Abstract The geochemical evolution of groundwater of the Puebla aquifer was investigated using chemistry and isotopic data with special emphasis on the geochemistry of Boron to decipher the natural and anthropogenic sources. This study measured 70 groundwater samples that are potentially impacted by the urban and rural anthropic, volcanic and glaciation activities. Based on the distribution of anions and cations water samples were classified into three groups using Piper Diagram. Group1 showed to have high HCO3 than SO4, Group 3 high SO4 than HCO3 and Group 2 revealed intermediate composition. Radiometric studies show the presence of Pleistocene groundwater; however, there was no definite relationship between the radiometric dates to the groups except that enrichment in δD and δ13C values were noted with respect to age. Average Boron concentrations in some wells were observed to be higher (>5000 μg/L) than that of the permissible limit for human consumption. Results also indicated that the sources of Boron were more natural than anthropogenic that comprised the local geological conditions, volcanic activity and hydrothermal processes. The study also validated that the groundwater wells from the southwestern part of the study area are suitable for extraction of groundwater, considering its quality and residence time; whereas, in the wells located in the central-eastern zone of the metropolitan area, it is recommended that groundwater exploitation must be gradually reduced.

中文翻译：

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墨西哥中南部普埃布拉河谷受城市和火山活动影响的地下水地球化学演化和硼来源

摘要 利用化学和同位素数据研究了普埃布拉含水层地下水的地球化学演化，特别强调硼的地球化学，以破译自然和人为来源。这项研究测量了 70 个可能受城市和农村人为、火山和冰川活动影响的地下水样本。根据阴离子和阳离子的分布，使用派珀图将水样分为三组。第 1 组 HCO3 比 SO4 高，第 3 组 SO4 比 HCO3 高，第 2 组显示中间成分。放射性研究表明存在更新世地下水；然而，除了 δD 和 δ13C 值的富集与年龄有关之外，辐射测量日期与各组之间没有明确的关系。观察到一些井中的平均硼浓度高于（> 5000 μg/L）人类消耗的允许限值。结果还表明，硼的来源比人为来源更自然，包括当地的地质条件、火山活动和热液过程。研究还验证了研究区西南部的地下水井，考虑到地下水的质量和滞留时间，适合抽取地下水；而位于大都市区中东部地区的水井，建议逐步减少地下水开采。结果还表明，硼的来源比人为来源更自然，包括当地的地质条件、火山活动和热液过程。研究还验证了研究区西南部的地下水井，考虑到地下水的质量和滞留时间，适合抽取地下水；而位于大都市区中东部地区的水井，建议逐步减少地下水开采。结果还表明，硼的来源比人为来源更自然，包括当地的地质条件、火山活动和热液过程。研究还验证了研究区西南部的地下水井，考虑到地下水的质量和滞留时间，适合抽取地下水；而位于大都市区中东部地区的水井，建议逐步减少地下水开采。