Abstract: Sedimentary characteristics of all kinds of fluvial facies are summarized systematically. Combined with practical geology conditions of Early Permian in Jingbei area of Ordos basin and systematic analysis results of depositional characteristics,a new viewpoint is proposed that the depositional system of Early Permian in the area belongs to braided river-shallow water delta deposits,and the sedimentary facies model is built. The difference of depositional characteristics is summarized,and compared with the typical deltaic sedimentary characteristics. It is pointed out that deltaic plain facies is deltaic matrix sand body,which breaks away the traditional thought of the typical delta,and enriched the theories of delta deposition. Provides a new thought for further reservoir prediction and oil and gas exploration.

Key words: Ordos basin, river facies, braided river, depositional model, deltaic plain facies, sand body