Articles | Volume 12, issue 7
https://doi.org/10.5194/se-12-1497-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/se-12-1497-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Four-dimensional tracer flow reconstruction in fractured rock through borehole ground-penetrating radar (GPR) monitoring
Peter-Lasse Giertzuch
CORRESPONDING AUTHOR
Institute of Geophysics, ETH Zurich, Zurich, Switzerland
Joseph Doetsch
Institute of Geophysics, ETH Zurich, Zurich, Switzerland
Lufthansa Industry Solutions, Raunheim, Germany
Alexis Shakas
Institute of Geophysics, ETH Zurich, Zurich, Switzerland
Mohammadreza Jalali
Department of Engineering Geology and Hydrogeology, RWTH Aachen, Aachen, Germany
Bernard Brixel
Geological Institute, ETH Zurich, Zurich, Switzerland
Hansruedi Maurer
Institute of Geophysics, ETH Zurich, Zurich, Switzerland
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Kathrin Behnen, Marian Hertrich, Hansruedi Maurer, Alexis Shakas, Kai Bröker, Claire Epiney, María Blanch Jover, and Domenico Giardini
Solid Earth, 16, 333–350, https://doi.org/10.5194/se-16-333-2025, https://doi.org/10.5194/se-16-333-2025, 2025
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Several cross-hole seismic surveys in the undisturbed Rotondo granite are used to analyze the seismic anisotropy in the Bedretto Lab, Switzerland. The P and S1 waves show a clear trend of faster velocities in the NE–SW direction and slower velocities perpendicular to it, indicating a tilted transverse isotropic velocity model. The symmetry plane is mostly aligned with the direction of maximum stress, but also the orientation of fractures is expected to influence the velocities.
Raphael Burchartz, Timo Seemann, Garri Gaus, Lisa Winhausen, Mohammadreza Jalali, Brian Mutuma Mbui, Sebastian Grohmann, Linda Burnaz, Marlise Colling Cassel, Jochen Erbacher, Ralf Littke, and Florian Amann
EGUsphere, https://doi.org/10.5194/egusphere-2025-579, https://doi.org/10.5194/egusphere-2025-579, 2025
This preprint is open for discussion and under review for Solid Earth (SE).
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In Germany, claystones are studied for their suitability as host-rocks for the disposal of high-level radioactive waste. The MATURITY project systematically investigates how gradual burial affects key barrier properties in the Lower Jurassic Amaltheenton Formation of the Lower Saxony Basin (Germany). Understanding these changes helps assess claystone suitability for long-term waste isolation, improving site selection for deep geological repositories.
Peter Achtziger-Zupančič, Alberto Ceccato, Alba Simona Zappone, Giacomo Pozzi, Alexis Shakas, Florian Amann, Whitney Maria Behr, Daniel Escallon Botero, Domenico Giardini, Marian Hertrich, Mohammadreza Jalali, Xiaodong Ma, Men-Andrin Meier, Julian Osten, Stefan Wiemer, and Massimo Cocco
Solid Earth, 15, 1087–1112, https://doi.org/10.5194/se-15-1087-2024, https://doi.org/10.5194/se-15-1087-2024, 2024
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We detail the selection and characterization of a fault zone for earthquake experiments in the Fault Activation and Earthquake Ruptures (FEAR) project at the Bedretto Lab. FEAR, which studies earthquake processes, overcame data collection challenges near faults. The fault zone in Rotondo granite was selected based on geometry, monitorability, and hydro-mechanical properties. Remote sensing, borehole logging, and geological mapping were used to create a 3D model for precise monitoring.
Sebastian Hellmann, Melchior Grab, Cedric Patzer, Andreas Bauder, and Hansruedi Maurer
Solid Earth, 14, 805–821, https://doi.org/10.5194/se-14-805-2023, https://doi.org/10.5194/se-14-805-2023, 2023
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Acoustic waves are suitable to analyse the physical properties of the subsurface. For this purpose, boreholes are quite useful to deploy a source and receivers in the target area to get a comprehensive high-resolution dataset. However, when conducting such experiments in a subsurface such as glaciers that continuously move, the boreholes get deformed. In our study, we therefore developed a method that allows an analysis of the ice while considering deformations.
Lisa Maria Ringel, Mohammadreza Jalali, and Peter Bayer
Hydrol. Earth Syst. Sci., 26, 6443–6455, https://doi.org/10.5194/hess-26-6443-2022, https://doi.org/10.5194/hess-26-6443-2022, 2022
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Fractured rocks host a class of aquifers that serve as major freshwater resources worldwide. This work is dedicated to resolving the three-dimensional hydraulic and structural properties of fractured rock. For this purpose, hydraulic tomography experiments at the Grimsel Test Site in Switzerland are utilized, and the discrete fracture network is inverted. The comparison of the inversion results with independent findings from other studies demonstrates the validity of the approach.
Lisa Winhausen, Kavan Khaledi, Mohammadreza Jalali, Janos L. Urai, and Florian Amann
Solid Earth, 13, 901–915, https://doi.org/10.5194/se-13-901-2022, https://doi.org/10.5194/se-13-901-2022, 2022
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Triaxial compression tests at different effective stresses allow for analysing the deformation behaviour of Opalinus Clay, the potential host rock for nuclear waste in Switzerland. We conducted microstructural investigations of the deformed samples to relate the bulk hydro-mechanical behaviour to the processes on the microscale. Results show a transition from brittle- to more ductile-dominated deformation. We propose a non-linear failure envelop associated with the failure mode transition.
Xiaodong Ma, Marian Hertrich, Florian Amann, Kai Bröker, Nima Gholizadeh Doonechaly, Valentin Gischig, Rebecca Hochreutener, Philipp Kästli, Hannes Krietsch, Michèle Marti, Barbara Nägeli, Morteza Nejati, Anne Obermann, Katrin Plenkers, Antonio P. Rinaldi, Alexis Shakas, Linus Villiger, Quinn Wenning, Alba Zappone, Falko Bethmann, Raymi Castilla, Francisco Seberto, Peter Meier, Thomas Driesner, Simon Loew, Hansruedi Maurer, Martin O. Saar, Stefan Wiemer, and Domenico Giardini
Solid Earth, 13, 301–322, https://doi.org/10.5194/se-13-301-2022, https://doi.org/10.5194/se-13-301-2022, 2022
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Questions on issues such as anthropogenic earthquakes and deep geothermal energy developments require a better understanding of the fractured rock. Experiments conducted at reduced scales but with higher-resolution observations can shed some light. To this end, the BedrettoLab was recently established in an existing tunnel in Ticino, Switzerland, with preliminary efforts to characterize realistic rock mass behavior at the hectometer scale.
Lisa Winhausen, Mohammadreza Jalali, and Florian Amann
Saf. Nucl. Waste Disposal, 1, 301–301, https://doi.org/10.5194/sand-1-301-2021, https://doi.org/10.5194/sand-1-301-2021, 2021
Gregory Church, Andreas Bauder, Melchior Grab, and Hansruedi Maurer
The Cryosphere, 15, 3975–3988, https://doi.org/10.5194/tc-15-3975-2021, https://doi.org/10.5194/tc-15-3975-2021, 2021
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In this field study, we acquired a 3D radar survey over an active drainage network that transported meltwater through a Swiss glacier. We successfully imaged both englacial and subglacial pathways and were able to confirm long-standing glacier hydrology theory regarding meltwater pathways. The direction of these meltwater pathways directly impacts the glacier's velocity, and therefore more insightful field observations are needed in order to improve our understanding of this complex system.
Sebastian Hellmann, Melchior Grab, Johanna Kerch, Henning Löwe, Andreas Bauder, Ilka Weikusat, and Hansruedi Maurer
The Cryosphere, 15, 3507–3521, https://doi.org/10.5194/tc-15-3507-2021, https://doi.org/10.5194/tc-15-3507-2021, 2021
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In this study, we analyse whether ultrasonic measurements on ice core samples could be employed to derive information about the particular ice crystal orientation in these samples. We discuss if such ultrasonic scans of ice core samples could provide similarly detailed results as the established methods, which usually destroy the ice samples. Our geophysical approach is minimally invasive and could support the existing methods with additional and (semi-)continuous data points along the ice core.
Sebastian Hellmann, Johanna Kerch, Ilka Weikusat, Andreas Bauder, Melchior Grab, Guillaume Jouvet, Margit Schwikowski, and Hansruedi Maurer
The Cryosphere, 15, 677–694, https://doi.org/10.5194/tc-15-677-2021, https://doi.org/10.5194/tc-15-677-2021, 2021
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We analyse the orientation of ice crystals in an Alpine glacier and compare this orientation with the ice flow direction. We found that the crystals orient in the direction of the largest stress which is in the flow direction in the upper parts of the glacier and in the vertical direction for deeper zones of the glacier. The grains cluster around this maximum stress direction, in particular four-point maxima, most likely as a result of recrystallisation under relatively warm conditions.
Gregory Church, Melchior Grab, Cédric Schmelzbach, Andreas Bauder, and Hansruedi Maurer
The Cryosphere, 14, 3269–3286, https://doi.org/10.5194/tc-14-3269-2020, https://doi.org/10.5194/tc-14-3269-2020, 2020
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In this field study, we repeated ground-penetrating radar measurements over an active englacial channel network that transports meltwater through the glacier. We successfully imaged the englacial meltwater pathway and were able to delimitate the channel's shape. Meltwater from the glacier can impact the glacier's dynamics if it reaches the ice–bed interface, and therefore monitoring these englacial drainage networks is important to understand how these networks behave throughout a season.
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Short summary
Two time-lapse borehole ground penetrating radar (GPR) surveys were conducted during saline tracer experiments in weakly fractured crystalline rock with sub-millimeter fractures apertures, targeting electrical conductivity changes. The combination of time-lapse reflection and transmission GPR surveys from different boreholes allowed monitoring the tracer flow and reconstructing the flow path and its temporal evolution in 3D and provided a realistic visualization of the hydrological processes.
Two time-lapse borehole ground penetrating radar (GPR) surveys were conducted during saline...