甘肃省民勤盆地深层淡水及表层咸水成因  

ORIGIN OF DEEP FRESH GROUNDWATER AND SHALLOW SALINE GROUNDWATER IN THE MINQIN BASIN, GANSU PROVINCE

作　　者：李文鹏[1] 

机构地区：[1]地质矿产部环境地质研究所

出　　处：《地质论评》1991年第6期546-554,共9页Geological Review

基　　金：地质矿产部七.五重点科研项目<西北地下水资源评价及合理开发利用>中的专题研究

摘　　要：本文运用环境同位素及水文地球化学分析方法,探讨民勤盆地深层淡水及表层咸水的形成机理,解释地下水上成下淡的盐份分布格局,总结出深层淡水及表层咸水的水文地球化学作用。指出深层淡水仍处于不断矿化之中,但其矿化速度非常缓慢;表层成水中的盐分主要来源于地质历史时期大陆盐化作用累积于地层中的次生可溶盐成份,相对而言含水层本身的矿物蚀变溶解作用可略而不计。The Shiyang River, one of the three large inland drainages in the Hexi Corridor, Gansu Province, originates from the Qilian Mountains and vanishes in the Minqin basin. It is an inland arid basin of the temperate zone. Its aquifer systems consist of Pliocene and Quaternary sediments. Its most obvious hydrogeochemical feature is horizontal and vertical zonation. In the flowing direction of groundwater, the horizontal zonation is as follows: (1) the fresh water zone with a great thickness, (2) the fresh water zone covered with brackish water, and (3) the saline water zone. In this paper, the environmental isotopic (δD and δ^(18)O) and hydrogeochemical analyses are used to study the origin of the deep fresh groundwater and shallow saline groundwater in the area. Most of the salt content in the saline water come from the soluble salts in the strata in the saline groundwater. Soluble salts in the strata are the product of the continuous continental salinization of groundwater in this area and finally resulted in the formation of the distribution pattern of salts: saline water in the upper and fresh water in the lower. The deep fresh groundwater originated in the process of long-continued percolation and desalination of groundwater in-the long geologic history,

关 键 词：水 淡水 咸水 成因 深层 表层 

分 类 号：P578.41[天文地球—矿物学]