Hydrogeology of desert springs in the Panamint Range, California, USA : Geologic controls on the geochemical kinetics, flowpaths, and mean residence times of springs
Hydrogeology of desert springs in the Panamint Range, California, USA : Geologic controls on the geochemical kinetics, flowpaths, and mean residence times of springs
复制标题
美国加利福尼亚州帕纳明特山脉沙漠泉水的水文地质：对泉水地球化学动力学、流动路径和平均停留时间的地质控制
DOI：
10.1002/hyp.13776
复制
发表时间：
2020
影响因子：
3.2
通讯作者：
Hedlund, Brian P.
中科院分区：
文献类型：
--
作者：
Gleason, Carolyn L.;Frisbee, Marty D.;Rademacher, Laura K.;Sada, Donald W.;Meyers, Zachary P.;Knott, Jeffrey R.;Hedlund, Brian P.
在加利福尼亚州死亡谷国家公园附近的帕纳明特山脉中，有超过180处泉水，尽管这些泉水在文化、历史和生态上具有重要意义，但它们很少受到水文地质学的关注。在这里，我们解决以下问题：（1）哪些岩石单元支持地下水流向帕纳明特山脉的泉水，（2）这些含水层的地球化学动力学是什么，以及（3）这些泉水的停留时间是什么？所有的泉水至少部分地受到补给的支持，并流经白云岩单位，即中午白云岩，金斯顿峰形成，约翰尼形成。因此，泉水的地球化学成分可以很大程度上用去泥化作用来解释：白云石和石膏的溶解与方解石的同时沉淀。然而，与热液矿床的相互作用可能影响了桑代克泉、最高泉、哈纳帕峡谷泉和特雷尔峡谷泉的地球化学成分。断裂是控制春季出苗的重要因素。21个样本中有17个出现在断层处（13个出现在低角度拆离断层处）。在帕纳明特山脉的东侧，泉水出现在低角度断层与几乎垂直的晚元古代、寒武纪和奥陶纪沉积单元相交的地方。这些地质单元不存在于帕纳明特山脉的西侧。相反，西侧的泉水出现在低角度断层与新生代角砾岩和fanglomerate相交的地方。泉水的平均停留时间从33（±30）年到1，829（±613）年不等。共有11个泉水的平均停留时间相对较短，不到500年，而7个泉水的平均停留时间超过1,000年。我们推断，帕纳明特山脉的泉水非常容易受到气候变化的影响，因为它们依赖于当地的补给，与区域地下水流（死亡谷区域水流系统-DVRFS）断开，与DVRFS支持的泉水相比，平均停留时间相对较短（例如，阿什梅多斯国家野生动物保护区（Ash Meadows National Wildlife Refuge）事实上，在这次竞选期间，有四股泉水没有流动，但它们在20世纪90年代和2000年代却流动了。
Over 180 springs emerge in the Panamint Range near Death Valley National Park, CA, yet, these springs have received very little hydrogeological attention despite their cultural, historical, and ecological importance. Here, we address the following questions: (1) which rock units support groundwater flow to springs in the Panamint Range, (2) what are the geochemical kinetics of these aquifers, and (3) and what are the residence times of these springs? All springs are at least partly supported by recharge in and flow through dolomitic units, namely, the Noonday Dolomite, Kingston Peak Formation, and Johnnie Formation. Thus, the geochemical composition of springs can largely be explained by dedolomitization: the dissolution of dolomite and gypsum with concurrent precipitation of calcite. However, interactions with hydrothermal deposits have likely influenced the geochemical composition of Thorndike Spring, Uppermost Spring, Hanaupah Canyon springs, and Trail Canyon springs. Faults are important controls on spring emergence. Seventeen of twenty‐one sampled springs emerge at faults (13 emerge at low‐angle detachment faults). On the eastern side of the Panamint Range, springs emerge where low‐angle faults intersect nearly vertical Late Proterozoic, Cambrian, and Ordovician sedimentary units. These geologic units are not present on the western side of the Panamint Range. Instead, springs on the west side emerge where low‐angle faults intersect Cenozoic breccias and fanglomerates. Mean residence times of springs range from 33 (±30) to 1,829 (±613) years. A total of 11 springs have relatively short mean residence times less than 500 years, whereas seven springs have mean residence times greater than 1,000 years. We infer that the Panamint Range springs are extremely vulnerable to climate change due to their dependence on local recharge, disconnection from regional groundwater flow (Death Valley Regional Flow System ‐ DVRFS), and relatively short mean residence times as compared with springs that are supported by the DVRFS (e.g., springs in Ash Meadows National Wildlife Refuge). In fact, four springs were not flowing during this campaign, yet they were flowing in the 1990s and 2000s.