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对撒哈拉沙漠东北部苏丹境内东西方向３６个样品粒度分析结果表明：其粒度组成可分为１０种不同的类型；粒度参数具以下特征值：ＭＺ＝１．３４～２．４３；标准偏差δＩ＝０．５１～１．４３；偏度ＳＫＩ有正有负，变化于－０．３～０．４７；峰态ＫＧ＝０．６６～１．０４。同时显示，绝大多数样品的频率曲线为多峰态，具有典型河流沙的粒度特征；不同样品及粒度分布形式在地域上无明显规律性。分析结果说明非洲撒哈拉沙漠东北部沙漠砂的形成与河流作用有关。
The results of particle size analysis of 36 samples in the east-west direction in northeastern sub-Saharan Africa show that the particle size distribution can be divided into 10 different types; the particle size parameters have the following characteristic values: MZ = 1.34-2.43; standard deviation δI = 0.51 ~ 1.43; skewness SKI positive and negative changes in the -0.3 ~ 0.47; kurtosis KG = 0.66 ~ 1.04. At the same time, the frequency curves of most samples are multi-peaked, showing the grain size characteristics of typical river sediment. The distribution of different samples and size distribution has no obvious regularity in the area. The analysis shows that the formation of desert sand in the northeastern Sahara of Africa is related to the role of the river.