Abstract Radiogenic strontium isotopic ratios (87Sr/86Sr) and solute concentrations in groundwater samples from the coastal area of the eastern Yucatan Peninsula, Quintana Roo, Mexico were measured to assess connectivity and water-rock interactions within different groundwater systems in the region. The average 87Sr/86Sr ratios vary from south to north with values in Xcalak around 0.70889, Sian Ka'an around 0.70847 and at Cancun and Puerto Morelos around 0.70880. The values show 3 clusters suggesting 3 distinct groundwater systems, Cancun-Puerto Morelos in the north, Tulum-Sian Ka'an in the center and Xcalak in the South. Water-rock interactions, while unique within each aquifer system, encompass processes observed throughout the Yucatan karst system including dissolution of evaporites, precipitation of carbonate, sulfate reduction and mixing with seawater. This study highlights the use of groundwater chemistry of understanding groundwater connectivity and the importance of potential distal anthropogenic impacts on groundwater quality and related effect on coastal population and ecosystems.

中文翻译：

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地下水化学和 Sr 同位素比率揭示了墨西哥加勒比海岸沿海含水层的连通性和水-岩相互作用

摘要 测量了墨西哥金塔纳罗奥州尤卡坦半岛东部沿海地区地下水样品中放射性锶同位素比 (87Sr/86Sr) 和溶质浓度，以评估该地区不同地下水系统的连通性和水-岩相互作用。平均 87Sr/86Sr 比率从南到北各不相同，Xcalak 的值约为 0.70889，Sian Ka'an 的值约为 0.70847，坎昆和莫雷洛斯港的值约为 0.70880。这些值显示了 3 个集群，表明了 3 个不同的地下水系统，北部的坎昆-莫雷洛斯港、中部的图卢姆-西安卡安和南部的 Xcalak。水-岩相互作用虽然在每个含水层系统中都是独一无二的，但包括在整​​个尤卡坦岩溶系统中观察到的过程，包括蒸发岩的溶解、碳酸盐的沉淀、硫酸盐还原并与海水混合。本研究强调了利用地下水化学来了解地下水连通性以及远侧人为影响对地下水质量的潜在影响以及对沿海人口和生态系统的相关影响的重要性。