基于环境同位素法对衡水湖区域地下水循环演化特征研究

Study on the Characteristics of Groundwater Cycle Evolution in Hengshui Lake Area Based on Environmental Isotope Method

衡水湖位于河北省冀枣衡漏斗区西部。为客观认识该地区地下水的循环模式及人类开发利用对地下水循环的影响,根据环境同位素标记性和计时性特点对其进行分析研究,利用D、18O、T环境同位素方法对冀州市衡水湖一带第四系地下水的循环模式进行研究,初步判定该区域地下水补给运移及地下水的循环演化特征。研究结果表明:该区域地下水划分为两种地下水类型,第Ⅰ含水组为"新水",主要接受降水和地表水的补给;第Ⅱ、Ⅲ含水组为"老水",除接受侧向补给外,还接受上层浅水的越流补给;人工超采地下水改变了地下水循环演化特征以及地下水中D、18O、T的同位素组成,增大了地下水遭受污染的风险。

Hengshui Lake is located in the western part of Hebei Province. In order to get the groundwater cycle and the influence of human development and utilization on the groundwater cycle,the study is carried out based on the analysis of environmental isotope labeling and chronological characteristics. The circulation model of Quaternary groundwater in Hengshui Lake area of Jizhou City is studied by D、18O、T environmental isotope method,and the characteristics of groundwater recharge and groundwater circulation are preliminarily determined. The results show that the groundwater is divided into two kinds of types,the first water group is＂new water＂,which mainly receives the precipitation and surface water supply; the second and third water group is ＂old water＂,except for lateral supply,but also accepts the superfluous supply of superficial shallow water. Artificial overdraft groundwater changes the characteristics of groundwater evolution and cycle and the isotopic composition of D,18 O,and T in groundwater,which increases the risk of groundwater contamination.