The Grand Canyon provides a deeply dissected view of the aquifers of the Colorado Plateau and its public and tribal lands. Stacked sandstone and karst aquifers are vertically connected by a network of faults and breccia pipes creating a complex groundwater network. Hydrochemical variations define structurally controlled groundwater sub-basins, each with main discharging springs. North Rim (N-Rim), South Rim (S-Rim), and far-west springs have different stable isotope fingerprints, reflecting different mean recharge elevations. Variation within each region reflects proportions of fast/slow aquifer pathways. Often considered perched, the upper Coconino (C) aquifer has a similar compositional range as the regional Redwall-Muav (R-M) karst aquifer, indicating connectivity. Natural and anthropogenic tracers show that recharge can travel 2 km vertically and tens of kilometers laterally in days to months via fracture conduits to mix with older karst baseflow. Six decades of piping N-Rim water to S-Rim Village and infiltration of effluent along the Bright Angel fault have sustained S-Rim groundwaters and likely induced S-Rim microseismicity. Sustainable groundwater management and uranium mining threats require better monitoring and application of hydrotectonic concepts. ▪Hydrotectonic concepts include distinct structural sub-basins, fault fast conduits, confined aquifers, karst aquifers, upwelling geothermal fluids, and induced seismicity.▪N-Rim, S-Rim, and far-west springs have different stable isotope fingerprints reflecting different mean recharge elevations and residence times.▪The upper C and lower R-M aquifers have overlapping stable isotope fingerprints in a given region, indicating vertical connectivity between aquifers.▪S-Rim springs and groundwater wells are being sustained by ∼60 years of piping of N-Rim water to S-Rim, possibly inducing seismicity.

中文翻译：

---

大峡谷地下水的水文构造


大峡谷提供了科罗拉多高原含水层及其公共和部落土地的深度剖析视图。堆积的砂岩和喀斯特含水层通过断层和角砾岩管网络垂直连接，形成复杂的地下水网络。水化学变化定义了结构受控的地下水子流域，每个子流域都有主要的排放泉。北缘 （N-Rim）、南缘 （S-Rim） 和远西泉具有不同的稳定同位素指纹，反映了不同的平均补给海拔。每个区域内的变化反映了快/慢含水层途径的比例。科科尼诺 （C） 上部含水层通常被认为是栖息的，其成分范围与区域性红墙-穆阿夫 （R-M） 喀斯特含水层相似，表明连通性。自然和人为示踪剂表明，补给可以在几天到几个月内通过裂缝管道与旧的喀斯特基流混合，垂直行进 2 公里，横向行进数十公里。六十年来，将 N 环水输送到 S 环村，并沿着 Bright Angel 断层渗入污水，维持了 S 环地下水，并可能诱发了 S 环微震。可持续的地下水管理和铀矿开采威胁需要更好地监测和应用水文构造概念。▪水文构造概念包括不同的构造子流域、断层快速管道、承压含水层、岩溶含水层、上升流地热流体和诱发地震活动。▪N-Rim、S -Rim 和远西泉具有不同的稳定同位素指纹，反映了不同的平均补给高程和停留时间。▪上 C 和下 R-M 含水层在给定区域中具有重叠的稳定同位素指纹，表明含水层之间的垂直连通性。▪S 环泉和地下水井由 N 环水到 S 环大约 60 年的管道维持，可能会诱发地震。