Lacustrine Shale Diagenesis—A Case Study of the Second Member of the Funing Formation in the Subei Basin

Shale diagenesis differs from that of sandstone and carbonate rocks with regard to the type, evolution stage, mode. The quality shale reservoirs is closely linked extent diagenetic evolution. This study identifies types characteristics using thin sections scanning electron microscopy (SEM) observations. stages are determined by analyzing organic matter clay mineral transformation establishing a sequence. paper describes comprehensive matter, minerals, clastic particles, minerals determine types, sequences, pore occurring during results show in second member Funing Formation include compaction, dissolution, cementation, metasomatism, dolomitization, syneresis, as well thermal matter. middle A stage prevalent, some areas early B stages. underwent sequence, including collapse shrinkage montmorillonite interlayers stage; rapid formation illite smectite mixed layers, massive hydrocarbon generation matters, dissolution unstable components occurrence fractures filled gypsum, quartz, ferrocalcite, or other authigenic later stage. Dissolution pores dominant Subei Basin. provide new insights into understanding reservoir spaces information for exploration development lacustrine oil gas.