泾河阶地沉积物粒度分形特征地理学论文.doc

分类号 分类号 学号 密级 Grain Size Fractal Characteristics of Fluvial 题 目 （中、英文） 泾河T1、T2阶地沉积物粒度分形特征 Sediment of Jinghe River 学校代码 作者姓名 指导教师 学科门类 提交论文日期 专业名称 成绩评定 地理学 摘 要 采用Mastersizer2000激光粒度仪对2010年10月采集的泾河彬县段T1、T2河流阶地沉积物共344个样品进行了粒度分析，并对阶地沉积物的粒度分形进行了研究。首先确定沉积物粒度分布具有分形特征的无标度区，然后计算出分维数。在无标度区范围内相关系数R2都大于0.96，沉积物粒度平均分维值第一阶地、第二阶地分别为2.299、2.273，说明沉积物粒度分布具有很好的分形特征。本文把分维值作为一种新的沉积物粒度分析参数，与其传统粒度参数如平均粒径、标准偏差（σ）、偏度（SK）、峰度（KG）进行比较，并分析相关系数，发现在T1阶地中，沉积物粒度的分维值与平均粒径、标准偏差（σ）、偏度（SK）表现为弱的正相关，而峰度（KG）与分维值表现为弱的负相关；在T2阶地中，上层风成沉积物粒度的分维值与平均粒径、标准偏差（σ）、偏度（SK）、峰度（KG）表现为正相关，下层河流沉积物粒度的分维值与平均粒径、峰度（KG）表现为负相关，与标准偏差（σ）、偏度（SK）变现为正相关。 关键词：分形理论；泾河彬县段；阶地沉积物；粒度 Abstract Mastersizer2000 laser Granulometer is used to analyze the 344 terrace sediment samples collected in T1、T2 period in BinXian, Xianyang in October 2010, and the granularity fractal were studied. The fractal scaleless range of grain size distribution is determined and the fractal dimension is calculated. The correlation coefficients R2 of 344 samples of sediments particle size is all more than 0.96. Sediments particle size average fractal value of first terraces is 2.299, and the second is 2.273. This shows that the distribution of sediments particle size has good fractal characteristics. the fractal dimension as a new parameter of street dust size analysis compared with granularity index such as average particle size, standard deviation (σ), slant degrees (SK), the kurtosis (KG). We can find that in T1 terraces, the fractal dimension of sediment granularity exist correlated weak positively with its standard deviation (σ),average particle size and slant degrees (SK), but exist weak negative correlations with its kurtosis (KG) ; in T2 terraces, the fractal dimension of upper Elian sediments granularity exist positive correlations with its standard deviation (σ),average particle size,slant degrees (SK) and the kurtosis (KG) , the lower exist negative correlations with average particle size and kurtosis ,but exi