Abstract: A correct understanding of the shape and scale of meandering river point bar sand bodies is of great significance to the understanding of interwell sand body connectivity,fluid migration path analysis and efficient and accurate tapping of remaining oil. Taking the modern Baihe river in the Yellow River source area as an example, ArcGIS software was used to vectorize the 31 typical point bar sand bodies in the Baihe satellite image,and the basic measurement data table of the parameters of point bar sand body scale was established. The typical point bar meandering sections were selected for characterization through slope division,and the quantitative relationship between the scale of the point bar sand bodies and the width of the river channel was discussed on the basis of curvature division. The results show that the larger the slope,the smaller the river width and the smaller the curvature. There is a positive correlation among point bar length,point bar width and river channel width,and the correlation is different under different curvatures. When the curvature k is less than 2,the correlation coefficient between point bar length and river channel width is 0.790,the correlation coefficient between point bar width and point par length is 0.812,and the correlation coefficient between point bar width and river channel width is 0.414. When k is 2.0-2.5,the correlation coefficient between point bar length and river channel width is 0.709,the correlation coefficient between point bar width and point bar length is 0.883,and the correlation coefficient between point bar width and river channel width is 0.841. The research results can be used for reference to the quantitative characterization of meandering river reservoirs.

Key words: meandering river, point bar, quantitative characterization, curvature, ArcGIS, slope, modern deposition