GEOLOGICAL FACTORS AND PROCESS IN ENRICHMENT AND HIGH PRODUCTION OF SHALE GAS

Based on referring to a large number of Chinese and foreign literatures,considering the peculiarity of shale gas reservoir and combining with the horizontal comparison with other shale gas reservoir,this paper focuses on analyzing and summarizing the geological factors in enrichment and high production of the Mississippian Barnett shale gas in the Fort Worth Basin of United States.Finally,the related conceptual model of geological process is proposed in order to offer a little inspiration for the assessment,the exploration and the development of Chinese shale gas,which will come.By the analysis of the influential factors,it is concluded that the thermal maturity,the factors which exist?in shale and make it fractured more easily and the validity matching of the two aspects are the most important factors that determine the enrichment and high production of shale gas.The geological process can be summarized into three stages: the first stage is that organic matter is in low maturity,micro-fractures are opened and biogenic gas is effusion;the second stage is that organic matter is in high maturity,micro-fractures are cemented and the cracked gas is enrichment;the third stage is that micro-fractures are reopened and the shale gas is highly produced under hydraulic fracturing.