沉积物粒度参数内涵及计算方法的解析

Analysis for Sediment Grain Size Parameters of Connotations and Calculation Method

沉积物粒度参数是描述粒度分布特征的基本统计量,包括平均粒径、分选系数(标准偏差)、偏度(偏态)和峰度(尖度)等。全面而深刻地解析了各个粒度参数概念的内涵,指出了认识误区;粒度分析在实践中有广泛的应用;介绍了两种基本的计算方法(图解法和矩算法),近年来前人在计算方法的应用上作出了很多改进,使求解过程变得更省时省力,还提高了可靠性和适用性;众多对比研究表明计算结果的相关性逐渐降低;粒度参数的分级与定性描述可以说明粒度分布的基本特征。

Sediment grain size parameters are the basic statistics that describe the character of particle size distribution, including mean particle size, sorting coefficient （ standard deviation）, skewness and kurtosis. This paper analyzes the connotations of the concept of various grain size parameters comprehensively and profoundly, and points out the misunderstanding;Grain size analysis of the sediments has a wide range of applications in practice, and introduces two basic methods for calculating grain size distribution parameters, namely ,graphic method and moment method;In recent years, our predecessors have made many improvements at the application of calculation method, all of these can save time and effort in the process of solution, and improve the reliability and applicability of the results; Many comparison studies between the results obtained by the two methods have been conducted, and show that correlation gradually decreased;Classification and qualitative description of grain size parameters can be used to illustrate the basic characteristics of grain size distribution.