Abstract：Based on description of outcrop section and cores，drilling well and logging and seismic data，the types of sedimentary facies and their characteristics of the Paleogene and Neogene were studied in the north margin of Qaidam Basin.The research showed that alluvial fan，fan delta，braided fluvial，braided fluvial delta and lacustrine facies were developed in the Paleogene and Neogene.The sedimentary spatial-temporal distribution was affected by the structural framework of basin base，the growth thrust faults of altun slope，the thrust fault in the north margin and palaeo-high land，bringing about the sedimentary system with diversity.By the effect of thrust faults and palaeo-high land，alluvial fan，fan delta and lacustrine facies were present in Lenghu-area，and alluvial fan-braid braided river delta were present in Mahai-Nanbaxian area.The systematic analysis about palaeogeographic evolution was achieved based on the sedimentary facies analysis，and more reliable geological information was provided for the further exploration.
Li Fengjie,Meng Lina,Fang Chaogang et al. Palaeogeographic evolution of the Paleogene and Neogene in north margin of Qaidam Basin[J]. JOPC, 2012, 14(5): 596-606.
