West Fork Whiterocks River, Utah: stable isotope and hydrochemical data for rock glacier water, streamwater, and groundwater

Water draining from rock glaciers in the Uinta Mountains of Utah (USA) was analyzed and compared with samples of groundwater and water from the master stream in a representative 5000-ha drainage. Samples were collected during the melt season of 2021 using automated ISCO samplers. Two samplers were installed at springs discharging from the termini of rock glaciers. A third sampler was installed at a non-rock glacier spring, and the fourth was deployed along the West Fork Whiterocks River. Composite samples of summer and fall rain were also collected, as well as grab samples of snow. Samples were analyzed for their stable isotopic composition using a Los Gatos 45-EP Triple Liquid Water Isotope Analyzer at Middlebury College. Samples were run against a bracketing set of 5 standards and calibrated with a cubic spline function. Each sample was analyzed 10 times, with the first 2 injections discarded to minimize cross-over. Standards were run as unknowns after every five samples as an internal check on the results. Accuracy of the instrument is 0.4‰ for δD and 0.1‰ for δ18O. The standard deviation of repeat injections of the samples in this study was 0.17‰ for δD and 0.04‰ for δ18O. Hydrochemical characterizations were made with a Thermo iCap ICP-MS at Middlebury College. Samples were run against a set of standards derived from NIST Standard Reference Material 1643f “Trace Elements in Water”. An in-house standard was used to determine the abundance of Si and Ti, which are not present in 1643f. The NIST standard and the in-house standards were run after every 10 unknowns and a linear correction was applied to compensate for instrument drift. Interpretation focused on elements that consistently exhibited concentrations >1 ppb.

对美国犹他州尤因塔山脉（Uinta Mountains）的冰砾阜（rock glaciers）融水开展分析，并与代表性5000公顷流域内的地下水及主河道水样进行对比。本次研究于2021年融雪季期间，采用自动化ISCO采样器完成水样采集：在两处源自冰砾阜末端的泉眼各安装一台采样器，第三台部署于非冰砾阜泉眼，第四台则设于怀特罗克斯河西支流沿岸。此外还采集了夏秋季降雨的混合水样与瞬时雪样。所有水样均于明德学院（Middlebury College）采用洛斯加托斯45-EP型液态水同位素分析仪（Los Gatos 45-EP Triple Liquid Water Isotope Analyzer）进行稳定同位素组成分析：分析时以5组标准样品作为插样校准标准，并通过三次样条函数完成校准；每个样品重复分析10次，弃去前2次进样以最小化进样交叉污染。每完成5个样品的分析后，将标准样品作为未知样进行检测，以开展内部质量控制。该仪器的检测准确度为：δD值0.4‰，δ18O值0.1‰；本次研究中样品重复进样的标准偏差为：δD值0.17‰，δ18O值0.04‰。水化学特征表征工作同样于明德学院开展，采用赛默飞iCAP型电感耦合等离子体质谱仪（Thermo iCAP ICP-MS）完成分析：分析时采用源自美国国家标准与技术研究院（National Institute of Standards and Technology, NIST）标准参考物质1643f《水中痕量元素》（NIST Standard Reference Material 1643f "Trace Elements in Water"）的标准溶液进行校准；针对该标准物质中未包含的硅（Si）与钛（Ti），采用实验室内部标准溶液确定其浓度。每分析10个未知样品后，即插入NIST标准溶液与内部标准溶液进行检测，并通过线性校正补偿仪器漂移。本次研究的分析重点聚焦于浓度持续高于1纳克每升（ppb）的元素。