Through the investigation for eleven profiles in the Dingxing point bar, the vertically depositional sections can be divided into two types,one is dominated by the large trough cross-bedding,the another is dominated by opposite inclined bedding,and this paper also discusses the developing process of the former.According to the geomorphological location,texture and structures of the deposits,the point bar is divided into six sub-facies:channel lag deposits,small shoal,flute bars,flood fill deposits between two flute bars,chute deposits and mud bodies on the outside of fIute bar.Finally,the paper deals with the origin of the two kinds of interesting bedding-distorted stratification and opposite inclined bedding.
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