Articles | Volume 13, issue 10 
            
                
                    
            
            
            https://doi.org/10.5194/se-13-1607-2022
                    © Author(s) 2022. 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-13-1607-2022
                    © Author(s) 2022. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
Shear zone evolution and the path of earthquake rupture
                                            Department of Earth & Planetary Sciences, McGill University, 3450 University St., Montréal, QC H3A 0E8, Canada
                                        
                                    
                                            now at: Department of Earth Sciences, Simon Fraser University, 8888 University Dr, Burnaby, BC V5A 1S6, Canada
                                        
                                    Christie D. Rowe
                                            Department of Earth & Planetary Sciences, McGill University, 3450 University St., Montréal, QC H3A 0E8, Canada
                                        
                                    James D. Kirkpatrick
                                            Department of Earth & Planetary Sciences, McGill University, 3450 University St., Montréal, QC H3A 0E8, Canada
                                        
                                    Related subject area
            Subject area: Tectonic plate interactions, magma genesis, and lithosphere deformation at all scales | Editorial team: Structural geology and tectonics, paleoseismology, rock physics, experimental deformation | Discipline: Structural geology
            
                    
                        
                            
                            
                                     
                                Driven magmatism and crustal thinning of coastal southern China in response to subduction
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Selection and characterization of the target fault for fluid-induced activation and earthquake rupture experiments
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Naturally fractured reservoir characterisation in heterogeneous sandstones: insight for uranium in situ recovery (Imouraren, Niger)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Influence of water on crystallographic preferred orientation patterns in a naturally-deformed quartzite
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Multiscalar 3D temporal structural characterisation of Smøla island, mid-Norwegian passive margin: an analogue for unravelling the tectonic history of offshore basement highs
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Localized shear versus distributed strain accumulation as shear-accommodation mechanisms in ductile shear zones: Constraining their dictating factors
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Impact of faults on the remote stress state
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Subduction plate interface shear stress associated with rapid subduction at deep slow earthquake depths: example from the Sanbagawa belt, southwestern Japan
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Multiple phase rifting and subsequent inversion in the West Netherlands Basin: implications for geothermal reservoir characterization
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Analogue modelling of basin inversion: implications for the Araripe Basin (Brazil)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Geomorphic expressions of active rifting reflect the role of structural inheritance: A new model for the evolution of the Shanxi Rift, North China
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Natural fracture patterns at Swift Reservoir anticline, NW Montana: the influence of structural position and lithology from multiple observation scales
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Rapid hydration and weakening of anhydrite under stress: implications for natural hydration in the Earth's crust and mantle
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Analogue experiments on releasing and restraining bends and their application to the study of the Barents Shear Margin
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Structural framework and timing of the Pahtohavare Cu ± Au deposits, Kiruna mining district, Sweden
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Does the syn- versus post-rift thickness ratio have an impact on the inversion-related structural style?
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Inversion of accommodation zones in salt-bearing extensional systems: insights from analog modeling
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Structural control of inherited salt structures during inversion of a domino basement-fault system from an analogue modelling approach
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Kinematics and time-resolved evolution of the main thrust-sense shear zone in the Eo-Alpine orogenic wedge (the Vinschgau Shear Zone, eastern Alps)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Role of inheritance during tectonic inversion of a rift system in basement-involved to salt-decoupled transition: analogue modelling and application to the Pyrenean–Biscay system
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Water release and homogenization by dynamic recrystallization of quartz
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Hydrothermal activity of the Lake Abhe geothermal field (Djibouti): Structural controls and paths for further exploration
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Time-dependent frictional properties of granular materials used in analogue modelling: implications for mimicking fault healing during reactivation and inversion
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Large grain-size-dependent rheology contrasts of halite at low differential stress: evidence from microstructural study of naturally deformed gneissic Zechstein 2 rock salt (Kristallbrockensalz) from the northern Netherlands
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Analogue modelling of the inversion of multiple extensional basins in foreland fold-and-thrust belts
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                A contribution to the quantification of crustal shortening and kinematics of deformation across the Western Andes ( ∼ 20–22° S)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Rift thermal inheritance in the SW Alps (France): insights from RSCM thermometry and 1D thermal numerical modelling
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                The Luangwa Rift Active Fault Database and fault reactivation along the southwestern branch of the East African Rift
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Clustering has a meaning: optimization of angular similarity to detect 3D geometric anomalies in geological terrains
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Mechanical compaction mechanisms in the input sediments of the Sumatra subduction complex – insights from microstructural analysis of cores from IODP Expedition 362
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Detecting micro fractures: a comprehensive comparison of conventional and machine-learning-based segmentation methods
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Multiscale lineament analysis and permeability heterogeneity of fractured crystalline basement blocks
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Structural characterization and K–Ar illite dating of reactivated, complex and heterogeneous fault zones: lessons from the Zuccale Fault, Northern Apennines
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                How do differences in interpreting seismic images affect estimates of geological slip rates?
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Progressive veining during peridotite carbonation: insights from listvenites in Hole BT1B, Samail ophiolite (Oman)
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Tectonic evolution of the Indio Hills segment of the San Andreas fault in southern California, southwestern USA
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Structural diagenesis in ultra-deep tight sandstones in the Kuqa Depression, Tarim Basin, China
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Variscan structures and their control on latest to post-Variscan basin architecture: insights from the westernmost Bohemian Massif and southeastern Germany
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Multi-disciplinary characterizations of the BedrettoLab – a new underground geoscience research facility
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Biotite supports long-range diffusive transport in dissolution–precipitation creep in halite through small porosity fluctuations
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                De-risking the energy transition by quantifying the uncertainties in fault stability
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Virtual field trip to the Esla Nappe (Cantabrian Zone, NW Spain): delivering traditional geological mapping skills remotely using real data
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Marine forearc structure of eastern Java and its role in the 1994 Java tsunami earthquake
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Roughness of fracture surfaces in numerical models and laboratory experiments
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Impact of basement thrust faults on low-angle normal faults and rift basin evolution: a case study in the Enping sag, Pearl River Basin
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Evidence for and significance of the Late Cretaceous Asteroussia event in the Gondwanan Ios basement terranes
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Investigating spatial heterogeneity within fracture networks using hierarchical clustering and graph distance metrics
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Dating folding beyond folding, from layer-parallel shortening to fold tightening, using mesostructures: lessons from the Apennines, Pyrenees, and Rocky Mountains
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Deformation-enhanced diagenesis and bacterial proliferation in the Nankai accretionary prism
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Rheological stratification in impure rock salt during long-term creep: morphology, microstructure, and numerical models of multilayer folds in the Ocnele Mari salt mine, Romania
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
            
        
        Jinbao Su, Wenbin Zhu, and Guangwei Li
                                    Solid Earth, 15, 1133–1141, https://doi.org/10.5194/se-15-1133-2024, https://doi.org/10.5194/se-15-1133-2024, 2024
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                                                The late Mesozoic igneous rocks in the South China Block exhibit flare-ups and lulls, which form in compressional or extensional backgrounds. The ascending of magma forms a mush-like head and decreases crustal thickness. The presence of faults and pre-existing magmas will accelerate emplacement of underplating magma. The magmatism at different times may be formed under similar subduction conditions, and the boundary compression forces will delay magma ascent.
                                            
                                            
                                        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.
                                            
                                            
                                        Maxime Jamet, Gregory Ballas, Roger Soliva, Olivier Gerbeaud, Thierry Lefebvre, Christine Leredde, and Didier Loggia
                                    Solid Earth, 15, 895–920, https://doi.org/10.5194/se-15-895-2024, https://doi.org/10.5194/se-15-895-2024, 2024
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                                                This study characterizes the Tchirezrine II sandstone reservoir in northern Niger. Crucial for potential uranium in situ recovery (ISR), our multifaceted approach reveals (i) a network of homogeneously distributed orthogonal structures, (ii) the impact of clustered E–W fault structures on anisotropic fluid flow, and (iii) local changes in the matrix behaviour of the reservoir as a function of the density and nature of the deformation structure.
                                            
                                            
                                        Jeffrey M. Rahl, Brendan Moehringer, Kenneth S. Befus, and John S. Singleton
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-1567, https://doi.org/10.5194/egusphere-2024-1567, 2024
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                                                At the high temperatures present in the deeper crust, minerals such as quartz can flow much like silly putty. The detailed mechanisms of how atoms are reorganized depends upon several factors, such as the temperature and the rate of which the mineral changes shape. We present observations from a naturally-deformed rock showing that the amount of water present also influences the type of deformation in quartz, with implications for geological interpretations.
                                            
                                            
                                        Matthew S. Hodge, Guri Venvik, Jochen Knies, Roelant van der Lelij, Jasmin Schönenberger, Øystein Nordgulen, Marco Brönner, Aziz Nasuti, and Giulio Viola
                                    Solid Earth, 15, 589–615, https://doi.org/10.5194/se-15-589-2024, https://doi.org/10.5194/se-15-589-2024, 2024
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                                                Smøla island, in the mid-Norwegian margin, has complex fracture and fault patterns resulting from tectonic activity. This study uses a multiple-method approach to unravel Smøla's tectonic history. We found five different phases of deformation related to various fracture geometries and minerals dating back hundreds of millions of years. 3D models of these features visualise these structures in space. This approach may help us to understand offshore oil and gas reservoirs hosted in the basement.
                                            
                                            
                                        Pramit Chatterjee, Arnab Roy, and Nibir Mandal
                                        EGUsphere, https://doi.org/10.5194/egusphere-2024-1077, https://doi.org/10.5194/egusphere-2024-1077, 2024
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                                                Understanding the strain accumulation processes in ductile shear zones is essential to explain the failure mechanisms at great crustal depths. This study explores the rheological and kinematic factors determining the varying modes of shear accommodation in natural shear zones. Numerical simulations suggest that an interplay of the following parameters: initial bulk viscosity, bulk shear rate, and internal cohesion governs the dominance of one accommodation mechanism over the other.
                                            
                                            
                                        Karsten Reiter, Oliver Heidbach, and Moritz O. Ziegler
                                    Solid Earth, 15, 305–327, https://doi.org/10.5194/se-15-305-2024, https://doi.org/10.5194/se-15-305-2024, 2024
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                                                It is generally assumed that faults have an influence on the stress state of the Earth’s crust. It is questionable whether this influence is still present far away from a fault. Simple numerical models were used to investigate the extent of the influence of faults on the stress state. Several models with different fault representations were investigated. The stress fluctuations further away from the fault (> 1 km) are very small.
                                            
                                            
                                        Yukinojo Koyama, Simon R. Wallis, and Takayoshi Nagaya
                                    Solid Earth, 15, 143–166, https://doi.org/10.5194/se-15-143-2024, https://doi.org/10.5194/se-15-143-2024, 2024
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                                                Stress along a subduction plate boundary is important for understanding subduction phenomena such as earthquakes. We estimated paleo-stress using quartz recrystallized grain size combined with deformation temperature and P–T paths of exhumed rocks. The obtained results show differential stresses of 30.8–82.7 MPa consistent over depths of 17–27 km in the paleo-subduction boundary. The obtained stress may represent the initial conditions under which slow earthquakes nucleated in the same domain.
                                            
                                            
                                        Annelotte Weert, Kei Ogata, Francesco Vinci, Coen Leo, Giovanni Bertotti, Jerome Amory, and Stefano Tavani
                                    Solid Earth, 15, 121–141, https://doi.org/10.5194/se-15-121-2024, https://doi.org/10.5194/se-15-121-2024, 2024
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                                                On the road to a sustainable planet, geothermal energy is considered one of the main substitutes when it comes to heating. The geological history of an area can have a major influence on the application of these geothermal systems, as demonstrated in the West Netherlands Basin. Here, multiple episodes of rifting and subsequent basin inversion have controlled the distribution of the reservoir rocks, thus influencing the locations where geothermal energy can be exploited.
                                            
                                            
                                        Pâmela C. Richetti, Frank Zwaan, Guido Schreurs, Renata S. Schmitt, and Timothy C. Schmid
                                    Solid Earth, 14, 1245–1266, https://doi.org/10.5194/se-14-1245-2023, https://doi.org/10.5194/se-14-1245-2023, 2023
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                                                The Araripe Basin in NE Brazil was originally formed during Cretaceous times, as South America and Africa broke up. The basin is an important analogue to offshore South Atlantic break-up basins; its sediments were uplifted and are now found at 1000 m height, allowing for studies thereof, but the cause of the uplift remains debated. Here we ran a series of tectonic laboratory experiments that show how a specific plate tectonic configuration can explain the evolution of the Araripe Basin.
                                            
                                            
                                        Malte Froemchen, Ken J. W. McCaffrey, Mark B. Allen, Jeroen van Hunen, Thomas B. Phillips, and Yueren Xu
                                        EGUsphere, https://doi.org/10.5194/egusphere-2023-2563, https://doi.org/10.5194/egusphere-2023-2563, 2023
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                                                The Shanxi Rift is a young active rift in North China that formed superimposed on a Proterozoic orogen. The impact of these structures on the active rift faults is poorly constrained. Here we quantify the landscape response to active faulting and compare these to published maps of inherited structures. We find that inherited structures played an important role in the segmentation of the Shanxi Rift and in the development of Rift Interaction Zones, the most active regions of the Shanxi Rift.
                                            
                                            
                                        Adam J. Cawood, Hannah Watkins, Clare E. Bond, Marian J. Warren, and Mark A. Cooper
                                    Solid Earth, 14, 1005–1030, https://doi.org/10.5194/se-14-1005-2023, https://doi.org/10.5194/se-14-1005-2023, 2023
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                                                Here we test conceptual models of fracture development by investigating fractures across multiple scales. We find that most fractures increase in abundance towards the fold hinge, and we interpret these as being fold related. Other fractures at the site show inconsistent orientations and are unrelated to fold formation. Our results show that predicting fracture patterns requires the consideration of multiple geologic variables.
                                            
                                            
                                        Johanna Heeb, David Healy, Nicholas E. Timms, and Enrique Gomez-Rivas
                                    Solid Earth, 14, 985–1003, https://doi.org/10.5194/se-14-985-2023, https://doi.org/10.5194/se-14-985-2023, 2023
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                                                Hydration of rocks is a key process in the Earth’s crust and mantle that is accompanied by changes in physical traits and mechanical behaviour of rocks. This study assesses the influence of stress on hydration reaction kinetics and mechanics in experiments on anhydrite. We show that hydration occurs readily under stress and results in localized hydration along fractures and mechanic weakening. New gypsum growth is selective and depends on the stress field and host anhydrite crystal orientation.
                                            
                                            
                                        Roy Helge Gabrielsen, Panagiotis Athanasios Giannenas, Dimitrios Sokoutis, Ernst Willingshofer, Muhammad Hassaan, and Jan Inge Faleide
                                    Solid Earth, 14, 961–983, https://doi.org/10.5194/se-14-961-2023, https://doi.org/10.5194/se-14-961-2023, 2023
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                                                The Barents Shear Margin defines the border between the relatively shallow Barents Sea that is situated on a continental plate and the deep ocean. This margin's evolution history was probably influenced by plate tectonic reorganizations. From scaled experiments, we deduced several types of structures (faults, folds, and sedimentary basins) that help us to improve the understanding of the history of the opening of the North Atlantic.
                                            
                                            
                                        Leslie Logan, Ervin Veress, Joel B. H. Andersson, Olof Martinsson, and Tobias E. Bauer
                                    Solid Earth, 14, 763–784, https://doi.org/10.5194/se-14-763-2023, https://doi.org/10.5194/se-14-763-2023, 2023
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                                                The Pahtohavare Cu ± Au deposits in the Kiruna mining district have a dubious timing of formation and have not been contextualized within an up-to-date tectonic framework. Structural mapping was carried out to reveal that the deposits are hosted in brittle structures that cut a noncylindrical, SE-plunging anticline constrained to have formed during the late-Svecokarelian orogeny. These results show that Cu ± Au  mineralization formed more than ca. 80 Myr after iron oxide–apatite mineralization.
                                            
                                            
                                        Alexandra Tamas, Dan M. Tamas, Gabor Tari, Csaba Krezsek, Alexandru Lapadat, and Zsolt Schleder
                                    Solid Earth, 14, 741–761, https://doi.org/10.5194/se-14-741-2023, https://doi.org/10.5194/se-14-741-2023, 2023
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                                                Tectonic processes are complex and often difficult to understand due to the limitations of surface or subsurface data. One such process is inversion tectonics, which means that an area initially developed in an extension (such as the opening of an ocean) is reversed to compression (the process leading to mountain building). In this research, we use a laboratory method (analogue modelling), and with the help of a sandbox, we try to better understand structures (folds/faults) related to inversion.
                                            
                                            
                                        Elizabeth Parker Wilson, Pablo Granado, Pablo Santolaria, Oriol Ferrer, and Josep Anton Muñoz
                                    Solid Earth, 14, 709–739, https://doi.org/10.5194/se-14-709-2023, https://doi.org/10.5194/se-14-709-2023, 2023
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                                                This work focuses on the control of accommodation zones on extensional and subsequent inversion in salt-detached domains using sandbox analogue models. During extension, the transfer zone acts as a pathway for the movement of salt, changing the expected geometries. When inverted, the salt layer and syn-inversion sedimentation control the deformation style in the salt-detached cover system. Three natural cases are compared to the model results and show similar inversion geometries.
                                            
                                            
                                        Oriol Ferrer, Eloi Carola, and Ken McClay
                                    Solid Earth, 14, 571–589, https://doi.org/10.5194/se-14-571-2023, https://doi.org/10.5194/se-14-571-2023, 2023
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                                                Using an experimental approach based on scaled sandbox models, this work aims to understand how salt above different rotational fault blocks influences the cover geometry and evolution, first during extension and then during inversion. The results show that inherited salt structures constrain contractional deformation. We show for the first time how welds and fault welds are reopened during contractional deformation, having direct implications for the subsurface exploration of natural resources.
                                            
                                            
                                        Chiara Montemagni, Stefano Zanchetta, Martina Rocca, Igor M. Villa, Corrado Morelli, Volkmar Mair, and Andrea Zanchi
                                    Solid Earth, 14, 551–570, https://doi.org/10.5194/se-14-551-2023, https://doi.org/10.5194/se-14-551-2023, 2023
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                                                The Vinschgau Shear Zone (VSZ) is one of the largest and most significant shear zones developed within the Late Cretaceous thrust stack in the Austroalpine domain of the eastern Alps. 40Ar / 39Ar geochronology constrains the activity of the VSZ between 97 and 80 Ma. The decreasing vorticity towards the core of the shear zone, coupled with the younging of mylonites, points to a shear thinning behavior. The deepest units of the Eo-Alpine orogenic wedge were exhumed along the VSZ.
                                            
                                            
                                        Jordi Miró, Oriol Ferrer, Josep Anton Muñoz, and Gianreto Manastchal
                                    Solid Earth, 14, 425–445, https://doi.org/10.5194/se-14-425-2023, https://doi.org/10.5194/se-14-425-2023, 2023
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                                                Using the Asturian–Basque–Cantabrian system and analogue (sandbox) models, this work focuses on the linkage between basement-controlled and salt-decoupled domains and how deformation is accommodated between the two during extension and subsequent inversion. Analogue models show significant structural variability in the transitional domain, with oblique structures that can be strongly modified by syn-contractional sedimentation. Experimental results are consistent with the case study.
                                            
                                            
                                        Junichi Fukuda, Takamoto Okudaira, and Yukiko Ohtomo
                                    Solid Earth, 14, 409–424, https://doi.org/10.5194/se-14-409-2023, https://doi.org/10.5194/se-14-409-2023, 2023
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                                                We measured water distributions in deformed quartz by infrared spectroscopy mapping and used the results to discuss changes in water distribution resulting from textural development. Because of the grain size reduction process (dynamic recrystallization), water contents decrease from 40–1750 wt ppm in host grains of ~2 mm to 100–510 wt ppm in recrystallized regions composed of fine grains of ~10 µm. Our results indicate that water is released and homogenized by dynamic recrystallization.
                                            
                                            
                                        Bastien Walter, Yves Géraud, Alexiane Favier, Nadjib Chibati, and Marc Diraison
                                        EGUsphere, https://doi.org/10.5194/egusphere-2023-397, https://doi.org/10.5194/egusphere-2023-397, 2023
                                    Preprint archived 
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                                                Lake Abhe in southwestern Djibouti is known for its exposures of massive hydrothermal chimneys and hot springs on the lake’s eastern shore. This study highlights the control of the main structural faults of the area on the development of these hydrothermal features. This work contributes to better understand hydrothermal fluid pathways in this area and may help further exploration for the geothermal development of this remarkable site.
                                            
                                            
                                        Michael Rudolf, Matthias Rosenau, and Onno Oncken
                                    Solid Earth, 14, 311–331, https://doi.org/10.5194/se-14-311-2023, https://doi.org/10.5194/se-14-311-2023, 2023
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                                                Analogue models of tectonic processes rely on the reproduction of their geometry, kinematics and dynamics. An important property is fault behaviour, which is linked to the frictional characteristics of the fault gouge. This is represented by granular materials, such as quartz sand. In our study we investigate the time-dependent frictional properties of various analogue materials and highlight their impact on the suitability of these materials for analogue models focusing on fault reactivation.
                                            
                                            
                                        Jessica Barabasch, Joyce Schmatz, Jop Klaver, Alexander Schwedt, and Janos L. Urai
                                    Solid Earth, 14, 271–291, https://doi.org/10.5194/se-14-271-2023, https://doi.org/10.5194/se-14-271-2023, 2023
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                                                We analysed Zechstein salt with microscopes and observed specific microstructures that indicate much faster deformation in rock salt with fine halite grains when compared to salt with larger grains. This is important because people build large cavities in the subsurface salt for energy storage or want to deposit radioactive waste inside it. When engineers and scientists use grain-size data and equations that include this mechanism, it will help to make better predictions in geological models.
                                            
                                            
                                        Nicolás Molnar and Susanne Buiter
                                    Solid Earth, 14, 213–235, https://doi.org/10.5194/se-14-213-2023, https://doi.org/10.5194/se-14-213-2023, 2023
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                                                Progression of orogenic wedges over pre-existing extensional structures is common in nature, but deciphering the spatio-temporal evolution of deformation from the geological record remains challenging. Our laboratory experiments provide insights on how horizontal stresses are transferred across a heterogeneous crust, constrain which pre-shortening conditions can either favour or hinder the reactivatation of extensional structures, and explain what implications they have on critical taper theory.
                                            
                                            
                                        Tania Habel, Martine Simoes, Robin Lacassin, Daniel Carrizo, and German Aguilar
                                    Solid Earth, 14, 17–42, https://doi.org/10.5194/se-14-17-2023, https://doi.org/10.5194/se-14-17-2023, 2023
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                                                The Central Andes are one of the most emblematic reliefs on Earth, but their western flank remains understudied. Here we explore two rare key sites in the hostile conditions of the Atacama desert to build cross-sections, quantify crustal shortening, and discuss the timing of this deformation at ∼20–22°S. We propose that the structures of the Western Andes accommodated  significant crustal shortening here, but only during the earliest stages of mountain building.
                                            
                                            
                                        Naïm Célini, Frédéric Mouthereau, Abdeltif Lahfid, Claude Gout, and Jean-Paul Callot
                                    Solid Earth, 14, 1–16, https://doi.org/10.5194/se-14-1-2023, https://doi.org/10.5194/se-14-1-2023, 2023
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                                                We investigate the peak temperature of sedimentary rocks of the SW Alps (France), using Raman spectroscopy on carbonaceous material. This method provides an estimate of the peak temperature achieved by organic-rich rocks. To determine the timing and the tectonic context of the origin of these temperatures we use 1D thermal modelling. We find that the high temperatures up to 300 °C were achieved during precollisional extensional events, not during tectonic burial in the Western Alps.
                                            
                                            
                                        Luke N. J. Wedmore, Tess Turner, Juliet Biggs, Jack N. Williams, Henry M. Sichingabula, Christine Kabumbu, and Kawawa Banda
                                    Solid Earth, 13, 1731–1753, https://doi.org/10.5194/se-13-1731-2022, https://doi.org/10.5194/se-13-1731-2022, 2022
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                                                Mapping and compiling the attributes of faults capable of hosting earthquakes are important for the next generation of seismic hazard assessment. We document 18 active faults in the Luangwa Rift, Zambia, in an active fault database. These faults are between 9 and 207 km long offset Quaternary sediments, have scarps up to ~30 m high, and are capable of hosting earthquakes from Mw 5.8 to 8.1. We associate the Molaza Fault with surface ruptures from two unattributed M 6+ 20th century earthquakes.
                                            
                                            
                                        Michał P. Michalak, Lesław Teper, Florian Wellmann, Jerzy Żaba, Krzysztof Gaidzik, Marcin Kostur, Yuriy P. Maystrenko, and Paulina Leonowicz
                                    Solid Earth, 13, 1697–1720, https://doi.org/10.5194/se-13-1697-2022, https://doi.org/10.5194/se-13-1697-2022, 2022
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                                                When characterizing geological/geophysical surfaces, various geometric attributes are calculated, such as dip angle (1D) or dip direction (2D). However, the boundaries between specific values may be subjective and without optimization significance, resulting from using default color palletes. This study proposes minimizing cosine distance among within-cluster observations to detect 3D anomalies. Our results suggest that the method holds promise for identification of megacylinders or megacones.
                                            
                                            
                                        Sivaji Lahiri, Kitty L. Milliken, Peter Vrolijk, Guillaume Desbois, and Janos L. Urai
                                    Solid Earth, 13, 1513–1539, https://doi.org/10.5194/se-13-1513-2022, https://doi.org/10.5194/se-13-1513-2022, 2022
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                                                Understanding the mechanism of mechanical compaction is important. Previous studies on mechanical compaction were mostly done by performing experiments.  Studies on natural rocks are rare due to compositional heterogeneity of the sedimentary succession with depth. Due to remarkable similarity in composition and grain size, the Sumatra subduction complex provides a unique opportunity to study the micromechanism of mechanical compaction on natural samples.
                                            
                                            
                                        Dongwon Lee, Nikolaos Karadimitriou, Matthias Ruf, and Holger Steeb
                                    Solid Earth, 13, 1475–1494, https://doi.org/10.5194/se-13-1475-2022, https://doi.org/10.5194/se-13-1475-2022, 2022
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                                                This research article focuses on filtering and segmentation methods employed in high-resolution µXRCT studies for crystalline rocks, bearing fractures, or fracture networks, of very small aperture. Specifically, we focus on the identification of artificially induced (via quenching) fractures in Carrara marble samples. Results from the same dataset from all five different methods adopted were produced and compared with each other in terms of their output quality and time efficiency.
                                            
                                            
                                        Alberto Ceccato, Giulia Tartaglia, Marco Antonellini, and Giulio Viola
                                    Solid Earth, 13, 1431–1453, https://doi.org/10.5194/se-13-1431-2022, https://doi.org/10.5194/se-13-1431-2022, 2022
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                                                The Earth's surface is commonly characterized by the occurrence of fractures, which can be mapped, and their can be geometry quantified on digital representations of the surface at different scales of observation. Here we present a series of analytical and statistical tools, which can aid the quantification of fracture spatial distribution at different scales. In doing so, we can improve our understanding of how fracture geometry and geology affect fluid flow within the fractured Earth crust.
                                            
                                            
                                        Giulio Viola, Giovanni Musumeci, Francesco Mazzarini, Lorenzo Tavazzani, Manuel Curzi, Espen Torgersen, Roelant van der Lelij, and Luca Aldega
                                    Solid Earth, 13, 1327–1351, https://doi.org/10.5194/se-13-1327-2022, https://doi.org/10.5194/se-13-1327-2022, 2022
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                                                A structural-geochronological approach helps to unravel the Zuccale Fault's architecture. By mapping its internal structure and dating some of its fault rocks, we constrained a deformation history lasting 20 Myr starting at ca. 22 Ma. Such long activity is recorded by now tightly juxtaposed brittle structural facies, i.e. different types of fault rocks. Our results also have implications on the regional evolution of the northern Apennines, of which the Zuccale Fault is an important structure.
                                            
                                            
                                        Wan-Lin Hu
                                    Solid Earth, 13, 1281–1290, https://doi.org/10.5194/se-13-1281-2022, https://doi.org/10.5194/se-13-1281-2022, 2022
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                                                Having a seismic image is generally expected to enable us to better determine fault geometry and thus estimate geological slip rates accurately. However, the process of interpreting seismic images may introduce unintended uncertainties, which have not yet been widely discussed. Here, a case of a shear fault-bend fold in the frontal Himalaya is used to demonstrate how differences in interpretations can affect the following estimates of slip rates and dependent conclusions.
                                            
                                            
                                        Manuel D. Menzel, Janos L. Urai, Estibalitz Ukar, Thierry Decrausaz, and Marguerite Godard
                                    Solid Earth, 13, 1191–1218, https://doi.org/10.5194/se-13-1191-2022, https://doi.org/10.5194/se-13-1191-2022, 2022
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                                                Mantle rocks can bind large quantities of carbon by reaction with CO2, but this capacity requires fluid pathways not to be clogged by carbonate. We studied mantle rocks from Oman to understand the mechanisms allowing their transformation into carbonate and quartz. Using advanced imaging techniques, we show that abundant veins were essential fluid pathways driving the reaction. Our results show that tectonic stress was important for fracture opening and a key ingredient for carbon fixation.
                                            
                                            
                                        Jean-Baptiste P. Koehl, Steffen G. Bergh, and Arthur G. Sylvester
                                    Solid Earth, 13, 1169–1190, https://doi.org/10.5194/se-13-1169-2022, https://doi.org/10.5194/se-13-1169-2022, 2022
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                                                The San Andreas fault is a major active fault associated with ongoing earthquake sequences in southern California. The present study investigates the development of the Indio Hills area in the Coachella Valley along the main San Andreas fault and the Indio Hills fault. The Indio Hills area is located near an area with high ongoing earthquake activity (Brawley seismic zone), and, therefore, its recent tectonic evolution has implications for earthquake prediction.
                                            
                                            
                                        Jin Lai, Dong Li, Yong Ai, Hongkun Liu, Deyang Cai, Kangjun Chen, Yuqiang Xie, and Guiwen Wang
                                    Solid Earth, 13, 975–1002, https://doi.org/10.5194/se-13-975-2022, https://doi.org/10.5194/se-13-975-2022, 2022
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                                                (1) Structural diagenesis analysis is performed on the ultra-deep tight sandstone. (2) Fracture and intergranular pores are related to the low in situ stress magnitudes. (3) Dissolution is associated with the presence of fracture.
                                            
                                            
                                        Hamed Fazlikhani, Wolfgang Bauer, and Harald Stollhofen
                                    Solid Earth, 13, 393–416, https://doi.org/10.5194/se-13-393-2022, https://doi.org/10.5194/se-13-393-2022, 2022
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                                                Interpretation of newly acquired FRANKEN 2D seismic survey data in southeeastern Germany shows that upper Paleozoic low-grade metasedimentary rocks and possible nappe units are transported by Variscan shear zones to ca. 65 km west of the Franconian Fault System (FFS). We show that the locations of post-Variscan upper Carboniferous–Permian normal faults and associated graben and half-graben basins are controlled by the geometry of underlying Variscan shear zones.
                                            
                                            
                                        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.
                                            
                                            
                                        Berit Schwichtenberg, Florian Fusseis, Ian B. Butler, and Edward Andò
                                    Solid Earth, 13, 41–64, https://doi.org/10.5194/se-13-41-2022, https://doi.org/10.5194/se-13-41-2022, 2022
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                                                Hydraulic rock properties such as porosity and permeability are relevant factors that have an impact on groundwater resources, geological repositories and fossil fuel reservoirs.  We investigate the influence of chemical compaction upon the porosity evolution in salt–biotite mixtures and related transport length scales by conducting laboratory experiments in combination with 4-D analysis. Our observations invite a renewed discussion of the effect of sheet silicates on chemical compaction.
                                            
                                            
                                        David Healy and Stephen Paul Hicks
                                    Solid Earth, 13, 15–39, https://doi.org/10.5194/se-13-15-2022, https://doi.org/10.5194/se-13-15-2022, 2022
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                                                The energy transition requires operations in faulted rocks. To manage the technical challenges and public concern over possible induced earthquakes, we need to quantify the risks. We calculate the probability of fault slip based on uncertain inputs, stresses, fluid pressures, and the mechanical properties of rocks in fault zones. Our examples highlight the specific gaps in our knowledge. Citizen science projects could produce useful data and include the public in the discussions about hazards.
                                            
                                            
                                        Manuel I. de Paz-Álvarez, Thomas G. Blenkinsop, David M. Buchs, George E. Gibbons, and Lesley Cherns
                                    Solid Earth, 13, 1–14, https://doi.org/10.5194/se-13-1-2022, https://doi.org/10.5194/se-13-1-2022, 2022
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                                                We describe a virtual geological mapping course implemented in response to travelling and social restrictions derived from the ongoing COVID-19 pandemic. The course was designed to replicate a physical mapping exercise as closely as possible with the aid of real field data and photographs collected by the authors during previous years in the Cantabrian Zone (NW Spain). The course is delivered through Google Earth via a KMZ file with outcrop descriptions and links to GitHub-hosted photographs.
                                            
                                            
                                        Yueyang Xia, Jacob Geersen, Dirk Klaeschen, Bo Ma, Dietrich Lange, Michael Riedel, Michael Schnabel, and Heidrun Kopp
                                    Solid Earth, 12, 2467–2477, https://doi.org/10.5194/se-12-2467-2021, https://doi.org/10.5194/se-12-2467-2021, 2021
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                                                The 2 June 1994 Java tsunami earthquake ruptured in a seismically quiet subduction zone and generated a larger-than-expected tsunami. Here, we re-process a seismic line across the rupture area. We show that a subducting seamount is located up-dip of the mainshock in a region that did not rupture during the earthquake. Seamount subduction modulates the topography of the marine forearc and acts as a seismic barrier in the 1994 earthquake rupture.
                                            
                                            
                                        Steffen Abe and Hagen Deckert
                                    Solid Earth, 12, 2407–2424, https://doi.org/10.5194/se-12-2407-2021, https://doi.org/10.5194/se-12-2407-2021, 2021
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                                                We use numerical simulations and laboratory experiments on rock samples to investigate how stress conditions influence the geometry and roughness of fracture surfaces. The roughness of the surfaces was analyzed in terms of absolute roughness and scaling properties. The results show that the surfaces are self-affine but with different scaling properties between the numerical models and the real rock samples. Results suggest that stress conditions have little influence on the surface roughness.
                                            
                                            
                                        Chao Deng, Rixiang Zhu, Jianhui Han, Yu Shu, Yuxiang Wu, Kefeng Hou, and Wei Long
                                    Solid Earth, 12, 2327–2350, https://doi.org/10.5194/se-12-2327-2021, https://doi.org/10.5194/se-12-2327-2021, 2021
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                                                This study uses seismic reflection data to interpret the geometric relationship and evolution of intra-basement and rift-related structures in the Enping sag in the northern South China Sea. Our observations suggest the primary control of pre-existing thrust faults is the formation of low-angle normal faults, with possible help from low-friction materials, and the significant role of pre-existing basement thrust faults in fault geometry, paleotopography, and syn-rift stratigraphy of rift basins.
                                            
                                            
                                        Sonia Yeung, Marnie Forster, Emmanuel Skourtsos, and Gordon Lister
                                    Solid Earth, 12, 2255–2275, https://doi.org/10.5194/se-12-2255-2021, https://doi.org/10.5194/se-12-2255-2021, 2021
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                                                We do not know when the ancient Tethys Ocean lithosphere began to founder, but one clue can be found in subduction accreted tectonic slices, including Gondwanan basement terranes on the island of Ios, Cyclades, Greece. We propose a 250–300 km southwards jump of the subduction megathrust with a period of flat-slab subduction followed by slab break-off. The initiation and its subsequent rollback of a new subduction zone would explain the onset of Oligo–Miocene extension and accompanying magmatism.
                                            
                                            
                                        Rahul Prabhakaran, Giovanni Bertotti, Janos Urai, and David Smeulders
                                    Solid Earth, 12, 2159–2209, https://doi.org/10.5194/se-12-2159-2021, https://doi.org/10.5194/se-12-2159-2021, 2021
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                                                Rock fractures are organized as networks with spatially varying arrangements. Due to networks' influence on bulk rock behaviour, it is important to quantify network spatial variation. We utilize an approach where fracture networks are treated as spatial graphs. By combining graph similarity measures with clustering techniques, spatial clusters within large-scale fracture networks are identified and organized hierarchically. The method is validated on a dataset with nearly 300 000 fractures.
                                            
                                            
                                        Olivier Lacombe, Nicolas E. Beaudoin, Guilhem Hoareau, Aurélie Labeur, Christophe Pecheyran, and Jean-Paul Callot
                                    Solid Earth, 12, 2145–2157, https://doi.org/10.5194/se-12-2145-2021, https://doi.org/10.5194/se-12-2145-2021, 2021
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                                                This paper aims to illustrate how the timing and duration of contractional deformation associated with folding in orogenic forelands can be constrained by the dating of brittle mesostructures observed in folded strata. The study combines new and already published absolute ages of fractures to provide, for the first time, an educated discussion about the factors controlling the duration of the sequence of deformation encompassing layer-parallel shortening, fold growth, and late fold tightening.
                                            
                                            
                                        Vincent Famin, Hugues Raimbourg, Muriel Andreani, and Anne-Marie Boullier
                                    Solid Earth, 12, 2067–2085, https://doi.org/10.5194/se-12-2067-2021, https://doi.org/10.5194/se-12-2067-2021, 2021
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                                                Sediments accumulated in accretionary prisms are deformed by the compression imposed by plate subduction. Here we show that deformation of the sediments transforms some minerals in them. We suggest that these mineral transformations are due to the proliferation of microorganisms boosted by deformation. Deformation-enhanced microbial proliferation may change our view of sedimentary and tectonic processes in subduction zones.
                                            
                                            
                                        Marta Adamuszek, Dan M. Tămaş, Jessica Barabasch, and Janos L. Urai
                                    Solid Earth, 12, 2041–2065, https://doi.org/10.5194/se-12-2041-2021, https://doi.org/10.5194/se-12-2041-2021, 2021
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                                                We analyse folded multilayer sequences in the Ocnele Mari salt mine (Romania) to gain insight into the long-term rheological behaviour of rock salt. Our results indicate the large role of even a small number of impurities in the rock salt for its effective mechanical behaviour. We demonstrate how the development of folds that occur at various scales can be used to constrain the viscosity ratio in the deformed multilayer sequence.
                                            
                                            
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                Short summary
            Studying how earthquakes spread deep within the faults they originate from is crucial to improving our understanding of the earthquake process. We mapped preserved ancient earthquake surfaces that are now exposed in South Africa and studied their relationship with the shape and type of rocks surrounding them. We determined that these surfaces are not random and are instead associated with specific kinds of rocks and that their shape is linked to the evolution of the faults in which they occur.
            Studying how earthquakes spread deep within the faults they originate from is crucial to...