Abstract: Well S112-2 drilled in the south of Tahe Oilfield found commercial oil accumulation in the Silurian Kepingtage Formation. Based on the crops, logging and seismic data, the Kepingtage Formation is divided into two third -sequences. The Silurian in the south of Tahe Oilfield develops coastal-offshore sediments with barriers.Accordingly, the Lower Member of the Kepingtage Formation corresponds to lower land systems tracts of SQ1（SQ1-LST）, which mainly develops middle tidal flat（mixed flat）sediments; the Middle Member of the Kepingtage Formation corresponds to transgressive systems tracts of SQ1（SQ1-TST）, forming the offshore continental shelf sediments; the Upper Member of the Kepingtage Formation corresponds to the lower land systems tracts of SQ2（SQ2-LST）, which forms primarily the lower tidal flat（sand flat）sediments. In the south of Tahe Oilfield, the study also compiles sedimentary subfacies distribution maps of the above three system tracts of the Silurian, which provides the basis for further reservoir prediction in the area.

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