Application Of The Modeling Techniques Of Migration Velocity Based On Grid Tomography In The Yue Man Area

Along with the development of exploration,pre-stack depth migration has gradually become a significant method for the large oil and gas fields.However,this method requires higher accuracy of the velocity model in the process.If the velocity is not accurate,it will impact on the quality of the final pre-stack depth migration image.Accordingly,the accuracy of the velocity model plays a vital role in the pre-stack depth migration.This paper is mainly to improve the quality and fidelity of pre-stack depth migration seismic data and reduce the error of the layer,and increase the success rate of drilling.In this paper,the overall reflection layer of the research area is relatively complete;the overall SNR of the data is really high.But the SNA of main target layer is very low;the overlying Permian igneous rock has a great influence on it,the velocity of the igneous rocks change severely in the transverse.In order to solve the above situation,in this paper,the current mainstream modeling methods are researched firstly,and their merits and flaws are compared.Then the basic principle of grid tomography has introduced,which is further understanding and cognition of the modeling technology of grid tomography.The last is the application of the grid tomography migration velocity modeling technology in Yue Man area.We found that the modeling method can counter close to the velocity of the real formation and level all the common reflection point gather,and the residual delay of velocity is close to zero,the quality of the final migration section is obviously improved.This fully proves that the velocity modeling technology based on the grid tomography can effectively solve the complex geological structure of oil and gas exploration.