Article
Chemistry, Physical
Tilo Kneuker, Reiner Dohrmann, Kristian Ufer, David Jaeggi
Summary: The research focused on the mineralogical and geochemical analysis of Opalinus Clay samples from Switzerland. It analyzed the degree of ordering of clay minerals and their impact on sorption and swelling properties. The study identified five main facies and emphasized the importance of combining lithofacial studies with mineralogical investigations.
APPLIED CLAY SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Nico Graebling, Ozgur Ozan Sen, Lars Bilke, Tuanny Cajuhi, Dmitri Naumov, Wenqing Wang, Gesa Ziefle, David Jaeggi, Jobst Massmann, Gerik Scheuermann, Olaf Kolditz, Karsten Rink
Summary: Underground Research Laboratories (URLs) allow large-scale geoscientific in-situ experiments. At Mont Terri URL in Switzerland, international research groups conduct numerous experiments, but the data obtained is often restricted to the researchers involved in the specific experiment.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Thermodynamics
Guang Hu, Martin Schoenball, Wilfried Pfingsten
Summary: Machine learning-assisted modelling can improve the safe operation of deep geological repositories (DGR). In this study, a ML-assisted 3D heat transport model for a mock-up DGR tunnel was developed and validated with experimental data. The results demonstrate the effectiveness of ML in predicting temperature evolution and identifying faulty sensor data. Rating: 9/10
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Geochemistry & Geophysics
Paul Wersin, Martin Mazurek, Thomas Gimmi
Summary: This study evaluates the porewater chemistry data obtained from different extraction methods in clayrocks and finds that the composition of porewater varies and is constrained by diffusive exchange, carbonate mineral and celestite equilibria.
APPLIED GEOCHEMISTRY
(2022)
Article
Geochemistry & Geophysics
Shingo Yokoyama, Misato Shimbashi, Daisuke Minato, Yasutaka Watanabe, Andreas Jenni, Urs Mader
Summary: The experiment revealed that the interaction between cement and bentonite can lead to various degrees of mineralogical changes, but over a 10-year period, detectable changes in the mineralogical nature of montmorillonite did not occur.
Article
Engineering, Geological
Yara Barakat, Yu-Jun Cui, Nadia Mokni, Pierre Delage, Frederic Bernier
Summary: This study investigates the dissolution of quartz and calcite minerals in Opalinus Clay under different pH conditions. The results show that quartz dissolution occurs significantly at pH higher than 11.5, while calcite dissolution occurs at pH higher than 8.5. The dissolution of quartz is mainly influenced by exposure time, while the dissolution of calcite depends on both exposure time and pH value.
ENGINEERING GEOLOGY
(2022)
Review
Engineering, Geological
Yara Barakat, Nadia Mokni, Yu-Jun Cui, Pierre Delage, Frederic Bernier
Summary: Three small-scale mock-up tests were conducted on Opalinus Clay samples to investigate the self-sealing behavior of fractures. The tests showed that synthetic water and alkaline solution may hinder the self-sealing process, while saline solutions can increase permeability and accelerate hydration but cannot completely seal the fractures.
CANADIAN GEOTECHNICAL JOURNAL
(2023)
Article
Geochemistry & Geophysics
Theresa Hennig, Michael Kuehn
Summary: The transport properties of potential host rocks for nuclear waste disposal are affected by hydro-geological boundaries and diffusion exchanges over millions of years. The influence of geochemical gradients and pCO2 on uranium migration in Opalinus Clay has been quantified, with pCO2 being the most influential parameter.
Article
Energy & Fuels
Dario Sciandra, Iman Rahimzadeh Kivi, Victor Vilarrasa, Roman Y. Makhnenko, Dorothee Rebscher
Summary: Ensuring the sealing capacity of caprocks is crucial as CO2 storage expands. Laboratory experiments with intact rock samples have shown that low-permeability and high-entry pressure caprocks have excellent sealing capacities. However, discontinuities such as bedding planes, fractures, and faults affect rock properties at the field scale and are challenging to monitor in industrial-scale applications. Underground Research Laboratories (URLs) provide an ideal setting to investigate the field-scale sealing capacity of caprocks, allowing for well-controlled experiments. The CO2 Long-term Periodic Injection Experiment (CO2LPIE) at the Mont Terri rock laboratory aims to study the advance of CO2 in Opalinus Clay, a clay-rich rock with bedding planes dipping at 45 degrees. By conducting hydro-mechanical simulations, researchers were able to predict the system response and design the experiment accordingly.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2022)
Article
Geosciences, Multidisciplinary
Tanner A. Shadoan, Jonathan B. Ajo-Franklin, Yves Guglielmi, Todd Wood, Michelle Robertson, Paul Cook, Florian Soom, Thomas M. Daley, Chet Hopp, Veronica Rodriguez Tribaldos, Pierpaolo Marchesini, Christophe Nussbaum, Jens Birkholzer
Summary: This study conducted a time-lapse seismic experiment to monitor a reactivated fault within the Opalinus clay formation at the Mont Terri Rock Laboratory. The measured changes in P-wave velocity were related to the opening of the fault damage zone, providing insights into changes in permeability within the fault zone. This research is important for predicting, detecting, and preventing CO2 movement.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Sina Hale, Xavier Ries, David Jaeggi, Philipp Blum
Summary: In this study, a hydromechanical characterization of an evolving excavation damaged zone (EDZ) in the Mont Terri underground rock laboratory in Switzerland was conducted using three different handheld devices. The study found permeable fractures with specific hydraulic apertures, observed cyclic long-term fracture aperture oscillations, and determined the uniaxial compressive strength of the rock. The study's methodological approach is suitable for time-dependent monitoring of EDZs, providing spatially resolved investigation of hydraulic and mechanical fracture apertures, surface roughness, and rock parameters.
Article
Environmental Sciences
Tilo Kneuker, Markus Furche
Summary: Opalinus Clay is a potential host rock for radioactive waste disposal, with varying lithological and structural variability captured through a multidisciplinary approach. Shaly facies types are found to be more homogenous, while sandy and carbonate-rich sandy facies represent the more heterogeneous lithofacies types. The varying resistivity is attributed to differences in clay mineral and carbonate content, with brittle faults observed throughout the investigated section.
ENVIRONMENTAL EARTH SCIENCES
(2021)
Article
Engineering, Geological
Lang Liu, Silvio B. Giger, Derek Martin, Rick Chalaturnyk, Kristof Schuster, Nathan Deisman, Lukas Keller
Summary: Opalinus Clay is the designated host rock for a deep geological repository of radioactive waste in Switzerland. The determination of its geo-mechanical properties relies heavily on laboratory tests on small specimens. The pressuremeter tests were performed in Opalinus Clay to assess its in-situ elastic stiffness at a larger scale. The shear modulus of the Opalinus Clay is dependent on the expansion pressure and exhibits a nonlinear dependence on strain increment.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Chemistry, Physical
Julio Goncalves, Jean-Michel Matray, Catherine Ji Yu
Summary: The relevant transport processes in clay media for deep geological disposal of radioactive waste, including the debated overpressures, were investigated in the Deep Borehole experiment at the Mont Terri URL. An anomalous pressure of about 13 bars was identified, and a multi-packer hydraulic system was used to determine the driving forces and transport coefficients. 1D transport models with osmotic processes were developed to reproduce the measured pressure and salinity profiles, showing the dominance of diffusion over advection at Mont Terri.
APPLIED CLAY SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Roman Esefelder, Britta Wawerzinek, Stefan Lueth, Ruediger Giese, Charlotte M. Krawczyk
Summary: Seismic anisotropy and attenuation make claystone formations difficult to characterize. However, high-resolution seismic tomography has proven to be a useful tool for structural and mechanical characterization at the scale of underground infrastructure. This study investigates the applicability of seismic tomography for the characterization of claystone formations from an underground rock laboratory under challenging on-site conditions including anisotropy, strong attenuation, and restricted acquisition geometry. The results show that considering anisotropy significantly enhances the tomographic results and demonstrates the ability of the approach to characterize heterogeneities of geological structures between rock laboratory galleries.
SWISS JOURNAL OF GEOSCIENCES
(2021)
Article
Geography, Physical
Dimitri Laurent, Christophe Durlet, Guillaume Barre, Patrick Sorriaux, Philippe Audra, Pierre Cartigny, Cedric Carpentier, Guillaume Paris, Pauline Collon, Thomas Rigaudier, Jacques Pironon, Eric C. Gaucher
Summary: Hypogenic caves, formed by deep waters rich in CO2 and H2S, make up over 10% of karstic networks worldwide. The interaction between hypogenic and epigenic processes is poorly understood, with the invasion of surface water often erasing markers of hypogenic activity. In the Ariege Valley, karstic networks have been reshaped by glacier meltwater, and deep fluids with CO2 and H2S played a key role in cave formation.
Article
Engineering, Geological
Leonardo Hax Damiani, Georg Kosakowski, Agnes Vinsot, Sergey Churakov
Summary: The Hydrogen Transfer experiment conducted at the Mont Terri underground rock laboratory in Switzerland is an in situ study that investigates the interaction and transport of injected hydrogen in Opalinus Clay, a type of claystone formation. A Python-based model was developed to analyze and simulate the experiment's data, including the diffusion of dissolved gases and solutes in claystone pore water, thermodynamic modeling of gas-water-solid phase equilibria, and simulations of chemical equilibria and reaction kinetics. The model accurately reproduces the temporal changes in gas pressure, composition, and solute concentrations measured in situ. The effective diffusion coefficients for dissolved gases in Opalinus Clay derived from the modeling closely match measurements from other experimental studies. The study highlights the importance of accurately describing the temporal variations in hydrogen injection and inflow of formation water for modeling microbially mediated hydrogen consumption in the injection interval.
ENVIRONMENTAL GEOTECHNICS
(2022)
Article
Geochemistry & Geophysics
Benoit Quesnel, Laurent Truche, Michel Cathelineau, Marie-Christine Boiron, Malgorzata Lempart-Drozd, Thomas Rigaudier, Arkadiusz Derkowski, Eric C. Gaucher
Summary: Phyllosilicates can trap or produce hydrogen in the crust through various processes, including dehydrogenation. Thermal treatment of chloritite and talc released H-2 and CO, with hydrogen content up to 7 ppm and a carbon isotope composition suggesting a link to graphite found in the deposit. This study highlights the potential source of H-2 from phyllosilicates and the importance of considering dehydrogenation in the geochemical cycle of hydrogen.
Article
Geochemistry & Geophysics
C. Tichadou, M. Godard, M. Munoz, P. Labaume, A. Vauchez, E. C. Gaucher, S. Calassou
Summary: The study focused on the petrology, mineralogy, and geochemistry of hydrothermally altered peridotites from the North-Western Pyrenean belt, revealing different degrees of serpentinization and reaction paths in the cooling process. The formation of magnetite in these samples was found to be influenced by fluid composition rather than solely by temperature, leading to variations in serpentinization pathways within and among different massifs.
Article
Geochemistry & Geophysics
Jessica Strydom, Jerome Sterpenich, Dragan Grgic, Antonin Richard, Hans G. M. Eggenkamp, Pierre Agrinier, Pascale Louvat, Regine Mosser-Ruck, Patrick Gaire, Eric C. Gaucher
Summary: This study investigates the chemical and halogen isotope evolutions of pore water expelled during clay compaction. The results show significant differences in chemistry and isotope behavior between swelling clay and non-swelling clay. Higher temperature during compaction leads to more freshening of the expelled water. The study suggests that Cl and Br isotopes can be used as tracers to track the origin of low-salinity formation waters in sedimentary basins.
APPLIED GEOCHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Maria Naumenko-Dezes, Wolfram Kloppmann, Michaela Blessing, Raphael Bondu, Eric C. Gaucher, Bernhard Mayer
Summary: This article presents a study that reveals a previously overlooked source of natural gas in shale formations, which is generated by radiolysis of organic matter. The study shows that radiolytic gas can account for a significant portion of natural gas mixtures in major shale gas plays worldwide. Considering radiolytic gas as an additional component in uranium-bearing shale gas formations can lead to a more accurate determination of the origins of natural gas.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Green & Sustainable Science & Technology
Fanny Soetaert, Heike Wanke, Alain Dupuy, Vanessa Lusuekikio, Eric C. Gaucher, Vincent Bordmann, Jean-Marc Fleury, Michel Franceschi
Summary: This study evaluates the quality of springs in northwestern Namibia and proposes solutions for their sustainable use. Despite being in a region impacted by climate change, springs remain an important and sustainable water resource. However, most of the springs lack protective measures, highlighting the need for further conservation efforts.
Article
Geochemistry & Geophysics
N. Lefeuvre, L. Truche, F- Donze, F. Gal, J. Tremosa, R-A Fakoury, S. Calassou, E. C. Gaucher
Summary: This article discusses the energy potential of geological fluids rich in natural hydrogen and calls for the development of an exploration guide that takes into account the deep geological setting. New geochemical and geophysical data reveals the presence of a gas-draining fault along the North Pyrenean Frontal Thrust, and historical well data combined with recent surveys highlight the Triassic salt formations as the most promising trap for hydrogen in the northwestern Pyrenees.
APPLIED GEOCHEMISTRY
(2022)
Article
Geochemistry & Geophysics
Bruno Leclere, Hannelore Derluyn, Eric C. Gaucher, Sylvain Calassou, Joseph Diaz, Jean-Paul Callot, David Gregoire
Summary: This study aims to reproduce geological objects in laboratory conditions and investigate the precipitation of barite in two sedimentary rock samples using a contra diffusive setup. The results show that the barite front is precipitated at different positions in the samples depending on the diffusion of different ions, and the nucleation process is influenced by the pore size and composition.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geosciences, Multidisciplinary
F. Osselin, C. Soulaine, C. Fauguerolles, E. C. Gaucher, B. Scaillet, M. Pichavant
Summary: Enhancing natural subsurface hydrogen production through water injection could play a key role in achieving the low-carbon energy transition and limiting global warming. Replacing current hydrogen production methods with low-carbon options is crucial for hydrogen to become a viable solution.
Article
Nuclear Science & Technology
Jacques De Lamare, Agnes Vinsot, Antoine Pasteau
Summary: This paper discusses measurements of air pressure, relative humidity, temperature, and oxygen molar fraction in a micro-tunnel experiment at the Andra's Meuse/Haute-Marne underground research laboratory. The study reveals that corrosion of steel liners, water evaporation from saturated clay, and leaks between the tunnel excavation and the access drift are the main factors affecting the profiles of relative humidity and oxygen molar fraction. A simple model is used to simulate the oxygen evolution and calculate associated air fluxes, which matches well with experimental data when diffusion-driven leaks are taken into account.
PROGRESS IN NUCLEAR ENERGY
(2022)
Article
Geochemistry & Geophysics
Xavier Mangenot, Hao Xie, Antoine Cremiere, Thomas Giunta, Marvin Lilley, Olivier Sissmann, Victoria Orphan, Arndt Schimmelmann, Eric C. Gaucher, Jean-Pierre Girard, John Eiler
Summary: We present a method for measuring the clumped isotope composition of molecular hydrogen (H2) using a high-resolution mass spectrometer and optimized techniques for sample purification and concentration. The accuracy of the method is validated through comparisons with established methods and measurements of H2 gases at isotopic equilibrium. The study also investigates gas purification methods and demonstrates negligible changes in clumped isotope composition. Furthermore, the method is applied to natural geological samples, revealing the potential of clumped isotope composition in tracking temperatures and biogeochemical processes related to H2.
Article
Geology
D. Laurent, G. Barre, C. Durlet, P. Cartigny, C. Carpentier, G. Paris, P. Collon, J. Pironon, E. C. Gaucher
Summary: This study quantifies the relative influence of microbial and thermochemical processes on sulfuric-acid production in two caves in the French Pyrenees using an innovative approach combining geomorphology with measurements of multiple sulfur, oxygen, and strontium isotopes. The results reveal the origin of sulfate speleothems and provide insights into the percentages of biotic and abiotic sulfuric-acid speleogeneses that have occurred in the caves, highlighting the need for similar studies in other sulfuric-acid caves where microbial activity is typically considered.
Article
Energy & Fuels
F. Osselin, E. C. Gaucher, P. Baldoni-Andrey, W. Kloppmann, B. Mayer
Summary: To analyze the effect of a new gelling agent for hydraulic fracturing, fluid samples from different stages of the operation were collected from a well in Argentina. The samples were analyzed over a period of two years, showing an increase in salinity due to mixing with formation water and a decrease in concentration of trace elements and heavy metals, possibly due to delayed precipitation of barite. This finding suggests a potential option for mitigation and remediation of wastewaters from hydraulic fracturing.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Geosciences, Multidisciplinary
Elodie Muller, Magali Ader, Giovanni Aloisi, Cedric Bougeault, Christophe Durlet, Emmanuelle Vennin, Karim Benzerara, Eric C. Gaucher, Aurelien Virgone, Marco Chavez, Pierre Souquet, Emmanuelle Gerard
Summary: This study investigates the formation of modern carbonate microbialites in the hydrothermal system of Laguna Pastos Grandes in Bolivia, and discovers multiple modes of carbonate precipitation under different physicochemical conditions.