The Research Of Seismic Response Forward Characteristics Of The Deep-seated Volcanic Rock In The East Of Songliao Basin

Because of the deep-buried volcanic rocks, lead to the signal-to-noise ratio of seismic data is very low, and can't provide all the detailed information about the volcanic rock distributions. These issues will badly affect the gas exploration and the prospective appraisement of deep-seated volcanic rocks in the Songliao basin. All the research on identification and prediction for the effective volcanic rock reservoir by using seismic data must focus on forward modeling and combine the inversion modeling technique. So the multi-solution of prediction result has been reduced.In seismic exploration, the forward modeling technique impenetrates in the aspects of data acquisition, data processing and data interpretation. And it is the basis of seismic conversion and the most effective research mean of complicated subsurface geological structure. In this paper, it uses the method of wave equation forward modeling to study the seismic response forward characteristics of the volcanic rock. Before using the forward modeling technique in the study of volcanic rock, it must firstly master the seismic reflectance signatures and the distributing rules of lithofacies about the volcanic rock in the study area, because it is the first step of designing the reasonable forward models.In this paper, according to the practical geological information, seismic data and well logging data of Xingcheng area in Xujiaweizi rift of Songliao basin, simple theoretical and practical volcanic rock models have been built and completed forward modeling with acoustic and elastic wave equation, and the theoretical models have some typical reflectance signatures and the practical models have some practical geological structures all about the deep-seated volcanic rock. The paper comprehensively analyses the seismic response characteristics of volcanic rock and summarizes some propagation rules which have some theoretical sense by combining the result of forward modeling and their snapshots. On the basis of it, conventional treatment, fine pre-stack time migration and pre-stack depth migration process about the modeling result of practical volcanic rock models have been subsequently carried through, and emphasis on analyzing tomography of pre-stack depth migration. It is the core technique of building an accurate velocity-depth model for pre-stack depth migration, because it will directly affect the precision of pre-stack depth migration profile.The research of seismic response forward characteristics of the deep-seated volcanic rock basing on the result of forward modeling and migration is providing solid theory basis for the deep-seated volcanic rock prediction.