关键词: 逆时偏移 (RTM), 叠前时间偏移, 碳酸盐岩, 缝洞储层, 塔里木

Abstract: The lower-middle Ordovician carbonate is buried below the depth of 5000 m in the South-West Tarim Basin and the carbonate reservoirs developed in a small scale and are mainly fractured-vuggy type. The accuracy of imaging in this area is difficult. The pre-stack reverse time migration (RTM) established based on the GPU platform is used to improve the accuracy of imaging in fractured-vuggy carbonate reservoirs in this area. Both RTM and tradition pre-stack time migration are implemented to a 3D seismic data processing in an area of 562 km2 in study area. The comparison of the imaging results between reverse time migration and traditional prestack time migration by seismic profiles, coherency attribute and the rate of amplitude change show that the RTM method improves the local imaging in complex tectonic zone, and RTM method is obviously in a dominant position of the description of fractured-vuggy reservoirs and “string beads”.

Key words: reverse time migration(RTM), pre-stack time migration(PSTM), carbonate rock, fractured-vuggy reservoir, Tarim Basin