Study On Engineering Dessert Of Deep Shale Gas By Seismic Inversion Method

With the exploration and development of shale oil and gas production gradually moving to deep and ultra-deep layers,the exploitation of shale oil and gas reservoirs generally requires hydraulic fracturing.During the fracturing process,the rocks constantly produce various forms of fractures and networks,which is conducive to the migration,accumulation and exploitation of oil and gas in fractures and pores.For the development of shale gas reservoirs,the shale gas engineering desserts can be used to evaluate whether the shale reservoir is easy to transform,or the expected effect of the evaluation changes,the brittleness and in-situ stress of the reservoir rocks are two important indicators of the shale gas engineering desserts.This paper introduced the conventional reservoir brittleness index and the representation method of ground stress at first,analyzed the deep shale gas reservoir rock brittleness characteristics and influence factors,and researched deeply the influence of effective pressure on rock brittleness and the two relations,then put forward the suitable for deep coupling of a new type of brittle shale gas reservoir effective pressure indicator factor,and achieved the brittleness prediction of a deep shale gas working area in southwest China.Based on the orthogonal anisotropic media model,the relationship between the curvature attribute and the formation strain is obtained,and the curvature properties of the formation of the formation are calculated through the method of the centrifugal window scanning,and the elastic impedance inversion is carried out using the five dimensional seismic data,and the prediction of the maximum and minimum principal stress and horizontal stress difference and horizontal stress difference ratio is realized.The results showed that the brittleness and effective stress of the deep shale gas reservoir is greatly affected,the higher the effective stress,the lower the reservoir brittleness,and the new brittleness indicator of the effective stress of the coupling,which can be very good indicator of the fracturing index of the formation.On the basis of orthogonal anisotropic media models,the level of the formation of the strata is the maximum and minimum main stress,horizontal stress difference and orthogonal anisotropic stress difference ratio,and the area of the horizontal stress difference is the area of the project for the project.Based on the paper theory,the structure stress of the formation is calculated by using the relationship between the curvature and strain of the formation,and the tectonic stress in the actual area is larger in the top fracture area of the broken anticline.The comprehensive evaluation of the brittle and ground stress of deep shale gas reservoir is evaluated by using the five dimensional seismic data,and the area of the project for the project is found,which can provide accurate guidance for the mining of the future reservoir.