Using earth‐tide induced water pressure changes to measure in situ permeability: A comparison with long‐term pumping tests
Using earth‐tide induced water pressure changes to measure in situ permeability: A comparison with long‐term pumping tests
复制标题
DOI：
10.1002/2015wr017346
复制
发表时间：
2016-04
影响因子：
5.4
通讯作者：
V. Allègre;E. Brodsky;L. Xue;S. Nale;B. Parker;J. Cherry
中科院分区：
文献类型：
--
作者：
V. Allègre;E. Brodsky;L. Xue;S. Nale;B. Parker;J. Cherry
对水文地质性质的良好约束是建立任何地下水流量定量模型的重要第一步。渗透率的现场估计是困难的，因为它在自然系统中变化超过数量级，并且依赖于规模。在这里，我们直接比较了从潮汐反应中推断出的渗透率与在同一地点进行的常规大规模长期抽水试验。利用井中记录的潮汐引起的水压变化来推断密集裂缝砂岩单元中十个位置的渗透率。每个位置既可以是裸眼井，也可以是多级监测井中的一个端口。将每个地点的潮汐响应与在同一地点进行的两次常规、长期和大规模抽水试验的结果进行比较。对于大开井段的裸眼井和多井段的监测井，我们在不同的方法之间获得了一致的点特异性渗透率范围，从~ 10 - 15 m2到10 - 13 m2不等。我们得出结论，潮汐分析能够捕获被动和准确的渗透率估计。
Good constraints on hydrogeological properties are an important first step in any quantitative model of groundwater flow. Field estimation of permeability is difficult as it varies over orders of magnitude in natural systems and is scale‐dependent. Here we directly compare permeabilities inferred from tidal responses with conventional large‐scale, long‐term pumping tests at the same site. Tidally induced water pressure changes recorded in wells are used to infer permeability at ten locations in a densely fractured sandstone unit. Each location is either an open‐hole well or a port in a multilevel monitoring well. Tidal response is compared at each location to the results of two conventional, long‐term and large scale pumping tests performed at the same site. We obtained consistent values between the methods for a range of site‐specific permeabilities varying from ∼10−15 m2 to 10−13 m2 for both open wells with large open intervals and multilevel monitoring well. We conclude that the tidal analysis is able to capture passive and accurate estimates of permeability.