Application of Seismic Waveform Difference Inversion and Characteristic Parameter Simulation in Shale Gas Dessert Identification

摘要

The marine shale gas work of the Lower Silurian Longmaxi Formation in the Sichuan Basin has entered the stage of large-scale benefit development from the initial resource survey and layer selection stage,and carried out small-scale shale formation division,fine contrast of shale reservoirs and shale.Fine prediction of reservoirs is an urgent need for shale gas exploration-development integration.In this paper,a new method of seismic waveform difference inversion and characteristic parameter simulation is used to realize the well-seismic cooperative high-frequency simulation,to solve the current thin reservoir prediction problem of shale gas exploration,and to accurately predict the 1 small layer of"Dessert of S1L_1~1 +2"Thickness(6-20 m)and characteristic parameters;this method makes full use of the lateral change information of seismic waveforms,better reflecting the influence of sedimentary environment on the reservoir.The practical application shows that the vertical and horizontal resolutions of the method are improved at the same time,and the inversion results are deterministic,which reflects the phase control idea,solves the problem of the current shale gas thin layer dessert identification,improves the drilling success rate and reduces the exploration and development cost;The method is applicable to three-dimensional work areas with few wells and nonuniform distribution,and most of the current shale gas three-dimensional work areas fall into this category.