Abstract: On the basis of the pool-forming theory and conditions for shale gas in the United States,the controlling factors for shale gas accumulation were analyzed and divided into internal and external factors.The internal control factors include the type,content and maturity of organic matters,and the fracture,porosity,permeability,mineral composition,thickness,humidity of shale.The external control factors include reservoir depth,temperature and pressure of formation.Among them,the type,content and maturity of organic matters,as well as the fracture,porosity and permeability of shale are the main factors for generating shale gas reservoir.The favorable areas for developing shale gas reservoirs were predicted by using parameter model.The analogical analysis based on the model suggests that the Cambrian system and the Silurian system are the most favorable strata for developing of shale gas reservoirs among the marine Paleozoic strata in South China.The most favorable areas of the Cambrian are located in Sichuan Basin,the Micangshan-Dabashan foreland,the northern Guizhou Province,West Hunan Province,East Chongqing and the north part of Jiangnan uplift.The most favorable areas of the Silurian are located in Sichuan Basin,the Micangshan-Dabashan foreland and East Chongqing,West Hubei Province of Upper-Yangtze River,North Hubei Province of Middle-Yangtze River and South Jiangsu Province of Lower-Yangtze River.The indexes of shale in the favorable areas were analyzed to provide reference for early evaluation of shale gas in China.

Key words: shale gas, controlling factors, South China, Cambrian system, Silurian system, favorable areas of shale gas

摘要： 在系统研究美国页岩气成藏理论和成藏条件的基础上,分析了页岩气成藏的主要控制因素,分为内部因素和外部因素:前者指页岩本身的因素,包括有机质类型和含量、成熟度、裂缝、孔隙度和渗透率、矿物组成、厚度、湿度等;后者主要包括深度、温度和压力等。其中,有机质类型和含量、成熟度、裂缝及孔隙度和渗透率是控制页岩气成藏的主要因素。结合主要影响参数,建立了预测页岩含气的种类、比例和页岩气藏发育有利区的参数模型。运用此模型类比研究发现,中国南方古生界海相页岩层中,寒武系和志留系是页岩气发育的最有利层系。寒武系页岩气藏发育最有利区位于四川盆地和米仓山—大巴山前陆以及渝东、黔北、湘西—江南隆起北缘一线;志留系页岩气藏发育最有利区位于上扬子的四川盆地和米仓山—大巴山前陆和渝东—鄂西一带、中扬子鄂北以及下扬子苏南等地。并对各有利区的泥页岩指标进行分析,以期为中国页岩气早期评价提供参考。

关键词: 页岩气, 主控因素, 中国南方, 寒武系, 志留系, 页岩气有利区