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The primary purpose of underground gas storages is to provide gas for seasonal consumptions or strategic reserve. The periodical operations of gas injection and extraction lead to cyclic loading on the walls and surrounding rocks of gas storages. To investigate the mechanical behaviors of different host rocks in bedded salt deposit, laboratory expe...
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In order to investigate the dynamic compressive characteristics of similar materials in geotechnical model experiment, aluminum split Hopkinson pressure bar apparatus and aluminum sleeve were adopted to conduct impact compressive tests in both uniaxial state and passive confining state under various strain rates. The similar material is a cemented...
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... An unfavourable state causes damage to Underground Storage Caverns (USCs) (Schulze et al. 2001). To ensure the stability, integrity, and safety of the USCs, the macro-mechanical behaviour of rock salt under static, cyclic, fatigue, and creep loading conditions has been studied extensively for the past three decades (Hunsche and Albrecht 1990;Yang et al. 1999;Guo et al. 2012;Liang et al. 2012;Ma et al. 2013;Liu et al. 2014;Chen et al. 2016;Fan et al. 2016;Jiang et al. 2016;Voznesenskii et al. 2017;Singh et al. 2018a;Zhao et al. 2022). Rock salt containing a high halite percentage is a monomineralic crystalline rock. ...
Rock salt under a generalised state of stress is either under the compaction or dilatancy domain. The compaction domain is more favourable for engineering use than the dilatancy domain. This study explores the possible application of the AE technique to identify the favourable or unfavourable state of rock salt. The present study analyses AE data of high-halite percentage Khewra rock salt (> 95% halite mineral) under a quasi-static unconfined compressive strength test. The study employs a unique approach to identifying AE events using a detection function. It has the advantage over a conventional threshold-based method of isolating individual events from the short temporal burst of larger numbers of AE events. The source mechanisms of isolated AE events are identified using the AF–RA method. The results from the analysis conclude that 79% of AE events are due to tensile microcracks, and 21% of AE events are due to shear microcracks. Tensile microcracks release 85% of AE energy. The fracture source of AE events in the case of rock salts is unique, and it differs from the reported literature of other geomaterials where shear microcracks constitute a significant amount of AE events. In the present study, the results of the AF–RA analysis are divided into three stages. The stress path of the three stages is compared with the established dilatancy boundary of rock salts. It is observed for the Khewra rock salt that the stress path of Stage I closer to the compaction domain (favourable, stable) reveals that 42% of AE events originated from shear microcracks, and 58% of AE events originated from tensile microcracks. In the case of Stages II and III, the stress path is in the dilatancy domain (unfavourable, unstable); more than 80% of AE events sources originated from tensile microcracks. The results indicate that in-situ AE monitoring and its AE source mechanism identification can be used to identify rock salts’ favourable and unfavourable conditions.
... An unfavourable state causes damage to Underground Storage Caverns (USCs) (Schulze et al. 2001). To ensure the stability, integrity, and safety of the USCs, the macro-mechanical behaviour of rock salt under static, cyclic, fatigue, and creep loading conditions has been studied extensively for the past three decades (Hunsche and Albrecht 1990;Yang et al. 1999;Guo et al. 2012;Liang et al. 2012;Ma et al. 2013;Liu et al. 2014;Chen et al. 2016;Fan et al. 2016;Jiang et al. 2016;Voznesenskii et al. 2017;Singh et al. 2018a;Zhao et al. 2022). Rock salt containing a high halite percentage is a monomineralic crystalline rock. ...
Rock salt under a generalised state of stress is either under the compaction or dilatancy domain. The compaction domain is more favourable for engineering use than the dilatancy domain. This study explores the possible application of the AE technique to identify the favourable or unfavourable state of rock salt. The present study analyses AE data of high-halite percentage Khewra rock salt (> 95% halite mineral) under a quasi-static unconfined com-pressive strength test. The study employs a unique approach to identifying AE events using a detection function. It has the advantage over a conventional threshold-based method of isolating individual events from the short temporal burst of larger numbers of AE events. The source mechanisms of isolated AE events are identified using the AF-RA method. The results from the analysis conclude that 79% of AE events are due to tensile microcracks, and 21% of AE events are due to shear microcracks. Tensile microcracks release 85% of AE energy. The fracture source of AE events in the case of rock salts is unique, and it differs from the reported literature of other geomaterials where shear microcracks constitute a significant amount of AE events. In the present study, the results of the AF-RA analysis are divided into three stages. The stress path of the three stages is compared with the established dilatancy boundary of rock salts. It is observed for the Khewra rock salt that the stress path of Stage I closer to the compaction domain (favourable, stable) reveals that 42% of AE events originated from shear microcracks, and 58% of AE events originated from tensile microcracks. In the case of Stages II and III, the stress path is in the dilatancy domain (unfavour-able, unstable); more than 80% of AE events sources originated from tensile microcracks. The results indicate that in-situ AE monitoring and its AE source mechanism identification can be used to identify rock salts' favourable and unfavourable conditions.
... Cyclic loading can affect not only elastic properties but also reduce/increase short-term peak strength, modify the C/D boundary, and accentuate tertiary creep. Researchers have shown that the elastic modulus tends to degrade with increasing cycle number, but independent of the stress conditions [248,249]. Viscoplastic deformations such as transient and steady-state creep are highly affected by cyclic loading frequency [248]. The position of the dilation boundary is not affected by cyclic loading, and the creep rate is not significantly affected unless the stress condition is in the dilation region [250]. ...
... However, cyclic loading can reduce the peak strength of salt by up to 30% [246], and the maximum applied stress has a major influence on the fatigue life of salt rock [251,246,248]. Fatigue failure can only occur in the dilation region [80,249,248], and the closer the stress is to the short-term failure boundary, the shorter the fatigue life [251]. The fatigue limit is suggested to be at 75% of compression strength, below which the number of cycles does not influence the accelerated creep [251]. ...
Hydrogen is a promising energy carrier for a low-carbon future energy system, as it can be stored on a megaton scale (equivalent to TWh of energy) in subsurface reservoirs. However, safe and efficient underground hydrogen storage requires a thorough understanding of the geomechanics of the host rock under fluid pressure fluctuations. In this context, we summarize the current state of knowledge regarding geomechanics relevant to carbon dioxide and natural gas storage in salt caverns and depleted reservoirs. We further elaborate on how this knowledge can be applied to underground hydrogen storage. The primary focus lies on the mechanical response of rocks under cyclic hydrogen injection and production, fault reactivation, the impact of hydrogen on rock properties, and other associated risks and challenges. In addition, we discuss wellbore integrity from the perspective of underground hydrogen storage. The paper provides insights into the history of energy storage, laboratory scale experiments, and analytical and simulation studies at the field scale. We also emphasize the current knowledge gaps and the necessity to enhance our understanding of the geomechanical aspects of hydrogen storage. This involves developing predictive models coupled with laboratory scale and field-scale testing, along with benchmarking methodologies.
... The present results suggest that the epoxy resin binding material dispaly elasto-plastic behaviour and has the largest plastic region, indicating that the material undergoes large deformation before ultimate failure happens. This plastic behaviour is somewhat similar to that of salt rocks (Liang et al., 2012). Sample N shows brittle behaviour and failure. ...
Artificial sandstone-like rocks fabricated in the laboratory offer great advantages in controlling their grain size distribution, grain morphology, porosity, and cement content. Synthetic granular rocks offer an efficient way to validate existing analytical models, calibrate numerical models, and perform sensitivity analyses on specific physical parameters. Synthetic sand-stone rocks are manufactured by gluing grains together with a binding material. In this study, we investigated the effect of the three binding materials typically used in synthetic granular rock preparation on mechanical properties and acoustic wave velocities. We used ceramic spherical particles with sizes of 250 μm − 425 μm as grains bonded together by three binding materials, namely i) Epoxy resin, ii) Sodium Silicate with Kaolinite, and iii) Portland cement. While fabricating the core plugs, in each case we kept the relative volume proportion of the binding material with respect to the grains constant. These manufactured sandstone-like dry core plugs were then tested using Autolab-1500 triaxial testing equipment to measure the static mechanical properties and elastic wave velocities at a fixed confining pressure and temperature. Although grain size and distribution, confining pressure, etc., affect the mechanical behavior of rocks, our study focuses on the influence of the binding material alone. Despite the volume fraction of each binding material being the same, they influence the mechanical properties of the rock differently. The sample prepared with epoxy resin exhibited the highest values for Young's modulus, Poisson's ratio, and unconfined compressive strength (UCS) among the three samples. Our findings demonstrate that the selection of binding material plays an important role in controlling the mechanical properties of the rock. Two main reasons account for this behavior: i) the heterogeneous distribution of the binding material within the rock specimen and ii) the effect of the binding material itself on the contact behavior between the grains.
INTRODUCTION
Thermal-Hydro-Mechanical (THM) coupling processes are essential to various engineering and geoscience problems, such as geothermal energy extraction, geological storage of CO2, and nuclear waste disposal. Understanding the interplay between these processes is crucial for predicting the behavior of the Earth's subsurface systems. However, the natural heterogeneity, inhomogeneity, and non-uniformity of geological materials make these processes inherently complex and difficult to model accurately (Tsang, 1991; Rutqvist and Tsang, 2005). To address this challenge, numerical modeling has become a popular tool for simulating THM processes. Nevertheless, robust calibration of numerical models remains a significant obstacle due to the natural variability of rocks (Yoon, 2007).
... Mansouri and Ajalloeian (2018) found that increasing the axial stress level in creep tests resulted in more intensive creep deformation and a greater creep rate. In addition, for the topics related to underground salt caver ns, several researchers have focused on the different stress loading/unloading paths and patterns of cyclic loading on the mechanical properties of salt rock (Fuenkajorn and Phueakphum 2010;Fuenkajorn et al. 2012;Liang et al. 2012;Ma et al. 2013;Khaledi et al. 2016;Han et al. 2021;Wang et al. 2021). Most studies have demonstrated that salt rocks creep easily and dissolve, and the dissolution rate and deformation ability are more or less related to the ambient temperature, confining pressure, impurities, and other factors. ...
This study aims to investigate the potential factors affecting hydraulic fracturing of inter-salt oil shale reservoirs in the Qianjiang Depression, China. Using the inter-salt shale samples, the re-crystallization seepage tests, rock mechanical tests under high temperature and pressure, salt rock creep tests, and direct shear tests were conducted. The testing results suggest several major factors that affect hydraulic fracturing effects in the end. First, the seepage of reservoir and fracturing fluid through hydraulic fractures leads to salt dissolution and crystallization, reducing the effective seepage area of fractures. Second, the salt crystal may block the pore throats or micro fractures after brine invades the shale, decreasing the overall permeability. Third, the low strength and obvious plasticity of inter-salt shale and the strong creep characteristics of salt rock raise difficulties for proppant to effectively support fracture walls, thereby sharply narrowing the hydraulic fracture width. Lastly, the weak interfaces (bedding planes and lithology interfaces) in inter-salt oil shale reservoirs restrict the height of hydraulic fractures, resulting in the disconnection of seepage channels between multiple inter-salt shale reservoirs. Thus, several factors together reduce reservoir permeability, weaken the fluid flow capacity in the fracture, narrow the fracture width, and limit the effective stimulation volume, resulting in weaken the effect hydraulic fracturing.
... The identification of these ingredients can be used in a wide range of applications not only in the context of the solubility of individual minerals, but also the mechanical properties of rock salt which are also very important. The mechanical properties of the rock salt depend not only on its individual mineral composition but also depend on the crystal structure of each mineral, content and distribution of impurities or fluid inclusion [65][66][67][68]. ...
The paper presents research on chloride minerals of natural origin from Kłodawa (Po-land), i.e., colorless, blue and purple halite as well as colorless sylvite. Selected samples of minerals were studied by chemical analysis (ICP-OES, ICP-MS, titration methods) and crystallographic measurements. Then, for the tested halides, research was carried out using far-infrared spectros-copy. Spectroscopic studies confirmed the simple way of distinguishing NaCl and KCl minerals using far-infrared spectroscopy, known in the literature. The novelty is that the article presents for the first time the experimental far infrared spectra of natural blue and purple halite. It was observed that the blue (178 cm −1) and purple (176 cm −1) halites have the strongest infrared band slightly shifted towards higher wavenumbers compared to colorless halite (174 cm −1). As part of the work, the infrared spectra of the crystal structure models of sodium and potassium chloride were calculated for the first time using the density functional theory (with the B3LYP functional and the 6-31G* basis set, 125-atom model). The proposed approach can be used not only as a powerful method differentiating NaCl and KCl minerals, but it can also help with understanding of different defects in crystal lattices for naturally occurring halides and crystals of other minerals.
... Considering the importance of salt caprocks not only as part of the petroleum system but also as geological barriers for underground nuclear waste disposal and CO 2 sequestration, various physical experiments and numerical modeling techniques have been used to assess their integrity (Liang et al., 2007(Liang et al., , 2012Shukla et al., 2010;Orlic and Wassing, 2012;Popp et al., 2012;Knauth and Minkley, 2014;Minkley et al., 2015;Firme et al., 2018;Wu et al., 2020;Kolditz et al., 2021). Although these efforts, the failure of salt rock integrity has rarely been reported with direct evidence to explain the exact geological conditions (pressure, temperature, time) when ancient fluids did breakthrough. ...
Salt rocks are widely distributed in the Paleogene strata of the Dongpu Depression, China, as major caprocks of the Shahejie Formation. Previous studies have suggested that the decline of formation pressure during the Dongying movement is accompanied by petroleum leakage, but they lack any direct evidence of failed integrity of the salt caprocks. Therefore, fluid inclusion analysis under both incident ultraviolet (UV) and transmitted light (TR) modes on halite samples were conducted in this study, supported by basin and fluid inclusion PVTX modeling to prove lack of integrity in the caprock, periodically. Our observation showed that various types of hydrocarbon inclusions exist in halite crystals, revealing multi-stage fracturing and healing processes inside the salt caprocks. Coupling the PVTX and basin modeling results, revealed that oil inclusions were trapped at around 6.6 Ma during the secondary hydrocarbon generation of the source rocks. Moreover, salt caprocks failed due to the overpressure that was formed during hydrocarbon generation. This was exacerbated by the following uplifting which ultimately led to the present-day normal reservoir pressure in the sampled depth. In addition, the fluorescence of oil inclusions in the same fracture gradually changed from orange to blue. This proved that analyzing the thermal maturity of trapped hydrocarbons within the inclusions, solely based on the fluorescence color, could be misleading and other submicron scale analytical methods should be employed to examine the inclusions. Overall, this study enabled us to investigate the caprock integrity via optical methods, which can eventually help us to avoid regions where hydrocarbon is lost vs. prolific areas in the formation understudy.
... BST has been tested in the literature under uniaxial and confined conditions (Haimson 1978(Haimson , 1973Handin et al. 1963;Khan et al. 1991), but most of the tests performed were monotonic or targeted the fatigue life rather than damage or plasticity quantification. Cyclic experimental work available in the literature on rocks and rock-like materials in the majority of cases are uniaxial or dynamic tests (Lei et al. 2018;Liang et al. 2012;Lin et al. 2018;Liu et al. 2016;Liu and Dai 2021;Zhao et al. 2018). Many researchers applied triaxial cyclic loading on different materials, such as marble (Yang et al. 2017), granite (Martin 1997;Tkalich et al. 2016;Zhang et al. 2018), and dolomite (Li et al. 2019). ...
This work presents indirect tensile tests and uniaxial and triaxial monotonic and cyclic compression tests of Berea sandstone (BST) under different levels of confining pressure (CP) where the axial and lateral strains are measured in addition to the axial stress. Based on these experiments, the influence of the CP on the mechanical behavior and the damage mechanics of BST is investigated. Results reveal a strong influence of the applied CP on the strength of the material, where BST switches from brittle to ductile due to the presence of the CP. Damage-controlled tests are exploited to quantify the evolution of plasticity and damage as a function of the applied axial load, as well as the CP level. Experimental analysis imparts damage and plasticity rates with respect to the applied axial load to get lower as the CP increases. To the authors' best knowledge, very little work has been conducted on carefully quantifying plasticity and damage of rocks, especially using cyclic loading at high confinements. The proposed experimental methodology in this work of damage and plasticity quantification delivers a baseline blueprint to refine triaxial experimental data for the sake of development and accurate calibration of advanced constitutive models.
... During the operational activities of salt caverns for gas storage use, the fluctuation of injection and extraction of gas can have implications in the cavern stability Bérest et al., , 2006Huang and Xiong, 2011;Wang et al., 2013;Xiong et al., 2015), like micro-fracking with an associated permeability increase. can have a more brittle response in comparison of halite after a certain number of cycles (Liang et al., 2012). The studies of Liang et al. (2012) demonstrates that other lithotypes that can be presented as interlayers in rock salt formation respond to deformation differently compared to pure salt samples, under cyclic loading conditions. ...
... can have a more brittle response in comparison of halite after a certain number of cycles (Liang et al., 2012). The studies of Liang et al. (2012) demonstrates that other lithotypes that can be presented as interlayers in rock salt formation respond to deformation differently compared to pure salt samples, under cyclic loading conditions. However, further reaserch is needed to analyse rock salt with different second phase content to better understand how different secondary mineralogy affects elastic and physical rock properties before rock failure. ...
... When the internal pressure increased, the velocity of wall closure inside the cavern decreased, and the differential deformation between mudstone and salt rock was smaller. Related to the injection cycle of gas in salt caverns, Liang et al. (2012) supports that a substantial range of strain rates in gas storage exist, where the higher values are obtained during gas withdrawal, for consumption (and lower during gas injection for storage), also known as "stress fluctuation". The authors confirm that this "stress fluctuation" phenomenon should be investigated further from a microstructural deformation point of view. ...
The use of caverns in rock salt for Underground Gas Storage (UGS) and Compressed Air Energy Storage (CAES) have been identified as a strategic option to meet seasonal energy demand fluctuations in the electricity grid. More recently, the Department for Business, Energy and Industrial Strategy (BEIS) presented for the UK Clean Growth strategy a plan to also integrate rock salt caverns as a storage solution for co-located carbon capture, utilisation and storage (CCUS) and hydrogen production. The creation of caverns in halite formations and the operational activities of gas injection and withdrawal occurring under lithostatic pressure are known to lead to local deviatoric stresses, resulting in rock salt creep deformation. Additionally, periodic injection-production activities in response to seasonal temperature changes and associated gas consumption imply regular fluctuation of both mechanical and thermal stresses in salt caverns. Rock salt is mainly composed of halite and has low i) creep strength, ii) porosity, iii) permeability, and iv) density, making it a very good seal rock to store gas. It also typically contains secondary mineral phases (e.g. anhydrite, polyhalite, carnallite, kieserite), as well as fluids trapped in inclusions in the halite crystals, at halite grain boundaries, or in pores. This presence of other minerals besides halite, or other rock layers between the rock salt formations at a range of scales, can have significant effects on the micro and macro-mechanical properties due to their different rheological behaviours, notably weakening the rock salt under high-stress conditions. This project investigates the impact of the secondary mineral phase content on the rock salt mechanical behaviour under cyclic loading conditions. A series of cyclic mechanical loading experiments, at two different ranges of cyclic mechanical load, have been performed on different rock salt samples with different types and amounts of second phase minerals content. In the first set of tests, different confining pressures of 12, 25 and 45 MPa and different temperatures, of 22-25, 55 and 75ºC, have been applied whilst the axial stress was cycled between 4.5 and 7.5 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles). In the second set of experiments, the axial stress was cycled between 6 and 20 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles) and confining pressures of 25 and 45MPa and temperatures of 22-25, 55 and 75ºC. Thin sections of each sample's microstructures, before and after mechanical deformation, were analysed by transmitted light microscopy and Scanning Electron Microscopy (SEM) to identify the micro-mechanisms and early damage induced by the cyclic loading conditions. The results demonstrate that high second phase content such as anhydrite layering operates as a strength weakening agent by displaying larger brittle deformation features in comparison to samples with a lower content in anhydrite, polyhalite or clay as second phase content. This rheological behaviour is further exacerbated by the cycling mechanical conditions and recorded by a marked step on Young's modulus and Poisson's ratio value evolution. The microstructure analysis reveals how halite grains accommodate most of the deformation induced by the cyclic mechanical loading conditions through brittle deformation with micro-fracturing network development. Other structures from different deformation mechanisms are also discussed. Two types of new porosity are observed: i) pores around isolated crystals of second phase minerals as a result of grain rotation under cyclic mechanical deformation, and ii) micro-cracks in areas with a high concentration of secondary minerals (such as anhydrite, polyhalite, carnallite or kieserite). This porosity change has strong implications for both the mechanical behaviour of the material and its potential permeability.
... If applied stress is lower than the strength peaks and elastic limit, dilation is not reached. For underground gas storage, rock fails at 65% -70% of the peak strength under monotonic loading (Liang et al., 2012). So dynamic fatigue induces microcracking of the rock salt, and leakage risk increases (Liu et al., 2014). ...
... Gloyna & Reynolds, 1961;Hatzor & Heyman, 1997;Liang et al., 2007Liang et al., , 2012Muhammad, 2015).On microscale, the secondary mineral deposition of anhydrite, potash, polyhalite and many other present especially in bedded salt behave anisotropically when mechanically loaded(Schulze et al., 2001).On the other hand, damaged samples are highly anisotropic due to orientation of microfractures(Gloyna & Reynolds, 1961;Jockwer & Wieczorek, 2008;Muhammad, 2015). ...
... It's calculated as the slope gradient of linear segment of each cycle(Liu et al., 2014). The elastic modulus of the first cycle at a low level of stress corresponds to the intact material damage state(Lemaitre, 1985;Liang et al., 2012). However, this variable conceals the internal plastic strain due to the visco-elastoplastic behavior of salt. ...
Hydrogen produced from water electrolysis appears to be the best candidate for large- scale geological storage to cover the intermittency of renewable energy. It can be stored either in salt caverns or in porous rocks like saline aquifers and depleted oil and gas reservoirs. This thesis proposes an evaluation of the risk of gas leakage in the case of salt cavities and the risk of biogeochemical alteration of the gas stock in the case of porous reservoir rocks. Rock salt is a polycrystalline material with very low intrinsic permeability in undisturbed zones (around 10-21m2). It sealing capacity is due to the specific features of salt mechanical behavior and gas flow in such unconventional reservoirs (Klinkenberg effect). Deviatoric loading under low confining pressure (1MPa) induces a moderate increase in gas permeability from the dilatancy threshold due to microcracking disturbing the impermeability. So, understanding the complex relationship between permeability evolution and the mechanical and thermal solicitations is important to survey any possible risk of leakage. So, we performed a complete set of laboratory experiments on a rock salt specimen (MDPA in the East region of France). The porosity of the studied rock salt is very low (~1%) and the initial permeability varies over 4.5 orders of magnitude. Klinkenberg effect is only observed for the less damaged samples. The poroelastic coupling is almost negligible. Deviatoric loading under low confining pressure (1MPa) induces a moderate increase in gas permeability from the dilatancy threshold due to microcracking. Measurement of ultrasonic wave velocities during uniaxial compression showed an almost irreversible closure of pre-existing microcracks and the opening of axial microcracks that are perpendicular and parallel to the stress direction allowing a precise determination of the dilatancy threshold. Under higher confining pressure (5MPa), the material becomes fully plastic which practically eliminates damage. Under hydrostatic loading, gas permeability decreases because of the self-healing process. All these results give strong confidence in that underground hydrogen storage in salt caverns is the safest solution. In the case of porous reservoir rocks, hydrogen injection can induce geochemical redox reactions between the fluids and minerals and unwanted consumption of hydrogen stock catalyzed by microorganisms tolerating extreme conditions of deep saline aquifers and reservoirs.To study these phenomena, we developed a new experimental device to simulate the biochemical activity under extreme conditions (T=35°C, PH2=50bar, Pconfinement=200bar). The outflowing gas was automatically sampled with a HP-LP valve and the concentration was measured with a micro-gas chromatograph to quantify any change due to hydrogen bio-consumption. We chose to work on the Vosges sandstone where we incubate the Shewanella putrefaciens bacteria that reduce iron in the presence of hydrogen to produce energy. Its metabolism and performance as hydrogenotrophic bacteria were first tested in batch conditions on a rock powder. Results showed that this type of bacteria can reduce the iron present in the medium using endogenous sources of electrons first then hydrogen in the medium but preferentially dissolved hydrogen. Under triaxial conditions, the bacterial activity doesn’t seem to have a significant impact, whatever the initial hydrogen concentration (70% or 5%) and the sampling frequency (one or three days). Many hypotheses are proposed to explain the observed differences between batch and triaxial conditions: the scarcity of dissolved hydrogen in residual water, the low exchange surface for biogeochemical reactions in the case of solid core samples, and the slow kinetics of hydrogen consumption by S. Despite the remaining uncertainties related to our experiments, our preliminary results suggest that the underground storage of pure hydrogen in porous reservoir rocks is not severely threatened by [...]
