云南勐野井钾盐矿床中Br和I的影响因素及意义  

Influence Factors and Significances of Br and I in the Mengyejing Potash Deposit,Yunnan,China

作　　者：孙淑蕊[1,2] 李明慧[1] 颜茂都[1,3] 刘晓明[1] 方小敏[1,3] 

机构地区：[1]中国科学院青藏高原研究所,北京100101 [2]中国科学院大学,北京100049 [3]中国科学院青藏高原卓越中心,北京100101

出　　处：《矿物岩石地球化学通报》2016年第2期360-367,共8页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家重点基础研究发展计划项目(2013CB956400);中科院战略性先导科技专项B(XDB03020400);国家自然科学基金项目(41271100;41321061)

摘　　要：为探究盐类矿床中Br和I元素的影响因素及其对钾盐矿床成因的指示意义,采集思茅盆地勐野井的石盐、钾盐样品,采用X射线衍射方法分析了其盐类矿物组成,用ICP-OES和离子色谱仪测试了阳离子(K^+、Ca^(2+)、Na^+、Mg^(2+))和阴离子(Cl^-、Br^-、I^-、SO_4^(2-))组成。结果显示,样品的Br含量为89.08×10^(-6)~555.45×10^(-6),高于海水含量,Br×10~3/Cl的质量比值为0.13~0.86,Br的主要影响因素是溶液的主要成分(SO_4^(2-),K^+,Ca^(2+)和Mg^(2+))和蒸发作用;I含量为0.07×10^(-6)~0.27×10^(-6),I×10~6/Cl的摩尔比值为0.03~0.11,略高于海水值,I含量随I×10~6/Cl摩尔比值的增加呈上升趋势,说明蒸发作用是影响卤水I含量的因素之一。但Br和I呈负相关,表明有机质的含量是I含量的主要影响因素,蒸发作用可能是次要影响因素,I和I×10~6/Cl摩尔比值可能是判断海陆相的潜在指标之一。In order to identify influence factors of Br and I of salt minerals and their implications to the metallogenesis of the potash deposit, salt samples collected from the Mengyejing potash deposit in Simao basin, Yunnan Province, have been examined by using X-ray diffraction for their textures, and ICP-OES and ion chromatograph ICS-900 for contents of their cations（K＋, Ca2_, Na＋and Mg2_） and anions（ Cl-, Br-, I-, and SO4^2-）, respectively. Results show that Br contents of samples vary from 89.08 ppm to 555.45 ppm which are higher than that of the sea water. Molar Br/Cl values of samples vary from 0. 13×10^-3 to 0. 86×10^3. Contents of Br are mainly affected by compositions of the solution（ SO4^2- , K＋ , Ca2＋ and Mg2＋） and the solution evaporation. I contents vary from 0.07^-6 to 0.27×10^-6 which are slightly higher than that of the sea water. I/Cl molar ratios vary from 0.03^-6 to 0. 1 1 ^-6. The positive relationship between I contents and I/C1 rati- os suggest that the evaporation is one of factors on the I content of the brine. However, the negative correlation between Br and I contents suggest that the content of organic matters may played more important role than the evaporation on the con- tent of I. I contents and I/Cl molar ratios of samples may be appliedto identify their continental or marine origins.

关 键 词：勐野井 BR Br/Cl I I/Cl 

分 类 号：P619.211[天文地球—矿床学]