BGP Dagang Branch of Geophysical Research Institute, CNPC, Tianjin 300280, China

Based on the analysis of seismic reflections and AVO response,the authors systematically studied the gas reservoir characteristics of the 1st member of Shanxi Formation of Su20 block in Sulige gas field using the supervised SPR and CM hydrocarbon prediction. It is believed that the gas reservoirs of the 1st member of Shanxi Formation is widely distributed in the study area, and mainly controlled by lithology. On seismic reflection profiles, the gas reservoirs show high amplitude and middle-low frequency, or low amplitude and middle-low frequency. AVO response on near angle stack is stronger than that on the far angle stacks. In addition to the known gas-rich region in the middle-west and southeast of Su20 block, there exist some lithologic gas reservoirs in the north and southwest of the study area, which are the important targets of future exploration and development.