Application Research Of Seismic Inversion And Sweet Spot Prediction Of Shale Gas Reservoir

Whether shale gas horizontal well drilling can meet reservoir is the basis of fracturing design.In order to maximize the production of a single well,the horizontal drilling is usually selected in the comprehensive "sweet spot" zone,and the perforation and fracturing are selected in the "sweet spot" box section.Therefore,in the later exploration and development of shale gas,the "sweet spot" prediction and comprehensive evaluation of reservoir play a fundamental and key role.For well area A of the Taiyang anticline structure,the research work is based on the data quality evaluation,combined with a variety of attributes and technical means,to carry out the interpretation work,obtain the regional structural morphology and fault distribution characteristics,and then evaluate the fault classification.Based on the shale analysis of Longmaxi-Wufeng Formation,starting with the geological characteristics and geophysical response analysis of shale gas,the pre-stack inversion method is used to predict the shale reservoir evaluation index.The fracture distribution characteristics,formation pressure and in-situ stress of shale are further predicted.On the basis of the above work,combined with the analysis of geological characteristics and preservation conditions of the work area,the "sweet spot" prediction and comprehensive evaluation of shale gas in this area are carried out.In general,the geological and engineering indicators of the target layer in the work area are good,and three types of favorable areas are selected: the class I "sweet spot" favorable areas are located in the Taiyang anticline,the Yunshanba syncline,and the J well area;Class II favorable area is located in the core of the hanging wall of the Taiyang fault,Yunshanba-Baiyangping syncline and the complex fault zone in the west of the work area;Class III favorable area is located in the Xuyong syncline in the north of the work area and the Taiyang fault in the middle.