河北省唐山市陡河流域地下水年龄评价

Groundwater Age Assessment of Dou River Basin in Tangshan City,Hebei Provence

利用环境同位素研究地下水年龄对区域地下水资源评价提供可靠依据。本文以陡河流域为例，通过采集大量地下水中的环境同位素样品，测试水中氚、CFCs和14C含量，分别计算地下水年龄，评价地下水的可更新能力。研究结果表明：Q4含水层受井孔利用情况平均滞留时间存在显著差异；Q3含水层地下水年龄最广，从70年以前的老水到新水不等；Q2含水层主要为生活供水和工业开采层，远离河岸带地下水年龄10~70年；远离河岸带Q1含水层地下水为冷湿气候下补给；灌区地下水浇灌过程中与大气接触发生空气-水平衡，使得CFCs不适合于灌区地下水年龄计算。

Groundwater age assessment with environmental isotopes could useful for local groundwater resources evaluation and management. Dou River Basin has been selected as the typical study area, amount of groundwater samples have been tested with 3H, CFCs and 14C, groundwater ages have been calculated. The results show that, groundwater ages changes obviously in Q4 aquifer with the impact of human activities;groundwater ages varied most widely in Q3, and the age distributed from old water 70 year ago to new water; as the main development aquifer, Q2 aquifer has the groundwater ages from 10 to 70 years;groundwater in Q1 aquifer recharged with pre-cipitation from cold and wet climate; because of the air-water equilibrium during the irrigation process, CFCs method is not suitable to calculate the groundwater age in irrigation area.