In 2015 and 2016, groundwater samples were collected in Hanoi to analyse the isotopic composition (δ²H, δ¹⁸O and ³H) and elucidate the relationship between groundwater and surface water, as well as the origin of the groundwater. The values for δ¹⁸O and δ²H indicate that the groundwater originated from evaporated meteoric water and the isotope enrichment is due to the evaporation of shallow groundwater. Evaporation is the primary process affecting stable isotope signatures. Water samples collected from both Holocene and Pleistocene aquifers are more depleted in the heavy isotopes ¹⁸O and ²H than the rainfall in the area. This indicates that part of the groundwater is paleo-groundwater or may be caused by the altitude effect due to recharge at a higher elevation. The results also show the close interaction between two granular aquifers and the Red River. Furthermore, the contribution of modern groundwater could be observed by the appearance of tritium in both aquifers. The presence of tritium indicates that originally tritium-free groundwater from the margins of the basin has been diluted by young water. The results of this study might help managers to evaluate the origin and reserves of groundwater more accurately.

在2015年和2016年，地下水样品收集在河内分析同位素组成（δ ² H，δ ¹⁸ O和³ H）和阐明地下水的原点地下水和地表水之间的关系，以及。对于δ的值¹⁸ O和δ ² ħ指示地下水源自蒸发大气水和同位素浓缩是由于浅层地下水的蒸发。蒸发是影响稳定同位素特征的主要过程。从全新世和更新世含水层收集的水样在¹⁸ O和²的重同位素中消耗更多H比该地区的降雨量多。这表明一部分地下水是古地下水，也可能是由于海拔较高时的补给所引起的海拔效应所致。结果还显示了两个粒状含水层与红河之间的紧密相互作用。此外，通过both在两个含水层中的出现可以观察到现代地下水的贡献。的存在表明来自盆地边缘的最初不含tri的地下水已被年轻水稀释。这项研究的结果可能有助于管理人员更准确地评估地下水的来源和储量。