新疆乌伦古湖表层沉积物元素地球化学行为研究  

Geochemical behavior of elements in surface sediments from Ulungur Lake,Xinjiang

作　　者：王彩红[1] 李瑞博[1] Dembele Blaise 张成君[2] 

机构地区：[1]兰州大学资源环境学院,兰州730000 [2]兰州大学地球科学与矿产资源学院,兰州730000

出　　处：《兰州大学学报（自然科学版）》2015年第5期600-607,612,共9页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金面上项目(41173015);高等学校博士学科点专项科研基金项目(20100211110020)

摘　　要：利用X-荧光法对新疆乌伦古湖26个表层沉积物样品进行常量和微量元素分析,在样品采集时对采样点的水化学参数pH、电导率、盐度等进行测定.结果表明:乌伦古湖表层沉积物主要组成物质中w(CaO)、w(Al_2O_3)、w(Fe_2O_3)、w(MgC))均与w(SiO_2)之间有较好的相关性,w(K_2O)与w(SiO_2)之间的相关性较差(R^2=0.198),w(Na_2O)与w(SiO_2)之间几乎没有相关性(R^2=0.02).大多数微量元素与细粒沉积物有关,湖泊环境对金属元素的迁移和富集起到重要的控制作用.w(Si)/w(Al)可以用来指示封闭湖泊湖面升降变化,w(Si)/w(Al)越低,代表水体越深、水动力越弱的环境;w(Si)/w(Al)越高,代表水动力较强的环境.w(Fe)/w(Mn)对乌伦古湖泊水体深度指示不明显.A total of 26 surface sediment samples from Ulungur Lake in Xinjiang were collected and analyzed for major elements and trace elements with the XRF method.The pH,conductivity and salinity were measured during the sampling process at each sampling site.The results showed that many of the main compositions of the Ulungur Lake surface sediments are significantly correlative with w（SiO_2）,such as w（CaO）,w（Al_2O_3）,w（Fe_2O_3）,w（MgO）,the relationship between w（K_2O） and w（SiO_2） is weak（R^2=0.198）,and almost no relationship exists between w（Na_2O）and w（SiO_2）（R^2=0.02）.Most of the trace elements were relative to the fine-grained sediments,and the lacustrine environment was an important controlling factor to the transformation and concentration of the metal elements.In the closed lakes of arid areas,the proxy of w（Si）/w（A／） refers to the lake level fluctuations：the lower the w（Si）/m（Al）,the deeper a lake with a weaker hydrodynamic force;the higher w（Si）/w（AY）,the stronger the hydrodynamic force.In conclusion,there is no close relationship between w（Fe）/w（Mn） and the depth of Ulungur Lake.

关 键 词：表层沉积物 金属元素 乌伦古湖 新疆 

分 类 号：P595[天文地球—地球化学]