图解法和矩值法计算西台吉乃尔盐湖沉积物粒度参数的差异

Differences of Particle Parameters Calculated by Graphic and Moment Methods in Sediments at the West Taijinar Salt Lake Region 

中文关键词:  柴达木盆地  西台吉乃尔盐湖  粒度

英文关键词::Qaidam basin  West Taijinar salt lake  Grain size

中文摘要:

      柴达木盆地西部的西台吉乃尔盐湖既是研究成盐演化的典型湖泊,也是一个重要的盐湖资源产地。盐湖沉积物的粒度组成记录了湖泊沉积环境和动力条件的变化,对于理解盐湖的形成演化具有指示意义。目前有关盐湖沉积物粒度参数(平均粒径、标准偏差、偏度和峰度)计算的报道较少。采用Beckman Coulter LS 13320激光粒度仪测定了西台吉乃尔盐湖沉积剖面(XT剖面,240 cm厚)121个样品的粒度组成,并对图解法和矩值法计算出来的粒度参数进行了比较。分析结果表明,1)图解法和矩值法得出的平均粒径和标准偏差非常一致,二者可以相互替代；2)两种方法得出的偏度和峰度存在显著差别,二者不可替代；3)矩值法计算整体考虑了样品粒度的频率分布特征,得到的粒度参数比图解法更全面。

英文摘要:

      :West Taijinar salt lake is an important production base of salt lake resources. Grain size of sediments in salt lakes can reflect the depositional environments and dynamic changes in lake conditions, which is of significance for understanding the formation and evolution of salt lake. Currently, report about particle parameters (mean grain size, standard deviation, skewness and kurtosis) in salt lake sediment is still few. Based on the Beckman Coulter LS 13320 laser particle sizer, the grain sizes of 121 samples of the sediments from the West Taijinar salt lake region (XT section, 240 cm thick) have been tested. The particle parameters of the sediments in XT section have been compared by methods of graphical and moment methods. The results show that:(1) For the sediments in the XT section, the mean grain size and the standard deviation calculated by graphical and moment methods are very consistent, and both can substitute for each other; (2)There are significant differences in skewness and kurtosis derived from the two methods, and both cannot be replaced for each other; (3) Due to the moment method considering the whole frequency distribution of the grain size in a sample, the particle parameters derived from the moment method are more comprehensive than those obtained by the graphical method.