The geochemical and isotopic characteristics of groundwaters in Chimayó, New Mexico, reflect processes that affect water quality in the Tesuque Aquifer, which overlies a leaking natural CO₂ source in a structurally complex region. In this study, select isotopes (δ¹³C, ⁸⁷Sr/⁸⁶Sr, ²³⁴U/²³⁸U) are applied to groundwaters to better understand CO₂ transport mechanisms and related water-rock interactions that impact Chimayó groundwater. Carbon stable isotope ratios of dissolved inorganic carbon (DIC; δ¹³C_DIC = -15.10‰ to 4.50‰) identify a distinct source of upward-migrating CO₂ that interacts with the groundwater. Groundwater ⁸⁷Sr/⁸⁶Sr compositions (0.7098 to 0.7154) reflect intrusion of varying amounts of saline water associated with the high CO₂ source, while ²³⁴U/²³⁸U ratios corroborate presence of deep groundwater and suggest impacts from distinctive natural uranium sources are affecting groundwater. Previous work proposed two CO₂ transport mechanisms at the site: (1) dissolved in deep brine that underlies the aquifer and (2) in the gas phase; this study uses isotope mixing models to identify wells that are affected by these CO₂ transport mechanisms and demonstrates that both transport mechanisms are associated with impaired groundwaters. Overall, this study demonstrates that applying multiple isotope systems (δ¹³C_DIC, ⁸⁷Sr/⁸⁶Sr, ²³⁴U/²³⁸U) is a dynamic tool for identifying and measuring the impact of CO₂ leakage from a sequestration site.

新墨西哥州奇马约的地下水的地球化学和同位素特征反映了影响Tesuque含水层中水质的过程，Tesuque含水层覆盖了结构复杂区域中泄漏的天然CO ₂源。在这项研究中，选择的同位素（δ ¹³ C，⁸⁷ SR / ⁸⁶的Sr，²³⁴ U / ²³⁸ U）被施加到地下水，以更好地理解CO ₂输送机构和相关的水岩相互作用，其冲击奇马约地下水。溶解的无机碳的碳的稳定同位素比（DIC;δ ¹³ C ^ _DIC = -15.10‰至4.50‰）识别的不同的源向上迁移CO ₂与地下水相互作用。地下水⁸⁷ Sr / ⁸⁶ Sr组成（0.7098至0.7154）反映了与高CO ₂源相关的不同量盐水的入侵，而²³⁴ U / ²³⁸ U比值证实了深层地下水的存在，并表明来自独特天然铀源的影响地下水。先前的工作提出了现场的两种CO ₂传输机理：（1）溶解在含水层下的深盐水中；（2）在气相中；这项研究使用同位素混合模型来识别受这些CO ₂影响的井传输机制，并证明这两种传输机制都与地下水受损有关。总体而言，本研究证实了应用多个同位素系统（δ ¹³ Ç _DIC，⁸⁷ SR / ⁸⁶的Sr，²³⁴ U / ²³⁸ U）是用于识别和测量CO的影响的动态工具₂泄漏从多价螯合位点。