天山哈密榆树沟流域夏季洪水期河水水化学特征及其成因

Hydrochemical characteristics and causes of the summer river water in Yushugou basin,Eastern Tianshan Mountains

利用2013年7-8月在哈密榆树沟水文站采集的河水样品,对主要的化学离子、p H值、电导率EC、总可溶性固体TDS进行了系统的分析,阐明了研究区离子的来源及成因.分析结果表明:榆树沟流域夏洪期径流水体呈弱碱性;HCO_3^-、Ca^(2+)分别为最主要的阴、阳离子,Ca^(2+)质量浓度占阳离子总数的69.45%,HCO_3^-质量浓度占阴离子总数的84.18%;水化学类型为HCO_3^--Ca^(2+);径流中所含的水化学物质一定程度上受水量的稀释作用控制;通过Gibbs图、阴阳离子三角图示法以及主要离子比值法的综合分析得出,水化学离子主要来源于H_2CO_3风化碳酸盐岩,同时还伴有少量的H_2SO_4风化碳酸盐岩,岩石风化主要以方解石矿物的溶解作用为主.

Using the water samples collected in Yushugou River basin during July-August, 2013, the main chemical ions, pH value, electrical conductivity and total dissolved solid were analyzed systematically, and the sources and causes of the ions were discussed. The analysis results show that the river water was weak alkaline. The main anion and cation were HCO; and Ca2 ＋. The concentration of Ca2 ~ accounted for 69.45% in cations, and that of HCO3- accounted for 84.18% in anions. Thus, hydrochemical type of the river water was H2CO3-Ca2~ During the flood period, water chemicals contained in river water were partly effected by water dilution. Based on the comprehensive analysis by Gibbs Figure, triangular diagrams of anions and cations and main ion ratio method, it was revealed that the main source of major ion in water was rock weathering. Carbonate rock weathering was mainly controlled by weathering H2 CO3 rock accompanied by a small amount of H2 SO4 at the same time. Rock weathering were mainly composed of calcite mineral dissolution.