云南腾冲地区地热流体的地球化学特征

对云南热海和瑞滇地区地热流体的地球化学特征进行了分析和探讨,并据此评估了地热流体对环境的影响.结果显示,研究区的碱性热泉中K、Na、F、Cl、SiO_2的含量高,而只存在于热海地区的酸性热泉中SO_4~(2-)、Mn、Fe的含量高.热泉中As、Sb的含量范围分别在43.6～687μg/L和0.38～23.8 μg/L之间.热泉中以As(Ⅲ)为主,占了总砷的91%.地热流体中的As、Sb一部分被固定在泉华中,而另一部分则释放到了环境中,从而进入地下水和下游的田地中,对当地居民的健康造成威胁.

Geochemical characteristics of geothermal fluid in Tengchong Area,Yunnan Province, China

The geochemical characteristics of the hot spring waters in the Rehai and Ruidian geothermal fields, Teng-chong County, Yunnan Province, China, were described and their possible environmental impact was assessed. The results show that the alkaline spring waters contain high levels of K, Na, F, Cl, and SiO_2, whereas the only acidic spring water in Rehai geothermal field contains high levels of SO_4~(2-), Mn and Fe. As and Sb in the spring waters are in the ranges of 43. 6-687 μg/L and 0. 38-23. 8 μg/L, respectively. As (Ⅲ) occur s in most spring waters, and thefraction of As( Ⅲ) is up to 91% of total As. Fractions of geothermal As and Sb are trapped in the sinter deposits while most of them enter the environment The diffusion of As and Sb into groundwater and downstreams in crop fields constitutes a threat to the health of the local population.