Rapid field application of hydraulic tomography for resolving aquifer heterogeneity in unconsolidated sediments

Abstract

[1] A new framework is introduced for hydraulic tomography application and validation in the field. Our motivation is the need for methods that are both efficient and expressive for resolving the spatial distribution of heterogeneous hydraulic properties in aquifers. The presented strategy involves time-efficient field experiments and a computationally efficient inversion scheme. By exploiting the early travel time diagnostics of the hydraulic pressure pulses recorded during tomographic cross-well tests, and new application of attenuation inversion, only short-term pumping tests are required. Many of these can be conducted in one day. The procedure is developed by a numerical experiment with a highly heterogeneous aquifer analogue and then applied to a field case with a shallow, unconsolidated sedimentary aquifer, the Stegem€ uhle site in Germany. It is demonstrated that the performance of a suite of tomographic short-term pumping tests, data processing and inversion for the reconstruction of heterogeneous diffusivity and specific storage distribution is possible within one day. Additionally, direct-push injection logging is performed at the field site, and the obtained field data is utilized for successful validation of the hydraulic tomograms. We also compare both methods with respect to the necessary requirements, time demand in the field and complexity of interpretation.Citation: Brauchler, R., R. Hu, L. Hu, S. Jim enez, P. Bayer, P. Dietrich, and T. Ptak (2013), Rapid field application of hydraulic tomography for resolving aquifer heterogeneity in unconsolidated sediments, Water Resour.

Hydraulic Tomography: Continuity and Discontinuity of High‐K and Low‐K Zones

“…3D transient HT (THT) involves conducting a series of discrete‐interval pumping tests with discrete‐interval pressure observations at multiple locations, and the data are analyzed through inversion of all tests together. HT has been evolving over the past two decades (Gottlieb and Dietrich ); numerical and laboratory examples have contributed to HT operational improvements including increased effectiveness in observation types, times, and networks (e.g., Cardiff et al ; Sun et al ), and in computational efficiencies (Liu and Kitanidis ; Brauchler et al ; Cardiff et al ; Jiménez et al ; Liu et al , ; Lee and Kitanidis ). Cardiff and Barrash () provided a comprehensive summary of 2D and 3D HT studies.…”

Travel-time-based thermal tracer tomography

“…To improve spatial resolution, they applied staggered grids (Vesnaver and Böhm, 2000) during inversion. This inversion methodology was applied to several hydraulic laboratory and field experiments (Brauchler et al, 2007(Brauchler et al, , 2013bHu et al, 2011;Jiménez et al, 2013). Brauchler et al (2013a) also utilized travel times in a tracer experiment on rock samples on the laboratory scale.…”

Identification of groundwater flow parameters using reciprocal data from hydraulic interference tests

“…In this context, modern field investigations on aquifers are oriented toward the so-called hydraulic tomography, a flavor of which is based on the concept that performing multiple hydraulic tests in a suite of wells would increase our ability to probe flow conditions and achieve improved control on model parameter identification (e.g., Brauchler et al, 2013;Illman, 2014). As application-oriented examples, experimental observations from hydraulic tomography campaigns based on slug tests and interference testing between wells have been employed in various analytical and numerical models to estimate hydraulic parameters in highly heterogeneous karstic aquifers (Audouin et al, 2008;Riva et al, 2009;Trottier et al, 2014).…”