武汉青山“砂山”粒度特征及其成因指示  

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

作　　者：杨勇[1] 李长安[2] 胡思辉[3] 霍炬[1] 孙浩[1] 王秋良[2] 

机构地区：[1]中国地质大学研究生院,武汉430074 [2]中国地质大学地球科学学院,武汉430074 [3]信阳师范学院文学院,河南信阳464000

出　　处：《沉积学报》2008年第3期487-493,共7页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(批准号:40372079);中国地质大学(武汉)研究生学术探索与创新基金共同资助

摘　　要：根据代表性的武汉青山"砂山"的粒度分析探讨"砂山"的成因。结果表明:剖面砂颗粒含量较高,平均达59%,粗粉砂约23%,细粉砂约11%,黏土含量少。粒度参数特征与典型沙丘砂一致,频率分布曲线为双峰,概率累积曲线为两段式,部分层位三段式,跃移质含量高,显示风积成因,C—M图及结构参数散点图与河流沉积物差别明显,判别分析结果正负夹杂。综合看来,"砂山"是末次冰期时出露的河流沉积物经风力吹扬、搬运,在长江南岸堆积而成。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 the 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.

关 键 词：青山“砂山” 粒度 风成 

分 类 号：P512.2[天文地球—地质学]