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古洪水沉积物的判别在不同流域缺乏统一的判定方法。在总结已有判别方法的基础上,提出一套较为完整的判别方法,即对样品进行野外特征分析、年代分析、重矿物分析、粒度分析,再利用福克公式进行判定,综合比较后确定古洪水沉积,并将其应用于某山区型河流古洪水沉积物判别中。结果表明,古洪水沉积物样品与现代洪水沉积物在重矿物组成上基本一致,但组成的含量比现代沉积物低;粒度分析中的中值粒径、分选系数和偏态系数均较为接近,粒组含量与现代洪水沉积相比较大,古洪水沉积物满足福克公式中河滩沉积物的判别标准。该方法能较好地运用于实际河流中,可为进一步完善古洪水沉积物判别体系提供借鉴。
Discrimination of pale flood sediments lacks a unified method of decision in different watersheds. On the basis of summarizing the existing methods of discrimination, a set of more complete discriminant methods is proposed, that is, the field characteristics analysis, age analysis, heavy mineral analysis, grain size analysis are conducted on the samples, and the Fok formula is used to judge the samples. After comprehensive comparison, Flood deposition, and its application to a mountain river flood sediment discrimination. The results show that the samples of flood flood sediments are similar to modern flood sediments in the composition of heavy minerals, but their composition is lower than that of modern sediments. The median particle size, sorting coefficient and skewness coefficient of particle size analysis are close to each other , The grain size is larger than that of modern flood sediments, and the ancient flood sediments meet the criterion of riverbank sediment in Fokker formula. The method can be applied to practical rivers well and can provide reference for further improving the discriminant system of ancient flood sediments.