滦河流域中上游富锶地下水成因类型与形成机制

承德市滦河流域富锶矿泉水资源丰富,成因类型多样,具有典型研究意义。通过水化学图解与多元统计分析、离子比值分析、矿物平衡体系分析,分析富锶地下水形成的地球化学背景,分区阐述富锶地下水水化学特征,探讨富锶地下水的形成机制。结果表明,研究区水化学类型以HCO3-Ca·Mg、HCO3·SO4-Ca、HCO3-Ca、HCO3·SO4-Ca·Mg为主。富锶地下水的形成受地质构造格局和岩浆活动控制,地质建造锶元素丰度影响,水文地球化学条件制约。断裂构造和地层岩性控制着富锶地下水形成分布的总体特征,水文地质条件影响着地下水化学锶元素的地球化学响应机制。地下水锶富集来源为含水介质长石矿物、碳酸盐矿物的风化溶解和阳离子交换吸附作用,矿泉水出露机制分为构造断裂深循环淋溶型、裂隙浅循环淋溶型、补给富集埋藏型3种类型。坝上高原孔隙裂隙水系统富锶地下水形成作用主要受大气降水和溶滤作用控制,滦河中上游裂隙水系统地下水阳离子交换吸附作用强烈,滦河中游孔隙岩溶裂隙水系统地下水化学主要受溶滤作用控制,蒸发浓缩作用和人为活动影响。

Genetic Type and Formation Mechanism of Strontium-rich Groundwater in the Upper and Middle Reaches of Luanhe River Basin

The Luanhe River Basin in Chengde City is rich in strontium-rich groundwater resources with various formation types, and hence it has typical research significance for the study of formation mechanism of mineral water. Based on hydrochemical graphic interpretation, multivariate statistical analysis, ion ratio analysis, and mineral equilibrium system, the authors analyzed the geochemical background for the formation of strontium-rich groundwater, elaborated hydrochemical characteristics of strontium-rich groundwater in various subregions, and investigated the formation mechanism of strontium-rich groundwater. The results show that the main hydrochemical types of groundwater are HCO3-Ca·Mg, HCO3·SO4-Ca, HCO3-Ca and HCO3·SO4-Ca·Mg. The formation of strontium-rich groundwater is controlled by geological structure and magmatic activity, influenced by the abundance of strontium elements in geological formations and restricted by hydrogeochemical conditions. The fracture structure and stratigraphic lithology control the general characteristics of distribution of strontium-rich groundwater, while hydrogeological conditions affect the geochemical response mechanism of the strontium element in groundwater. The strontium in groundwater of Luanhe River Basin mainly comes from weathering dissolution and cation exchange adsorption of feldspar minerals and carbonate minerals. The outcropping mechanism of mineral water can be divided into three types: deep cyclic leaching of tectonic faults, shallow cyclic leaching of fissures and enrichment of recharge type. The hydrochemical formation of Bashang Plateau pore and fissure water subsystem is mainly controlled by atmospheric precipitation and leaching, while the fracture water subsystem of the middle and upper reaches of the Luanhe River is controlled by the cation exchange adsorption. The hydrochemical formation of pore karst fissure water subsystem is mainly controlled by leaching and affected by evaporation and human activities.