南太行山前冲积平原潜水水化学特征及控制因素分析

Analysis on hydrochemical characteristics of groundwater in alluvial plain of southern Taihang Mountains

南太行山前冲积平原地下水分带性明显,区域内人类活动频繁导致地下水化学组分来源复杂。为明确位于南太行山前冲积平原区水文地球化学特征及影响因素,获取了潜水水样109组以及44组氢氧同位素样品。通过水化学特征分析、离子比例系数法及水文地球化学模拟等手段,明确潜水在南太行山前冲积平原地区水化学类型表现为HCO_(3)·Cl·SO_(4)-Ca·Na及Cl·SO_(4)·HCO_(3)-Ca·Na,浅层地下水位降落漏斗区转变为HCO_(3)·Cl·SO_(4)-Ca·Na;研究区内主要受控因素有水岩作用、蒸发浓缩作用、离子交换作用以及人类活动的影响。区内沿地下水流向,平原区内方解石、白云石及石膏等矿物均溶解,浅层漏斗区内方解石过饱和沉淀,白云石和石膏溶解程度增强,同时浅层漏斗区具有强烈的Ca^(2+)与Na^(+)的阳离子交换作用。平原区主要受控因素为蒸发浓缩作用,浅层漏斗区内受控因素主要以水岩作用、阳离子交换作用为主,其中部分地区受控于工业化活动影响。该研究对南太行山前冲积平原区域潜水资源合理性利用具有重要意义。

The groundwater zones in alluvial plain of southern Taihang Mountains is obvious,and the frequent human activities in the area lead to complex sources of groundwater chemical components.To clarify the hydrogeochemical characteristics of the groundwater in alluvial plain area of the southern Taihang Mountains and influencing factors,109 sets of groundwater samples and 44 sets of hydrogen and oxygen isotope samples were obtained.By means of water chemistry characterization,ion proportionality coefficient method and hydrogeochemical simulation,it is clear that the groundwater chemistry type in alluvial plain area of the southern Taihang Mountains is expressed as HCO_(3)·Cl·SO_(4)-Ca·Na and Cl·SO_(4)·HCO_(3)-Ca·Na,and the shallow groundwater table landing funnel area is transformed into HCO_(3)·Cl·SO_(4)-Ca·Na.The main controlling factors in the study area are water-rock action,evaporation concentration,ion exchange and the influence of human activities.Along the groundwater flow direction in the zone,calcite,dolomite and gypsum minerals are dissolved in the plain zone,and calcite supersaturates and precipitates in the shallow funnel zone,and dolomite and gypsum dissolve to an enhanced degree,while the shallow funnel zone has strong cation exchange between Ca^(2+)and Na^(+).The main controlling factors in the plain area are evaporation and concentration,and the controlling factors in the shallow funnel area are mainly water-rock action and cation exchange,some of which are controlled by the influence of industrialization activities.This study is of great significance to the rational use of groundwater resources in the alluvial plain area of southern Taihang Mountains.