Grain Size Features and Genesis of the Qingshan “Sand-dune” in Wuhan

Key words: 
• Qingshan “sand-dune” /
• grain-size /
• eolian origin

Abstract: Based on the grain-size analyses of representative section of Qingshan “sand-dune” in wuhan, the causes of “sand-dunes” is discussed in this paper. The results show as follows: Qingshan “sand-dune” mainly consists of sand with the average content over 59%, while 23% coarse silt and 11% fine silt approximately, only little in clay content. The characteristics of grain size parameters is same as typical sand dune, frequency distribution curves with two crests, and probability cumulative curves with a pattern of two segments, partly three, and high content of saltation load, closely resemble that of eolian sediments, C-M chart and statistical indices of grain size distribution different with fluvial sediment obviously, the discriminant analysis result is mingled with plus-minus. With a brief calculation, “sand-dunes” are fluvial sediment which outcropped in the last glaciation blown and conveyed by wind, then deposit in the south bank of Yangtze River.