Characteristics of sedimentary facies and evolution in sequence stratigraphic framework of the Upper Triassic Yanchang Formation in southern Ordos Basin
Chen Fei1,2, Hu Guangyi1, Sun Lichun1, Fan Tailiang3, Gao Zhiqian3, Yu Xitong4, Pang Zhenglian5, Li Rangbin1
1 CNOOC Research Center,Beijing 100027 2 Post-doctoral Research Station,China University of Petroleum(Beijing),Beijing 102249 3 China University of Geosciences(Beijing),Beijing 100083 4 Tianjin Branch of CNOOC Limited,Tianjin 300452 5 Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083
Abstract:According to the theory and approach of high resolution sequence stratigraphy and sedimentology,combining with core,drilling well,well-logging and seisimic data,detailed studies has been carried out on the Upper Triassic Yanchang Formation of the southern Ordos Basin.Totally five sequence boundaries,four 3rd and eleven 4th sequences were identified and the sequence stratigraphy framework was built up.Four types of sedimentary facies were developed in this area,including meandering fluvial delta,braided fluvial delta,lacustrine and deep-water gravity flow facies.The characteristic distribution of sedimentary facies in sequence stratigraphic framework was illustrated,and the law of evolution and distribution of sedimentary facies in sequence stratigraphic framework was established and the distribution of sandbodies in sequence stratigraphy was generalized.Taking the constantly deepening understanding of the sedimentary facies as the guidance,great breakthrough has been made in the petroleum exploration of the Yanchang Formation in the Ordos Basin.
Chen Fei,Hu Guangyi,Sun Lichun et al. Characteristics of sedimentary facies and evolution in sequence stratigraphic framework of the Upper Triassic Yanchang Formation in southern Ordos Basin[J]. JOPC, 2012, 14(3): 321-330.