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The He-8 member of Middle Permian in the eastern Sulige area of Ordos Basin is the main gas producing bed, and is of great significance to clarify the sedimentary facies characteristics for guiding the natural gas exploration. There are similar provenance systems and sedimentary environments between the eastern Sulige area and Fugu section in the northeastern margin of Ordos Basin. By measuring Fugu section combined with facies markers such as color, petrology, trace elements and lithofacies characteristics, the sedimentary facies of He-8 member was divided accurately, and the sedimentary characteristics were clarified to make up for the lack of outcrop sedimentary facies support in most of the previous study of He-8 member in the eastern Sulige area, which was limited to drilling and earthquake. The results show that the grayish green and yellowish green coarse to medium grained lithic sandstone are the main ones in He-8 member of Fugu section, and the structure maturity is medium to low; the trace element V/(V+Ni)ratio indicates that the depositional period of He-8 member is a transitional environment of oxidation-weak reduction; there are 12 types of lithofacies, among which Gm, St, Sp, Sh are typical lithofacies in fluvial sediments, and two different vertical sedimentary sequences are formed by different lithofacies combinations; He-8 lower member to He-8 upper-2 member is braided river deposit, and He-8 upper-1 member is meandering river deposit; the vertical sedimentary sequence of braided rivers consists of six types of microfacies, including stranded sediment(Gm-Gst-Gsp), braided river bar(Gst-Sq-Sp-St-Gm-St), channel filling(Gm-St-Sh-M), abandoned channel(Sh-Fr-Mh-Sh-Fr-Mh), overbank deposits(Sh-Fr-Mh-Fr-Mh)and flood plain(M-Mh-Mc-Mh-M), and forms a sequence of normal sequence deposits with a binary structure unobviously; the vertical sedimentary sequence of meandering river consists of three types of microfacies, including stranded sediment(Gm), side beaches(Sp-St-Sm-Sp-St-Sh)and flood land(M-Mh-Mc(Fr)-Mh-M), and constitutes a typical binary structure sedimentary sequence. [ABSTRACT FROM AUTHOR]