Abstract: The Triassic in Hongshanzui-Chepaizi area is one of the important petroleum enrichment zones in northwestern margin of Junggar basin. The favorable exploration play assessment is primarily based on the studies of the sedimentary facies of the Triassic. This study identifies multiple sedimentary facies types in this area through core description and analysis, integrated with the log information and seismic data, including alluvial fan, braided river, delta, lake, etc. The braided river deposit in Lower Karamay formation in Hongshanzui area is the favorable facies belt for lithologic reservoir exploration.

Key words: Hong-Che area, Triassic, sedimentary facies, seismic facies, lithologic reservoir