摘要
The formation of the Pre-Tertiary carbonate rocks in Jizhong Depression has gone through multi-phase karstifications. In light of the formation time, cause, and the morph character of the palaeo-karst, 5 models of Palaeo-karstification are recognized as syngenetic karst formed in the interlayer during the formation of the rocks, supergene karst formed in weathered crust during denudation, fracture karst formed in fractures or joints during denudation period, phreatic karst formed under the released water and thermal fluid condition. The development and distribution of the karst fissure and cave system is controlled by the multi-phase karstification, so the paleo-karstifications are of important geologic significance for the formation of the reservoir stratum.