Distributed!temperature!sensing!(DTS)!as!a!hydrostratigraphic!characterization!tool

Subsurface heterogeneity in hydraulic properties and processes is a fundamental challenge in hydrogeology. Most hydrogeologic problems are complicated by uncertainty in permeability, which is often difficult or impossible to fully characterize. The usefulness of heat as a tracer has been limited by thermometry that only records temporal changes in temperature at a single fixed or moving point. Distributed temperature sensing (DTS) is a powerful new method that allows for the nearly continuous measurement of temperature in time and space along fiber-optic cables. The fine spatial and temporal monitoring ability of DTS is creating new and unprecedented opportunities to study hydraulic heterogeneity at a wide range of scales. Despite numerous recent applications of DTS applications in surface water investigations, down-hole uses in hydrogeology have been limited. Recent studies on the Sandstone Aquifer system of Wisconsin have shown preferential flow through laterally continuous bedding plane
fractures to be a defining characteristic of sandstone units that were traditionally assumed to be homogeneous and isotropic. The implication of these findings is that more detailed characterization efforts are necessary to adequately assess flow and transport problems in these units.

Raw project data is available by contacting [e-mail]

地下水层在水分力学性质与过程方面的非均质性构成了水文地质学中的一个基本挑战。大多数水文地质问题均因渗透率的不确定性而变得复杂，而渗透率的全面表征往往难以实现，甚至无法实现。由于仅能记录单一固定或移动点的温度随时间变化，热能作为示踪剂的应用价值受到了限制。分布式温度传感技术（DTS）作为一种新颖且强大的方法，允许在光纤电缆上近乎连续地测量时间和空间上的温度。DTS在时空尺度上的精细监测能力为研究不同尺度上的水分非均质性创造了前所未有的新机遇。尽管分布式温度传感技术在表面水研究中的应用日益增多，但在水文地质学中的井下应用仍较为有限。近期对威斯康星州砂岩含水层系统的研究显示，侧向连续的层理面裂缝中的优先流是传统上被认为均质各向同性的砂岩单元的一个显著特征。这些发现的意义在于，对这些单元中的流动和传输问题进行充分评估需要更多的详细表征工作。原始项目数据可通过联系 [e-mail] 获取。