Rockwall erosion by rockfall processes proceed at rates between 0.05 ±0.03 to 14.4 mm a^-1 (Draebing et al., 2022) and are key agents of alpine landscape evolution. Previous studies suggest that frost weathering is a major contributing process to alpine rockwall erosion (Draebing and Mayer, 2021). Frost weathering occurs primarily by frost cracking driven by ice segregation, but our current process understanding is based on studies focusing on high-porosity low-strength rocks. However, rock types forming alpine rockwalls are characterized by crack-dominated porosity and high rock strength, therefore, it is unclear how past findings from low-strength rocks apply in these settings. In this study, we will perform laboratory ice segregation tests on rock samples with different saturation levels and fracture density to quantify their influence on frost cracking efficacy.

We used Wetterstein limestone rock samples in laboratory experiments and exposed rocks to realistic-rockwall freezing conditions while monitoring acoustic emissions as a proxy for cracking. To differentiate triggers of cracking, we modelled ice pressures and thermal stresses. We tested the influence of (i) saturation (low versus full initial saturation), (ii) crack density (0.4 versus 0.6 % rock porosity), and (iii) temperature range (-10 to 0°C) on the efficacy of ice segregation.

(i)  Our data showed that the efficacy of ice segregation is not controlled by initial water content in alpine rocks. These results suggest that water available at depth within alpine rock masses can rapidly travel along fractures to form ice lenses near the rock surface.

 (ii) Crack density has a direct impact on the elastic properties of rocks, which shifts the stress threshold for crack propagation. A fractured rock with high crack density is less prone to ice segregation as its lower brittleness increases the critical fracture toughness.

(iii) Our data revealed temperature patterns promoting ice segregation with highest rates of frost cracking at temperatures between -10 and -7 °C in high strength Wetterstein limestone.

We conclude that frost cracking efficacy in high alpine environments is more impacted by temperatures than by initial rock moisture, which potentially results in more rockfall at colder north- than warmer south-facing rockwalls.

Draebing, D., Mayer, T., Jacobs, B., and McColl, S. T.: Alpine rockwall erosion patterns follow elevation-dependent climate trajectories, Communications Earth & Environment, 3, 21, https://doi.org/10.1038/s43247-022-00348-2, 2022.

Draebing, D., and Mayer, T.: Topographic and geologic controls on frost cracking in Alpine rockwalls, Journal of Geophysical Research: Earth Surface, 126, e2021JF006163, https://doi.org/10.1029/2021JF006163, 2021.

How to cite: Mayer, T., Eppes, M., and Draebing, D.: Quantifying controlling factors of ice segregation in alpine rocks, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5126, https://doi.org/10.5194/egusphere-egu23-5126, 2023.

Brittle creep in rock that results from time-dependent subcritical crack growth often plays a fundamental role in the emergence of precursory phenomena of impending catastrophic events in the upper crust. Laboratory has been used to investigate time-dependent cracking in brittle rocks, and signals of acoustic emission (AE) and X-ray tomography were employed as proxies for damage accumulation, which increase non-linearly towards failure (Heap et al., 2009; Renard et al., 2020). Despite these studies, the evolution of damage in real time and especially the potential impact of strain localization on dynamic critical transition of failure yet are understudied.

We study brittle creep in a dry Herrnholz granite (with an initial porosity of 2.2%) under triaxial stress conditions. The test procedures consisted of (i) confining the sample to P_c =10 MPa and (ii) then applying and holding a differential stress σ_d = 234 MPa. This stress was held constant and a standard creep response was observed exhibiting a clear trimodal behavior that culminated with the formation of a shear fracture and catastrophic failure of the sample. We used the distributed strain sensing (DSS) fiber optic technology to obtain local estimations of strain and calculate volumetric strain on the surface of the sample using an interpolation strategy. During the primary creep phase, deformation mapped with DSS was found to be sparsely distributed in the form of volumetric deformation in general uniform throughout the sample and expressed on the surface. The transient acceleration of creep (creep burst) was only identified in local strain measurements near the final faulting position and occurred during the steady-state creep phase. This clearly indicates that strain began to localize around the ultimate location of fracture, which was also confirmed by the postmortem 3D optical scanning.

Using this better understanding of progressive strain localization, we searched for indications of damage evolution and critical behavior. During the creep phases, changes in certain properties of DSS array were examined for potential precursory signatures. We analyzed the statistics of damage rate and incremental strain and detected a significant breaking of scaling during the creep phase which led to a critical interpretation of fracture. Prior to the critical point, creep bursts correlated with the nucleation and growth of the main fault, which likely indicates the onset of scaling divergence where damage began to self-organize toward failure. These results show that strain localization which drives the fracture development can be captured by DSS technology and the brittle creep processes in Herrnholz granite follow a critical point transition which can be attributed to a self-adjustment of local strains after creep burst.

References:

Heap, M. J., Baud, P., Meredith, P. G., Bell, A. F., & Main, I. G. (2009). Time-dependent brittle creep in Darley Dale sandstone. Journal of Geophysical Research, 114(B7), B07203. https://doi.org/10.1029/2008JB006212

Renard, F., Kandula, N., McBeck, J., & Cordonnier, B. (2020). Creep burst coincident with faulting in marble observed in 4‐D synchrotron X‐ray imaging triaxial compression experiments. Journal of Geophysical Research: Solid Earth, 125, e2020JB020354. https://doi.org/ 10.1029/2020JB020354

How to cite: Chen, H., Selvadurai, P. A., Vasquez, A. S., Bianchi, P., Lei, Q., Madonna, C., and Wiemer, S.: Illumination of Damage and Critical Transition During Time-Dependent Deformation in Herrnholz Granite Using Distributed Strain Sensing, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-16084, https://doi.org/10.5194/egusphere-egu23-16084, 2023.

Deformation bands, or tabular zones of localised strain, are a common manifestation of deformation in upper crustal sedimentary rocks. Any mining or energy-related engineering applications must consider the possibility of reactivating these pre-existing failure planes because doing so can cause seismicity and compartmentalise the reservoir. However, there has only been a small amount of research done on laboratory-induced deformation in rocks with natural deformation features.

On a low porosity bioclastic calcarenite from the Cotiella Basin, Spanish Pyrenees, our current experimental work aims to capture, for the first time to our knowledge, the dominant failure mechanisms during the reactivation of natural deformation bands oriented at different angles to the principal stress direction. At the I12-JEEP beamline at the synchrotron facility of Diamond Light Source, UK, we carried out triaxial compression experiments using a modified version of the Mjolnir cell used by Cartwright-Taylor et al., (2022) to examine how these highly heterogeneous rocks respond to additional mechanical deformation. During the deformation experiments, 4D (time and space) x-ray tomography images (8 m voxel size resolution) were acquired. We tested confining pressures between 10 MPa and 30 MPa.

The mechanical data demonstrate that the existence of natural deformation features within the tested samples weakens the material. For instance, solid samples of the host rock subjected to the same confining pressures had higher peak differential stresses. Additionally, our findings demonstrate that new deformation bands form as their angle, θ, to σ1 increases, while the reactivation of pre-exiting deformation bands in this low porosity carbonate only occurs for dipping angles close to 70^o. The spatio-temporal relationships between the naturally occurring and laboratory-induced deformation bands and fractures were investigated using time-resolved x-ray tomography and Digital Volume Correlation (DVC). Volumetric and shear strain fields were calculated using the SPAM software (Stamati et al., 2020). The orientation of the recently formed failure planes is influenced by the orientation of the pre-existing bands, as well as their width and the presence (or absence) of porosity along their length. Additionally, pre-existing secondary deformation features found in the tested material trigger additional mechanical damage that either promotes the development or deflects the new failure planes.

References

Cartwright-Taylor et al. 2022, Nature Communications 13, 6169, https://doi.org/10.1038/s41467-022-33855-z

Stamati et al. 2020, Journal of Open Source Software, 5(51), 2286, https://doi.org/10.21105/joss.02286

How to cite: Charalampidou, E.-M., Taxopoulou, M.-E., Beaudoin, N., Aubourg, C., Cartwright-Taylor, A., Butler, I., Atwood, R., and Michalik, S.: Failure mechanisms in low-porosity carbonate rocks during the reactivation of deformation bands with various orientations, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9609, https://doi.org/10.5194/egusphere-egu23-9609, 2023.

Rock masses are often criss-crossed by generations of discontinuities, including veins, fractures, and joints. The presence of fractures and joints can increase rock mass permeability and decrease rock mass strength. However, fluid flow within rock masses can result in secondary mineral precipitation within these spaces. Secondary mineralisation can reduce permeability, with important consequences for fluid flow in systems that rely on discontinuity-dominated permeable networks. Here we investigate if variably sealed joints can be reactivated during deformation and the role joint reactivation plays on permeability. We deformed 20 mm in diameter by 40 mm long cores of un-jointed and jointed (variably sealed) bedded sandstones. Samples were cored such that their dominant structural feature (i.e., bedding or joint) was oriented parallel, perpendicular, or at approximately 30° to the sample axis. We find that the permeability of the undeformed samples is sensitive to the presence and orientation of bedding. In jointed samples, well-sealed joints can act as barriers to fluid flow, but partially filled joints neither inhibit nor promote fluid flow with respect to their joint-free counterparts. While all rocks in this study deformed in the brittle regime under triaxial deformation conditions, the location of the experimentally induced fractures depends on the extent to which joints are sealed. The mineralisation that fills well-sealed joints also permeates the surrounding sandstone matrix, locally reducing porosity and forming a cohesive bond between the joint-fill and the host-rock that increases rock strength: experimentally induced fractures do not exploit pre-existing joint surfaces in these samples. By contrast, strain is localised on the joint surface in samples containing partially sealed joints and the strength of these samples is lower than their un-jointed counterparts. The permeability of all samples increased after deformation, but permeability increase was largest in samples with pre-existing, poorly filled joints. We conclude that partially sealed joints act as planes of weakness within rock masses and that their reactivation can result in significant permeability increase. Well-sealed joints, however, may locally increase rock strength and never become reactivated during deformation: consequently, these joints may never re-contribute to the permeability of a rock mass. These observations provide insight into how fluid flow in the crust may evolve, with possible implications for how these systems weather over time.

How to cite: Kushnir, A., Heap, M., Baud, P., Reuschlé, T., and Schmittbuhl, J.: Reactivating sealed joints: rock strength reduction and permeability enhancement … sometimes, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-3676, https://doi.org/10.5194/egusphere-egu23-3676, 2023.

Fractures in rock are ubiquitous; from cold dry planetary bodies to the hottest, wettest climates on Earth, and from km-scale tectonic fractures deep in Earth’s crust to microcracks in surficial rocks. Yet, many of these fractures propagate progressively over geologic timescales, making their development complex and enigmatic. Therefore, to measure how fractures have developed in rocks exposed at Earth’s surface over millennia, and how this consequently changes rock physical properties, we collected ten ~25 cm diameter granitic boulders from two sites in the Eastern Sierra, California, USA. The boulders were deposited on the surface of alluvial terraces and fans during geologically instantaneous glacial and alluvial events at different times since about 148ka BP, then the depositional surfaces were subsequently abandoned. The chronosequences of geomorphic surfaces provide a natural laboratory in which rocks of consistent lithology have been exposed to similar environmental conditions for different lengths of time, allowing us to compare rock property evolution on the order of 0 to 10⁵ years of environmental exposure; an approach that allows us to better understand and characterize mechanical weathering processes, especially long-term changes in rock fracturing. Note that fresh (time-zero) rocks in this study are represented by boulders found within active channels, and that the measured changes in rocks with longer exposure times are interpreted by comparison with the fresh rocks. Focusing only on similarly sized boulders removes any ambiguities in tectonic and exhumation history that might arise in outcrop samples, thus ensuring that rocks from each site have experienced similar stress conditions; namely those restricted to the environment.

We performed laboratory measurements on 10 granitic boulders (four from Lundy Canyon, with exposure ages of ~0 to ~148 ka; six from Shepherd Creek, with exposure ages of ~0 to ~117 ka) to quantify how rock physical properties changed as a function of environmental exposure age. We measured key parameters commonly used as proxies for crack damage, including porosity, compressional wave velocity (Vp), and shear wave velocity (Vs). We hypothesize that changes in crack damage are likely to affect rock mechanical properties, so we also measured tensile strength, uniaxial compressive strength (UCS), and Young’s modulus (E). We find that all measured parameters evolve as a function of exposure age, with systematic increases in porosity, and systematic decreases in Vp, Vs, tensile strength, UCS, and E. For example, porosity increases from 0.5 – 1.0 % in the fresh rock to 2.6 – 3.2 % in the oldest rocks. We interpret these changes as reflecting progressive subcritical crack growth that arises due to ubiquitous, but relatively low magnitude, environmental stresses continuously acting on the boulders, as opposed to differences inherited before their erosion from bedrock.

Apart from demonstrating the importance of environmentally driven cracking in rock weathering, these observations of progressive crack damage accumulation also have significant implications for the interpretation of any measurements made on rocks exposed at Earth’s surface, even if the age of exposure is relatively short compared to the age of the geologic deposit itself.

How to cite: Meredith, P., Yuan, Y., Rasmussen, M., Hofer Apostolidis, K., Nara, Y., Webb, P., Mitchell, T., Xu, T., Keanini, R., Mushkin, A., Shaanan, U., Dahlquist, M., Rinehart, A., and Eppes, M.: Evidence for increase in crack damage in rocks with duration of exposure at Earth’s surface., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7101, https://doi.org/10.5194/egusphere-egu23-7101, 2023.

Previous investigations of the compressive failure of porous rocks under true triaxial compression have focused on the brittle faulting regime. These studies have underscored the dependence of the peak stress state on the interplay of the three principal stresses. In comparison, there is a paucity of systematic investigations of ductile failure under true triaxial compression. In this study we selected Bleurswiller sandstone, which has been extensively investigated in relation to the brittle-ductile transition under conventional triaxial compression at room temperature. Experiments were conducted in Wuhan on water-saturated samples with the size of 100mm×50mm×50mm at the minimum and intermediate principal stresses ranging up to 70 MPa and 170 MPa, respectively. Previous conventional tests have shown that the initial yield points of Bleurswiller sandstone fall on a linear cap relating the differential and mean stresses. Our new data show that initial yielding under true triaxial loading at a fixed Lode angle is also characterized by a Mises effective shear stress that decreases linearly with increasing mean stress, in agreement with the prediction of an elastic-plastic pore collapse model. Subsequent yielding was manifested by various degrees of strain hardening, that would culminate in a spectrum of failure modes (high-angle shear bands, conjugate shear bands, compaction bands, distributed cataclastic flow). The 3D complexity and geometric attributes of these failure modes have been characterized by X-ray CT imaging of the failed samples.   

How to cite: Meng, F., Shi, L., Hall, S., Baud, P., and Wong, T.: Inelastic compaction and failure mode of Bleurswiller sandstone under true triaxial compression, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4110, https://doi.org/10.5194/egusphere-egu23-4110, 2023.

We present a new structural model of the Theistareykir high-temperature geothermal field, located in NE Iceland within a volcanically active rift zone. Various interdisciplinary geoscientific methods are applied and cross-analyzed. We use remote sensing data, structural and geological surface and subsurface mapping, drone surveys, borehole images, seismicity, potential field, and CO₂ surface emissions data. This composite data modelling approach aims to highlight primary fault zones and fractured intervals at the surface by assigning fault types and their spatial orientation. The compiled surface and subsurface datasets were used for 3D fault projections and the delineation of fault-block compartments. Fault plane solutions from earthquakes supported fault property assignments, slip direction, and stress-field orientations. Surface fault segments and fracture intensity maps highlight areas of relay ramping, fault damage, and accommodation zones in between the NW-SE, NE-SW to N-S striking fault systems of the Theistareykir rift segment. The fault systems are intersected by WNW-ESE striking embryonic transfer zones that form boundaries between rift valley graben segments south and within the Theistareykir geothermal field area. These WNW-ESE transfer zones accommodate the differential and oblique opening of the rift zone, which overall follows the right-lateral opening direction of the region south of the Husavik-Flatey transform fault. Our structural model of the Theistareykir geothermal field area is subdivided into six structural domains that form fault block compartments, with varying degrees of faulting and fracturing, reflecting the different quality of hydraulic connectivity across the field.

How to cite: Blischke, A., Hjartardóttir, Á. R., Gudnason, E. Á., Ágústsdóttir, T., Benediktsdóttir, Á., Vilhjálmsson, A. M., Þorsteinsdóttir, U., Einarsson, G. M., Óladóttir, A. A., and Mortensen, A. K.: 3D structural mapping of the Theistareykir geothermal field, NE-Iceland: Fault and fracture connectivity within a volcanically active rift zone., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8009, https://doi.org/10.5194/egusphere-egu23-8009, 2023.

Human intervention in subsurface geoenergy systems, such as fluid injection, can lead to induced seismicity. Particularly in geothermal systems where faults or fractures serve as fluid pathways, fault reactivation is a significant risk. Therefore, we must elucidate under which stress conditions faults become reactivated. The geometry of fault planes evolves as a function of fault displacement. Mature faults (i.e. with 10-100 m displacement) are most likely gouge-filled due to material weathering during movement. This study investigates the Lower Carboniferous system and specifically the Dinantian formation. This specific formation is particularly interesting for deep geothermal energy in the Netherlands, Belgium and Germany but can serve as a proxy for fractured carbonate deep geothermal reservoirs worldwide. The Dinantian carbonates exhibit pre-existing fractures which mainly contribute to rock permeability. However, there is little or no knowledge of the fault geometry and filling material. Subsequently, it is essential to investigate a spectrum of carbonate fault geometries and gouge material to deliver fault stability conditions. 

Here, we aim to experimentally characterise fault strength through all stages of their temporal evolution, from bare rock to highly strained fault gouges at a range of normal stresses. All experiments are performed at room temperature, using de-ionised (DI) water as pore fluid. The bare rock surfaces are gouge-free saw-cut samples, loaded into a Hoek cell embedded in a 500 kN uniaxial loading machine. These experiments are performed at a range of confining pressure from 10 to 50 MPa, corresponding to normal stresses from 60 to 90 MPa and undrained conditions. We determined the critical range of axial, shear and normal stress values per experiment at which fault reactivation was initiated. We used a rotary shear apparatus to increase fault gouge maturity through the shearing of a simulated gouge material in drained conditions. In a single experiment and sample, we changed the normal stress with a protocol of 2-4-6-8-10-8-6-4-2 MPa. For every stress interval, we performed a slide-hold-slide procedure, where the slide-hold times were 10-10-10-100-10-1000-10 sec and the velocity was 20-0-20-0-20-0-20 μm/sec respectively. After each hold time, the reactivation leads to a different peak shear stress. By characterizing the different peak stresses we can quantify the evolution of critical shear stress as a function of fault inactivity time. We used the reactivation stresses for both experimental types to calculate the intercept and angle of the reactivation envelopes in a Mohr-Coulomb context using linear regression, which corresponds to the cohesion and friction coefficient of the laboratory faults. 

Our preliminary results for the rotary shear experiment show that mature carbonate laboratory faults exhibit a cohesion of <1 MPa and friction coefficient up to 0.65 under wet conditions. Moreover, the cohesion of the fault decreases as a function of healing time and the friction coefficient increases. Future plans include the investigation of fluid chemistry on the reactivation envelope. To conclude, we aspire to give insight to the operators on how to safely design the geothermal injection and production schemes accounting for the geomechanical constraints.

How to cite: Kane, E., Pluymakers, A., and Niemeijer, A.: Reactivation envelopes of immature and mature faults of Dinantian carbonates targeted for geothermal energy, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11236, https://doi.org/10.5194/egusphere-egu23-11236, 2023.

We perform laboratory experiments of decametric scale using a novel triplet apparatus (Fig. 1) that allows (a) to reproduce earthquake-like instabilities and (b) to prevent them by active fluid pressure adjustment. The dynamic earthquake events are prevented using high-end, robust stabilizing controllers that stabilize the system even in the absence of knowledge about its friction, elasticity and other complex phenomena that are hard to quantify in practice.

Two scenarios are investigated experimentally. In the first scenario, the system is loaded close to its instability point and then fluid is injected in order to provoke a seismic event. We observe how the controller automatically adjusts the fluid pressure in order to prevent such instabilities and immobilize the system. In the second scenario, the controller adjusts the fluid pressure automatically in order to drive the system in a new stable equilibrium of lower energy in an aseismic manner. Despite the inherent unstable behavior of the system, uncertainties related to friction, elasticity and multiphysics couplings, the earthquake-like events are avoided and controlled. We expect our methodology to inspire earthquake mitigation strategies regarding anthropogenic and/or natural seismicity.

References

[1] Stefanou, I. (2019). Controlling Anthropogenic and Natural Seismicity: Insights From Active Stabilization of the Spring‐Slider Model. Journal of Geophysical Research: Solid Earth, 124(8), 8786–8802. https://doi.org/10.1029/2019JB017847
[2] Tzortzopoulos G., Braun P., Stefanou I. (2021), Absorbent Porous Paper Reveals How Earthquakes Could be Mitigated, Geophysical Research Letters 48. https://doi.org/10.1029/2020GL090792.
[3] Stefanou, I., Tzortzopoulos, G. (2022). Preventing instabilities and inducing controlled, slow-slip in frictionally unstable systems. Journal of Geophysical Research: Solid Earth. https://doi.org/10.1029/2021JB023410
[4] Gutiérrez-Oribio D., Tzortzopoulos G., Stefanou I., Plestan F. (2022). Earthquake Control: An Emerging Application for Robust Control. Theory and Experimental Tests. http://arxiv.org/abs/2203.00296
[5] Papachristos, E., Stefanou, I. (2022), Controlling earthquake-like instabilities using artificial intelligence. http://arxiv.org/abs/2104.13180.
[6] Gutiérrez-Oribio D., Stefanou I., Plestan F. (2022). Passivity-based Control of a Frictional Underactuated Mechanical System: Application to Earthquake Prevention. https://arxiv.org/abs/2207.07181

Fig.1: Experiments of decametric scale using a novel triplet apparatus for preventing earthquake-like instabilities

How to cite: Stefanou, I., Tzortzopoulos, G., Braun, P., and Gutierrez-Oribio, D.: Controlling earthquake-like instabilities in the laboratory, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8589, https://doi.org/10.5194/egusphere-egu23-8589, 2023.

The creation of fractures in boreholes by hydraulic stimulation is of importance for enhancing fluid transport in the context of geothermal reservoirs. Detecting whether a fracture is created and evaluating its capacity to transport fluid are usually performed by locating the acoustic emissions generated during the rock failure and by comparing the hydraulic properties before and after this type of hydraulic stimulation using pumping tests, respectively. However, free oscillations, exerted by rapid changes in pumping parameters, can be used as well to detect the existence of a fracture and to evaluate its permeability. The diagnostic properties of free pressure oscillations are their spectral components, i.e., frequency and damping coefficient. The hydraulic system, which includes technical equipment such as tubes and hoses, and the rock formation, which can be tight or leaky. In a tight system, the free pressure oscillations are attenuated by the viscous interaction of the fluid and the borehole wall and the local coupling of the fluid compression and deformation of the borehole due to the pressure variation. In a leaky system, the attenuation of free pressure oscillations includes fluid exchange between the borehole and the hydraulic conduits of the rock. We developed an analytical solution starting from the dispersion relation of fluid-flow waves in a tight borehole by accounting for the fluid exchange as a modified boundary condition. Deviation of spectral components of observed oscillation from the analytical solution for a tight borehole is an indication that the free pressure oscillations contain information of the hydraulic properties of the penetrated formation. The oscillations typically last for tens of seconds, which allows assessing the success of the stimulation operation on a near-real-time basis. We analyzed the characteristics of free operations recorded in boreholes during several hydraulic stimulation campaigns. We investigated the evolution of the spectral components in the course of the stimulation and with changes in mean injection pressure and obtained transmissivity values that favorably compare to the results of conventional analyses.

How to cite: Jimenez Martinez, V. A. and Renner, J.: Discerning fracturing and constraining hydraulic properties from the characteristics of free pressure oscillations in boreholes, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14681, https://doi.org/10.5194/egusphere-egu23-14681, 2023.