Study On Influence Factors Of Amplitude-preserving Processing For Prestack Reservoir Prediction

With the constant improvement of the degree of exploration and development,the shallow,middle and deep all become important exploration targets,the lithologic reservoir has become the important exploration objects.The geophysical exploration technology plays an important role in key support,and gradually along with the development of geological research to develop the field of prestack.In deep and complex reservoir study,shallow reservoir physical properties change and fluid properties,etc.,prestack research has become the norm.Prestack reservoir prediction technology research development needs of seismic data to support.But at the moment,for "amplitude preservation" standard of seismic data not been determined.In this paper,on the basis of summarizing the seismic amplitude factors discussed "true amplitude" and "the relative amplitude preservation ",I expound the definition of amplitude preservation processing,and discussed the evaluation standard and qualitative evaluation methods of amplitude preservation processing,introduced the quantitative evaluation method of degree using the correlation coefficient of logo layers reflection wave amplitude curves and amplitude ratio curves.For the whole flow of amplitude preservation processing,analyzed the amplitude preservation degree of each processing module and its influencing factors in theoretical.Then using the data modeled by three-dimensional wave equation method,analyzed the amplitude preservation degree of each processing module and its influencing factors.In the flow of amplitude preservation processing,the purpose of amplitude compensation processing is to make the reflection wave amplitude enable to handle better correspond to the reflection coefficient of underground strata,the amplitude preservation is relatively good.And there are many influence factors of prestack denoising processingis,its amplitude preservation depends on the selection of denoising method and the selection of parameters is or not reasonable.For predictive deconvolution processing,the main influence factor is the prediction step length,if step length is too small the amplitude preservation is poorer,however,if step length is bigger resolution is not good.Therefore,in actual processing step length should be selected according to the specific data to make it reasonable.Kirchhoff integral method prestack time migration has has a certain of relative preserved amplitude,its influence factors are imaging conditions,such as speed precision,migration aperture,processing of regularization should be done before doing prestack migration.