人类活动影响下娘子关岩溶水系统地球化学演化  

Geochemical evolution of the Niangziguan karst water system under the impact of human activities

作　　者：王焰新[1] 高旭波[1] 

机构地区：[1]中国地质大学环境学院及教育部生物地质环境地质重点实验室,湖北武汉430074

出　　处：《中国岩溶》2009年第2期103-112,共10页Carsologica Sinica

基　　金：国家杰出青年科学基金(40425001);国家自然科学基金重点项目(No.40830748)

摘　　要：娘子关泉是我国北方最大的岩溶泉之一,也是阳泉市工农业生产和人民生活的重要供水水源。地下水地球化学演化分析表明,在地下水由补给区向排泄区运移过程中,除固有的水岩相互作用外,由于受采矿活动和地表水入渗补给的影响,岩溶水由低离子含量的HCO3-SO4或HCO3型水逐渐成为SO4型、SO4-HCO3型和SO4-HCO3-Cl型水。在泉群集中排泄区,区域流动系统与局部流动系统的地下水发生混合作用,最终形成了水质相对良好的HCO3-SO4型或SO4-HCO3型岩溶泉水。在此过程中,地下水对方解石和白云石也由最初的溶解作用演变为沉淀再结晶。尽管石膏呈持续溶解现象,但在采煤活动严重影响区域,石膏的沉淀也可能出现。地球化学模拟表明,在岩溶含水层中,地下水首先以方解石(白云石)的溶解为主;随着石膏溶解数量的增加,方解石(白云石)的溶解开始受到抑制,进而发生沉淀,石膏的溶解成为控制地下水水化学的主导过程。当矿坑水混入时,地下水相对石膏过饱和,地下水对碳酸盐岩含水介质的溶蚀能力得到增强。随着水岩反应的演进,铁氢氧化物大量沉淀,通过共沉淀和吸附作用去除了地下水中的重金属类污染物。As the largest karst spring in north China, the Niangziguan spring is the most important source of water for Yangquan city in Shanxi province. Affected by the water-rock interaction and recharge by the leakage of coal mining waste water and surface water, the hydro-chemical type of the karst water turns gradually from the HCO3-SO4 or HCO3 type into the SO4, SO4-HCO3 or SO4-HCO3-C1 one from recharge area to discharge area. In the centralized discharge area of the spring group, good quality HCO3-SO4or SO4-HCO3 type water is formed by the mixing of groundwater from regional and local water system. During the transport of groundwater, over-saturation of calcite and dolomite resulted in precipitation and recrystalization. The dissolution of gypsum prevails except for areas where the groundwater is affected by coal mining and gypsum precipitation may occur. In the karst aquifer, groundwater quality is controlled at the beginning by calcite （dolomite） dissolution and then by gypsum dissolution once calcite （dolomite） dissolution is restrained. Gypsum in groundwater may precipitate and the carbonate dissolution capacity of groundwater is enhanced with leakage of coal mine drainage. Iron hydroxide in the groundwater precipitates with the evolution of water-rock interaction and heavy metals in the groundwater are removed via co-precipitation and adsorption by iron hydroxide.

关 键 词：岩溶地下水 地球化学演化 人类活动 娘子关 

分 类 号：P641.33[天文地球—地质矿产勘探]