Type and distribution of Mid-Permian Maokou Formation karst reservoirs in southern Sichuan Basin, SW China

HUANG Shipeng,JIANG Qingchun,FENG Qingfu,WU Ya,LU Weihua,SU Wang,CHEN Xiaoyue,REN Mengyi,PENG Hui

Fig. 3. Characteristics of the pores, vugs and fractures in different types of reservoirs in the Maokou Formation, southern Sichuan Basin. (a) Well WY28, P2m4, 1 518.20-1 518.35 m, bioclastic limestone, with rich vugs, core picture; (b) Well B30, P2m3, 3 135.56 m, bioclastic limestone, vugs filled by pyrobitumen, core picture; (c) Well B30, P2m3, 3 139.09-3 139.20 m, sparry bioclastic limestone, with rich vugs, core picture; (d) Well WY17, P2m2a, 1 713.04-1 713.22 m, sparry bioclastic limestone, with visible vugs and few fractures, core picture; (e) Well B003-X5, P2m3, 3 650.00-3 653.00 m, with abundant vugs, imaging logging; (f) Well B003-X5, P2m3, 3 655.00-3 658.00 m, abundant dissolved vugs, imaging logging; (g) Well B20, P2m2b, 3 649.30 m, bioclastic limestone, with intercrystalline dissolution pores, cast thin section; (h) Well B35, P2m3, 3 561.01-3 561.21 m, bioclastic limestone, with high angle fracture partially filled by calcite, core picture; (i) Well B20, P2m2b, 3 655.43-3 656.48 m, caves filled by calcite and collapse breccia, core picture.