北京平原周边基岩水和地表水的水化学及同位素分析

A study of hydrochemistry and stable isotopic in bedrock-well water and surface water near Beijing Plain

利用北京市平原周边基岩水和地表水样品中的T值和Cl-含量对大气降水的输入进行了定量估计。研究结果表明全部样品均为热核爆炸后的补给输入,Cl-≤6.8mg/L的水样为北京平原区近工业化前(距今约150～200a)的输入值,6.8～20mg/L为北京地区区域大气轻微污染条件下的Cl-输入值。通过对2H和18O同位素的关系研究,认为北京平原区的高程效应远比大陆效应显著,并且提供了一张北京平原区地下水研究用的比对样板。

Tritium values and Cl^-concentrations from groundwater in the bedrock aquifers and surface water are used to estimate quantitatively the input from precipitation in Beijing. The results indicate that the whole sampling recharge input is after the nucleus explosion, the Cl^- concentrations in the Beijing plain region before near industrialization is about 6.Smg/L, the regional input value ranges from 6.8 to 20 mg/L. The relationship between ^2H and ^18O suggests that in the Beijing Plain the altitude effect is more notability than the continental effect, and a contrast model for groundwater research in Beijing Plain is also provided.