Shale reservoir characteristics and gas-bearing influencing factors of Wufeng Formation-Long 1 Member in Lintanchang Area,Southeast Sichuan
Taking the organic-rich shale of Wufeng Formation-Long 1 Member in Lintanchang Area,Southeast Sichuan as the research object.By means of X-ray diffraction mineral analysis,kerogen mi-croscopic examination,vitrinite reflectance,porosity,gas-bearing property,trace element test and log-ging interpretation,a comprehensive study is carried out to analyze the influencing factors of gas-bearing property of shale reservoirs.The research results show that the main lithology of Wufeng Formation-Long 1 Member in Lintanchang Area is black carbonaceous graptolite shale mixed with siltstone,which is divided into 9 sub-layers.The kerogen type is mainly type Ⅰ,with R.ranging from 3.27％to 3.47％,TOC ranging from 0.58％to 6.43％,porosity ranging from 0.52％to 10.81％and permeabili-ty ranging from 0.002 × 10-3 to 0.684 × 10-3 μm2.The gas content is between 1.12 and 3.85 m3/t.The sedimentary environment as a whole is a transition from deep-water shelf facies to shallow-water shelf facies,with hot and humid climate,anoxic reduction environment and good reservoir properties.The most favorable burial depth for the benefit development of shale gas exploration wells is 2.0-3.0 km,and the burial depth in the south area of Lintanchang is 2.5-4.0 km,indicating that the burial depth is moderate.The distance between shale gas well and fault is more than 1.2 km,and the test production of gas well is proportional to the fault distance.The actual exploration shows that there are five large-scale faults in the range of 2.0 km near well LY1,but only one medium-scale fault in the range of 2.0 km near well LY3,so the test production of well LY3 is higher than that of well LY1.This study provides some guidance and reference for the exploration and development of shale reservoirs in complex structur-al areas of Southeastern Sichuan.
万方数据
维普
