Abstract:
The sedimentary characteristics are treated in this study for the Yi'an area along the Wuyur River, Heilongjiang. The sediments herein are represented by the fine-grained meandering stream deposits, which vertically display three-phase depositional cycles, i. e. basal, middle and upper cycles, and may be grouped into three sedimentary subfacies, i. e. channel, overbank and natural levee subfacies, and four sedimentary microfacies, i. e. channel lag deposits, point bar, overbank and backswamp microfacies. The CM patterns based on the granulometric analysis of 30 pieces of samples from individual horizons in the middle cycles display three parts of sediment grain size curves, including the fining-upward graded suspension, homogeneous suspension, and roll suspension, respectively.