荥巩矿区岩溶地下水系统的水文地球化学特征及其指示意义

Characteristics and indication of hydrogeochemisty for the karst groundwater system in the Xinggong coal field

摘要: 本文在分析荥巩矿区水文地质条件的基础上,重点对岩溶地下水系统的水化学特征进行分析。结果表明:岩溶水水化学类型自补给区到排泄区,从单一的HCO3型向复杂的HCO3.SO4型和SO4.HCO3型转变,TDS和Sr2+/Ca2+值均增加。地下水氢氧稳定同位素分析结果表明,本区岩溶地下水主要接受大气降水的入渗补给。根据同位素计算的补给高程推断岩溶水补给范围和划分的流动系统与地面调查结果及水化学研究成果一致:矿区处于区域流动系统排泄带,中寒武统张夏组—中奥陶统灰岩在矿区南部出露的范围接受降水补给,以侧向径流的方式进入矿区充水含水层。

Abstract: Based on a regional hydrogeological survey,the hydrogeochemical characteristics of a karst groundwater system in the Xinggong coal field were analyzed in this paper.The results show that from recharge zones to discharge zones,the hydrochemical type of groundwater changes from HCO3-Ca(Mg) to HCO3.SO4-Ca(Mg) or SO4.HCO3-Ca(Mg) type,TDS and the ratio of Sr2 + to Ca2 + in groundwater increase.Isotopic characteristics indicate that groundwater is mainly recharged from modern precipitation.The recharg.