Kirchhoff pre-stack time migration of complex surface data on CPU+GPU
Ma Zhaogui1,2, Zhao Gai-shan1, Wu Gangshan2, Xu Zilong1, Duan Wenchao1, Wang Haib1
1. Geophysical Research Institute, SINOPEC, Nanjing, Jiangsu 210014, China; 2. National Key Laboratory for Novel Software Technology, Nanjing University, Nanjing, Jiangsu 210093, China
Abstract：This paper discusses surface topography Kirchhoff pre-stack time migration of data in tight topography areas on CPU+GPU platform and its efficiency. We first analyze anti-aliasing, bending ray travel time calculation with high order, travel time corrections from the true surface, and the parallel framework of the original algorithms. Then we design a new parallel framework which is suitable to CPU+GPU platform. Offset domain calculations are conducted by multi-process parallelism, and seismic data I/O are carried out by asynchronous parallelism. Based on multi-thread parallelism with CPU and massively threads parallelism with CUDA in imaging domain, the original CPU algorithms are transplanted and optimized. Test results with large scale seismic data show that Kirchhoff pre-stack time migration calculations can be carried out much faster on the multi-level parallel framework based on CPU+GPU platform.
