The significantly different geological processes experienced by the shales in the southern Sichuan Basin provide a means for comparing their pore characteristics and their supercritical methane adsorption capacities. In this study, we analyzed the Wufeng Formation (O(3)w)-Longmaxi Formation (S(1)l) shales in the southern Sichuan Basin using multiple analytical methods, including mineralogy, field emission scanning electron microscopy (FE-SEM), mercury intrusion capillary pressure (MICP), lowpressure gas adsorption (LPGA), and high-pressure methane adsorption. Four types of shale lithofacies were identified including clay-rich siliceous shale (S-3), argillaceous/siliceous mixed shale (M-2), silica-rich argillaceous shale (CM-1), and mixed argillaceous shale (CM-2). With increasing burial depth, the pore system gradually shifted from organic matter (OM) pores to intergranular (interP) pores between the OM clumps and the brittle minerals. The results of the MICP and LPGA were not significantly affected by burial depth, but were closely related to the total organic carbon (TOC) content and lithofacies. The surface areas and total pore volumes (V-p's) varied from 5.44 to 11.73 m(2)/g with an average of 9.89 m(2)/g and from 0.88 to 2.04 cm(3)/100 g, respectively. Patterns in the and surface area values of the S-3 and M-2 samples exhibited four-modal features, while the CM samples were bimodal. The excess adsorption capacity reached its maximum value when the pressure was about 9-11 MPa, and then it decreased as the pressure increased. The mesopores provided the main V-p (average 43.1%), and the micropores provided the main surface area (average 74.38%). The adsorption positions of the gas molecules can be provided by micropores and mesopores, and even by microcracks and macropores, and as the TOC content of the shale increases, the contribution of the micropores to adsorption becomes more significant.