Effect of Sedimentary Facies Characteristics on Deep Shale Gas Desserts: A Case from the Longmaxi Formation, South Sichuan Basin, China

Shale gas is one of the hot spots energy development. Due to strong heterogeneity and low physical properties shale reservoirs, complex influencing factors pore development, it necessary conduct a comprehensive analysis control high-quality reservoirs. The sedimentary characteristics, mineral composition, structure controlling high quality reservoir development are studied on basis thin section, scanning electron microscopy (SEM) QEMSCAN analysis, X-ray diffraction (XRD), total organic carbon (TOC), Nano-CT Low-pressure N2 adsorption (N2GA) samples from Longmaxi Formation in South Sichuan Basin. results show following: (1) According lithology, structure, content six microfacies can be divided. (2) Organic matter pores developed organic-rich siliceous silty at bottom first member formation, with average porosity more than 5% permeability 2 × 10−3 μm2, which conducive formation (3) contents TOC positively correlated specific surface area, while carbonate clay minerals negatively quality. (4) In water depth becomes shallower top, environment changes reduction an oxidation environment. decrease, opposite trend. difference affects distribution controls reservoir.