The Application Of Pre-stack Seismic Inversion In Reservoir Prediction On H Area In Junggar Basin

Oil and gas reservoir prediction is based on the post-stack inversion methods which used the geological, seismic and logging data comprehensively. The results of the post-stack impedance inversion can achieve the unity of the lateral continuity and the longitudinal resolution, which provide an important basis for the study of the spatial variation and distribution characteristics of the favorable reservoirs.The main post-stack seismic inversion methods include trace integral inversion, original recursive inversion, constrained sparse spike inversion and geostatistical inversion. Trace integral inversion and original recursive inversion, which only applied in the early stage of exploration and development, carry out directly integral or recursive operations from top to bottom in order to obtain relative impedance of stratums. Constrained sparse spike inversion, based on seismic data and restricted by logging data and geological model, obtains absolute impedance of stratums by merging with low frequency and high frequency information so that it can be widely used in the early and middle stage of exploration and development. Combining stochastic simulation algorithms with stochastic inversion method s, geostatistical inversion, which applied in the late stage of exploration and development, can obtain absolute impedance and other attributes of stratums by using the seismic and logging data comprehensively.The application of pre-stack seismic inversion in this thesis mainly aims at the problems of seismic data with poor quality and reservoirs with large buried depth, thin thickness and complex distribution in H area in Junggar Basin. In this study, extension frequency processing is based on the post-stack seismic data, and the geological model is a guide to the interpretation and structure analysis of the target layers. This study takes the seismic attributes and facies analysis of target layers as a reference and standard calibration and sensitivity analysis of the logging data as a key to pre-stack seismic inversion. Post-stack inversion is the core of this thesis, focusing on application and comparison of four post-stack inversion methods which take sand carving and favorable reservoir analysis as a goal.This study predicts that ancient C hepaizi- Mosuowan Paleo-uplift appeared and influenced the deposition in the southeast of H area in the early Sangonghe formation of Jurassic Period. The result of geostatistical inversion that in agreement with logging data in 80% is better to identify the reservoir of target layers where the wave impedance value of the sandstone is less than mudstone. The most favorable reservoir is located in the area near h1 well of southeast of the study area. The two sets of sand bodies are overlapped so that they need to be characterized and described by the results of constrained sparse spike inversion and geostatistical inversion...