in Middle Triassic was varied. The main reservoir spaces are various secondary dissolved pores, and the reservoir type is porous or fractured-porous. The sealing of gas pools is well-developed with good direct and indirect cap rocks. The reservoir rocks of Upper Triassic Ma’antang Formation are calcarenite and micrite located at the base of the unit, and its source rock and seal are similar to the gas pools in the top of Leikoupo Formation.