Collaborative Research: Application of Fe and Zn isotopes to fingerprint, track, and quantify metal fluxes in streams and groundwater in alpine watersheds

摘要高山流域最终满足了美国西部大部分地区的饮用、农业和工业用水需求，也是世界范围内重要的水源。许多高山流域的一个主要问题是金属污染，或来自废弃的采矿作业，或来自自然来源。为了设计和优先考虑有效的水管理和修复策略，我们需要确定重要的金属来源，并了解金属负荷在不同时空尺度上的变化。我们将以一种新的方式解决这个问题——通过使用新兴的铁和锌同位素工具来指纹金属来源，并确定受酸性富金属水影响的山区集水区的金属运输过程。我们的研究框架旨在促进三个主要领域的科学理解：1)区分地下水排放到地表水的铁和锌负荷，而不是地表径流；2)区分铁和锌的人为来源和自然来源；3)将铁和锌同位素的季节变化与水文地球化学变化联系起来。我们将通过将我们的发现整合到评估高山水域金属污染的概念模型中来完成我们的项目。我们的研究计划包括在科罗拉多州的Prospect和Handcart峡谷对水（溶解和悬浮负载）和岩石进行有针对性的实地采样，并对富含硫化物的矿物分离进行补充实验室实验。这两个地点都受到了金属污染，而且通过现有的监测井网络，还可以获得地下水。我们还将利用金属来源的差异（人为与自然）以及这些流域地下水与地表水关系的不同来检验我们的假设。我们的建议是合作的，将美国地质调查局的专业知识和资源与PI Borrok和德克萨斯大学埃尔帕索分校（UTEP）地质科学系的学生结合起来。我们的工作将特别扩大UTEP中代表性不足的学生的参与。UTEP是美国唯一一所以墨西哥裔美国学生为主的研究型博士大学。为了进一步增加教育机会，我们与位于科罗拉多州锡尔弗顿的独立研究/教育机构和高山野外研究站Mountain Studies Institute建立了合作关系。我们会使用MSI吗？为我们在展望峡谷的野外工作提供食宿、野外实验室和教育设施。与美国地质勘探局和MSI的合作将使UTEP的学生能够使用尖端的设备/设施，并参与广泛的研究经验。

Collaborative Research: Application of Fe and Zn Isotopes to Fingerprint, Track, and Quantify Metal Fluxes in Streams and Groundwater in Alpine WatershedsAbstractAlpine watersheds ultimately support the drinking, agricultural, and industrial water needs for most of the western United States, and are critical sources of water worldwide. A key concern in many alpine watersheds is metal contamination, either from abandoned mining operations or from natural sources. In order to design and prioritize useful water management and remediation strategies, we need to identify important metal sources and understand how metal loads change over different spatial and temporal scales. We will attack this problem in a new way - by using the emerging tools of Fe and Zn isotopes to fingerprint metal sources and to identify metal transport processes in mountain catchments impacted by acidic, metal-rich waters. We have framed this investigation to advance scientific understanding in three main areas: 1) Distinguishing between Fe and Zn loads that are attributable to groundwater discharge to surface-water as opposed to surface runoff, 2) Distinguishing between anthropogenic and natural sources of Fe and Zn, and 3) Correlating seasonal changes in Fe and Zn isotopes with hydrogeochemical changes. We will complete our project by integrating our findings into a conceptual model for evaluating metal contamination in alpine waters. Our research plan includes targeted field sampling of waters (both dissolved and suspended loads) and rocks in Prospect and Handcart Gulches in Colorado, and complementary lab experiments with sulfide-rich mineral separates. Both field sites are contaminated with metals and include remarkable access to groundwater through existing networks of monitoring wells. We will also take advantage of differences in metal sources (anthropogenic vs. natural) and in dissimilar groundwater-surface water relationships in these watersheds to test our hypotheses. Our proposal is collaborative, combining the expertise and resources within the U. S. Geological Survey with PI Borrok and students in the Department of Geological Sciences at the University of Texas at El Paso (UTEP). Our work will specifically broaden participation from underrepresented students already at UTEP. UTEP is the only research-intensive doctoral university in the U.S. with a Mexican-American majority student population. To further enhance educational opportunities, we have partnered with the Mountain Studies Institute, an independent research/education institution and alpine field station in Silverton, Colorado. We will utilize the MSI?s boarding, field laboratory, and educational facilities for our field work in Prospect Gulch. Partnerships with the USGS and MSI will allow students at UTEP access to cutting-edge equipment/facilities and to participate in a broad range of research experiences.