The gravels in red clay and river sediments of Hengyang basin were characterized in their size, sphericity, flattening and surface features in this study with the characteristics of gravels in river red clay sediments compared each other. Results showed that The gravels in red clay sediments were significantly different from those in river sediments in the probability of occurrence of sub--rounded, impact craters and hypo--edge angle, The difference between gravels in red clay and river sediments in- cluded also in b and c axis values. The sphericity value of gravels in river sediment was bett...
