镜铁山(桦树沟矿区)地下水演化特征及成因分析

Evolution characteristics and genesis of groundwater in Jingtieshan(Huashugou mining area)

研究矿区周围的水文地球化学特征有利于及时发现矿区开采对环境的影响程度,达到有效并及时处理由矿区开采所造成的环境问题的目的。本研究以镜铁山(桦树沟矿区)目标区域为研究对象,运用piper三线图和Gibbs图,辅助该地区降水蒸发线,分析地下水水文地球化学特征,揭示地下水化学成分控制因素。结果表明,该地区地下水化学由SO_(4)·HCO_(3)-Mg·Ca型水逐渐过渡到SO_(4)-Mg型水;区域地下水化学成分主要控制因素为岩石风化作用和蒸发结晶作用,存在阳离子吸附作用;由氢氧同位素数据,利用最小二乘法进行回归拟合,建立研究区域大气降水线方程,反应出研究区域地下水补给来源主要为大气降水,部分为冰川积雪融水。结果表明采矿活动对该区域深层地下水成分并没有造成明显影响,矿山活动对地下水的污染,地下水可通过自净能力处理。研究成果可为该地区预测深部开采的水灾害变化规律提供水文地球化学依据。

The study of the hydrogeochemical characteristics around the mining area is beneficial to discover the impact of mining on the environment in time,and achieve the purpose of effectively and timely dealing with the environmental problems caused by mining.In this study,the target area of Jingtieshan(Huashugoumining area)was used as the research object,and the Piper three-line diagram and Gibbs diagram were used to assist the precipitation evaporation line in this area,analyzed the hydrogeochemical characteristics of groundwater,and revealed the controlling factors of groundwater chemical composition.The results show that the type of groundwater in this area has gradually transitioned from SO_(4)·HCO_(3)-Mg·Ca type to SO_(4)-Mg type;the main controlling factors of regional groundwater chemical composition are rock weathering and evaporation crystal⁃lization,with cation adsorption;Based on the data of hydrogen and oxygen isotope,the equation of atmospheric precipitation line is established by using ordinary least squares regression fitting,which reflects that the groundwater recharge source in the study area is mainly atmospheric precipitation,and part of it is glacier snow melt water.The results show that mining activities have no significant impact on the composition of deep groundwater in this area.Meanwhile,the pollution of groundwater that from mining activities can be treated by self-purification.The research results can provide hydrogeochemical basis for predic⁃ting the changing law of water disasters in deep mining around this area.