Study And Application Of GPU Pre-stack Migration In Mahu Area

Seismic exploration is one of the most important geophysical methods. Respecting to oil prospecting, seismic exploration is the main method. It consists of acquisition, processing, and interpretation. These flows are connected because the results of the former flow are the inputting data for the next. It is harder for exploration with the exploitation of oil. The requirement of accuracy of processing and interpretation is higher. In the flow of processing data, migration is the technique developed many years ago. With the development of arithmetic of migration, the imaging of subsurface could be described as real formation. However, the contradiction between accuracy and efficiency of migration is always there. The quality of imaging can be improved sacrificing a lot of time for calculation.In this paper, it discussed a new technology, GPU pre-stack migration and its application. It can solve the difficulties of quality and efficiency. GPU pre-stack migration used normally Kirchhoff integral migration method. Works done are as follows: (1) It discussed arithmetic of ray-bending pre-stack Kirchhoff migration. This was an arithmetic that the wave spread from the VTI medium in ray-bending. It was calculated by results of Kirchhoff integral of wave equation, replacing the travel time by the result of time-offset equation in high order. (2)It deduced the factor of amplitude preservation. According to the amplitude variation with incidence, it compensated the amplitude in order to preserve it. In the calculation of this arithmetic, it used anisotropy correction to image the accurate formation. (3)It discussed the anisotropy correction in brief. The correction made out precise migration results. (4) GPU technology could improve the efficient. With the improvement of migration's arithmetic, the problems of complex calculation came out. In order to solve this problem, in this paper, it brought in GPU technique. (5) It used real seismic data processing to prove the dependability of GPU method. (6) Studied the characteristics and results'analysis of GPU pre-stack migration. It analyzed the advantages of this method step by step, studying the consequence to the results. (7) It discussed the application in real seismic data processing. It would compare the new processing data to the old ones in order to illustrate the results and improvement of GPU based pre-stack time migration.GPU pre-stack migration is a method which is good for practice. In this time, pre-stack migration is normal flow. Therefore, precise migration method and high efficient are important to processing. The technique discussing in this paper is reliable.