Channel Sand Reservoir Prediction Of The Jurassic Shaximiao Formation In A Certain Area Of ??central Sichuan

In recent years,the Jurassic Shaximiao Formation in central Sichuan Province has achieved breakthroughs in oil and gas exploration.However,the spatial distribution of sand bodies still calls for further study.The main purpose of this study is to start from the geology,well logging,drilling and seismic information,utilize the seismic attribute analysis technology and the seismic inversion technology,predict the spatial distribution regularity of the channel sand bodies and quantitatively characterize their geometric characteristics for the Jurassic Shaximiao Formation in a certain area of central Sichuan Basin,and provide basis for farther breakthroughs in oil and gas exploration of central Sichuan Basin.The following results have been achieved:1.Owing to the lateral anomalies of the amplitude,amplitude compensation has been performed on the three-dimensional post-stack seismic data,which has removed the amplitude errors caused by the influence factors related to the surface and the acquisition system.In addition,the accuracy of reservoir prediction has been improved.2.The seismic modeling for models based on wells in the study area and the theoretical superimposed models of sand bodies has been performed utilizing the split-step Fourier method.The result has been analyzed to identify sand bodies in the study area.3.The types and the proportion of the main developed lithologies in the target stratum of the study area have been calculated according to the lithology interpretation and the response characteristics of different lithologies have been summarized according to the crossplots of the well curves,which has provided a basis for subsequent wave impedance inversion.4.Constraint sparse pulse inversion has been performed on the three-dimensional seismic data and the reliability of the inversion result has been analyzed in comparison with acoustic impedance curves,gamma ray curves and seismic sections.5.The RGB multiple seismic attributes fusion has been utilized to merge the root-mean-square amplitude,the maximum amplitude and the integral amplitude,which are sensitive attributes of the target stratum,to predict the horizontal distribution of the channel sand bodies in the target stratum of the study area.6.The thickness of sand bodies in the target stratum of the study area has been predicted utilizing the inversion result and the difference of the acoustic impedance between sandstone and shale.And the error has been analyzed based on the comparison between prediction and reality.