Articles | Volume 12, issue 4
https://doi.org/10.5194/se-12-971-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/se-12-971-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
26 Apr 2021
Research article |
| 26 Apr 2021
| 26 Apr 2021
Kinematics of subduction in the Ibero-Armorican arc constrained by 3D microstructural analysis of garnet and pseudomorphed lawsonite porphyroblasts from Île de Groix (Variscan belt)
Departamento de Geodinámica, Universidad de Granada, Granada, Spain
Instituto Andaluz de Ciencias de la Tierra, CSIC/Universidad de
Granada, Granada, Spain
Alejandro Ruiz-Fuentes
Departamento de Geodinámica, Universidad de Granada, Granada, Spain
Mohammad Sayab
Geological Survey of Finland, Espoo, Finland
Aidan Forde
Saorgus Energy Ltd, Kerry, Ireland
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
Analogue modelling of basin inversion: implications for the Araripe Basin (Brazil)
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
Impact of faults on the remote stress state
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
Subduction plate interface shear stress associated with rapid subduction at deep slow earthquake depths: example from the Sanbagawa belt, Southwest Japan
Multiple phase rifting and subsequent inversion in the West Netherlands Basin: implications for geothermal reservoir characterization
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
Shear zone evolution and the path of earthquake rupture
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
Geodynamic and seismotectonic model of a long-lived transverse structure: The Schio-Vicenza Fault System (NE Italy)
Neogene kinematics of the Giudicarie Belt and eastern Southern Alpine orogenic front (northern Italy)
Fault interpretation uncertainties using seismic data, and the effects on fault seal analysis: a case study from the Horda Platform, with implications for CO2 storage
Reply to Norini and Groppelli's comment on “Estimating the depth and evolution of intrusions at resurgent calderas: Los Humeros (Mexico)” by Urbani et al. (2020)
Emplacement of “exotic” Zechstein slivers along the inverted Sontra Graben (northern Hessen, Germany): clues from balanced cross sections and geometrical forward modeling
Frictional properties and microstructural evolution of dry and wet calcite–dolomite gouges
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.
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.
Karsten Reiter, Oliver Heidbach, and Moritz Ziegler
EGUsphere, https://doi.org/10.5194/egusphere-2023-1829, https://doi.org/10.5194/egusphere-2023-1829, 2023
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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.
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.
Yukinojo Koyama, Simon Richard Wallis, and Takayoshi Nagaya
EGUsphere, https://doi.org/10.5194/egusphere-2023-1442, https://doi.org/10.5194/egusphere-2023-1442, 2023
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Stress along the 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 path of exhumed rocks. The obtained results show differential stresses of 31.1–82.8 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
EGUsphere, https://doi.org/10.5194/egusphere-2023-1126, https://doi.org/10.5194/egusphere-2023-1126, 2023
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On the road to a sustainable planet, geothermal energy is considered as 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 inversion have influenced the distribution of the reservoir rocks, thus influencing the locations where geothermal energy can be applied.
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
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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.
Erik M. Young, Christie D. Rowe, and James D. Kirkpatrick
Solid Earth, 13, 1607–1629, https://doi.org/10.5194/se-13-1607-2022, https://doi.org/10.5194/se-13-1607-2022, 2022
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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.
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.
Dario Zampieri, Paola Vannoli, and Pierfrancesco Burrato
Solid Earth, 12, 1967–1986, https://doi.org/10.5194/se-12-1967-2021, https://doi.org/10.5194/se-12-1967-2021, 2021
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The long-lived Schio-Vicenza Fault System is a major shear zone cross-cutting the foreland and the thrust belt of the eastern southern Alps. We review 150 years of scientific works and explain its activity and kinematics, characterized by sinistral and dextral transcurrent motion along its southern and northern sections, respectively, by a geodynamic model that has the Adria indenter as the main actor and coherently reconciles the available geological and geophysical evidence collected so far.
Vincent F. Verwater, Eline Le Breton, Mark R. Handy, Vincenzo Picotti, Azam Jozi Najafabadi, and Christian Haberland
Solid Earth, 12, 1309–1334, https://doi.org/10.5194/se-12-1309-2021, https://doi.org/10.5194/se-12-1309-2021, 2021
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Balancing along geological cross sections reveals that the Giudicarie Belt comprises two kinematic domains. The SW domain accommodated at least ~ 18 km Late Oligocene to Early Miocene shortening. Since the Middle Miocene, the SW domain experienced at least ~ 12–22 km shortening, whereas the NE domain underwent at least ~ 25–35 km. Together, these domains contributed to ~ 40–47 km of sinistral offset of the Periadriatic Fault along the Northern Giudicarie Fault since the Late Oligocene.
Emma A. H. Michie, Mark J. Mulrooney, and Alvar Braathen
Solid Earth, 12, 1259–1286, https://doi.org/10.5194/se-12-1259-2021, https://doi.org/10.5194/se-12-1259-2021, 2021
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Generating an accurate model of the subsurface is crucial when assessing a site for CO2 storage, particularly for a fault-bound storage site that may act as a seal or could reactivate upon CO2 injection. However, we have shown how picking strategy, i.e. line spacing, chosen to create the model significantly influences any subsequent fault analyses but is surprisingly rarely discussed. This analysis has been performed on the Vette Fault bounding the Smeaheia potential CO2 storage site.
Stefano Urbani, Guido Giordano, Federico Lucci, Federico Rossetti, and Gerardo Carrasco-Núñez
Solid Earth, 12, 1111–1124, https://doi.org/10.5194/se-12-1111-2021, https://doi.org/10.5194/se-12-1111-2021, 2021
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Structural studies in active calderas have a key role in the exploration of geothermal systems. We reply in detail to the points raised by the comment of Norini and Groppelli (2020), strengthening the relevance of our structural fieldwork for geothermal exploration and exploitation in active caldera geothermal systems including the Los Humeros caldera.
Jakob Bolz and Jonas Kley
Solid Earth, 12, 1005–1024, https://doi.org/10.5194/se-12-1005-2021, https://doi.org/10.5194/se-12-1005-2021, 2021
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To assess the role smaller graben structures near the southern edge of the Central European Basin System play in the basin’s overall deformational history, we take advantage of a feature found on some of these structures, where slivers from older rock units appear along the graben's main fault, surrounded on both sides by younger strata. The implications for the geometry of the fault provide a substantially improved estimate for the magnitude of normal and thrust motion along the fault system.
Matteo Demurtas, Steven A.F. Smith, Elena Spagnuolo, and Giulio Di Toro
Solid Earth, 12, 595–612, https://doi.org/10.5194/se-12-595-2021, https://doi.org/10.5194/se-12-595-2021, 2021
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We performed shear experiments on calcite–dolomite gouge mixtures to better understand the behaviour of carbonates during sub-seismic to seismic deformation in the shallow crust. The development of a foliation in the gouge was only restricted to coseismic sliding, whereas fluidisation occurred over a wide range of slip velocities (sub-seismic to coseismic) in the presence of water. These observations will contribute to a better interpretation of the rock record.
Cited articles
Abu Sharib, A. S. A. A. and Bell, T. H.: Radical changes in bulk shortening
directions during orogenesis: Significance for progressive development of
regional folds and thrusts, Precambrian Res., 188, 1–20, 2011.
Abu Sharib, A. S. A. A. and Sanislav, I. V.: Polymetamorphism accompanied
switching in horizontal shortening during Isan Orogeny: example from the
Eastern Fold Belt, Mount Isa Inlier, Australia, Tectonophysics, 587,
146–167, 2013.
Aerden, D. G. A. M.: Kinematics of orogenic collapse in the Variscan Pyrenees
deduced from microstructures in porphyroblastic rocks from the
Lys-Caillaouas massif, Tectonophysics, 238, 139–160,
https://doi.org/10.1016/0040-1951(94)90053-1, 1994.
Aerden, D. G. A. M.: Porphyroblast non-rotation during crustal extension in the
Variscan Pyrenees, J. Struct. Geol., 17, 709–726, 1995.
Aerden, D. G. A. M.: Tectonic evolution of the Montagne Noire and a possible
orogenic model for syn-collisional exhumation of deep rocks, Hercynian belt,
France, Tectonics, 17, 62–79, 1998.
Aerden, D. G. A. M.: Correlating deformations in the Iberian Massif (Variscan
belt) using porphyroblasts; implications for the development of the
Ibero-Armorican Arc, J. Struct. Geol., 26, 177–196, 2004.
Aerden, D. G. A. M., Bell, T. H., Puga, E., Sayab, M., Lozano, J. A., and
Díaz de Federico, A.: Multi-stage mountain building vs. Relative plate
motions in the Betic Cordillera deduced from integrated microstructural and
petrological analysis of porphyroblast inclusion trails, Tectonophysics, 587,
188–206, 2013.
Aerden, D. G. A. M. and Malavieille, J.: Origin of a large-scale fold nappe in
the Montagne Noire, Variscan belt, France, J. Struct. Geol., 21,
1321–1333, 1999.
Aerden, D. G. A. M. and Sayab, M.: Probing the prodigious strain fringes from
Lourdes, J. Struct. Geol., 105, 88–106,
https://doi.org/10.1016/j.jsg.2017.11.001, 2017.
Aerden, D. G. A. M. and Ruiz-Fuentes, A.: X-ray computed microtomography of
spiral garnets: A new test of how they form, J. Struct. Geol.,
136, 104054, https://doi.org/10.1016/j.jsg.2020.104054, 2020.
Agostinelli, C. and Lund, U.: R package “circular”: Circular Statistics (version 0.4-93), available at: https://r-forge.r-project.org/projects/circular/, 2017.
Ali, A.: The tectono-metamorphic evolution of the Balcooma Metamorphic
Group, north-eastern Australia: a multidisciplinary approach, J.
Metamorph. Geol., 28, 397–422,
https://doi.org/10.1111/j.1525-1314.2010.00871.x, 2010.
Arenas, R., Rubio Pascual, F., Díaz García, F., and Martínez
Catalán, J. R.: High-pressure micro-inclusions and development of an
inverted metamorphic gradient in the Santiago Schists (Ordenes Complex, NW
Iberian Massif, Spain): evidence of subduction and syncollisional
decompression, J. Metamorph. Geol., 13, 141–164, 1995.
Arenas, R., Sanchez Martinez, S., Diez Fernandez, R., Gerdes, A., Abati, J.,
Fernandez-Suarez, J., Andonaegui, P., Cuadra, P. G., Carmona, A. L., Albert,
R., Fuenlabrada, J. M., and Rubio Pascual, F. J.: Allochthonous terrains
involved in the Variscan suture of NW Iberia: A review of their origin and
tectonothermal evolution, Earth-Sci. Rev., 161, 140–178, 2016.
Audren, C. and Triboulet, C.: Les chemins pression-température
enregistrés au cours de la formation de plis non-cylindriques dans les
schistes bleus de l'Ile de Groix (Bretagne méridionale, France), Comptes
Rendus de l'Académie des Sciences de Paris (II), 317, 259–265, 1993.
Audren, C., Triboulet, C., Chauris, L., Lefort, J. P., Vigneresse, J. L.,
Audrain, J., Thiéblemont, D., Goyallon, J., Jégouzo, P., Guennoc,
P., Augris, C., and Carn, A.: Notice explicative de la feuille Ile de Groix
à 1/25 000 (carte géologique), BRGM, Orléans, 1993.
Azor, A., Rubatto, D., Simancas, J. F., González Lodeiro, F.,
Martínez Poyatos, D., MartínParra, L. M., and Matas, J.: Rheic
Ocean ophiolitic remnants in southern Iberia questioned by SHRIMP U–Pb
zircon ages on the Beja-Acebuches amphibolites, Tectonics, 27, TC5006, 2008.
Ballevre, M., Pitra, P., and Bohn, M.: Lawsonite growth in the epidote blueschists
from the Ile de Groix (Armorican Massif, France): a potential geobarometer,
J. Metamorph. Geol., 21, 723–735, 2003.
Ballèvre, M., Bosse V., Ducassou, C., and Pitra, P.: Palaeozoic history
of the Armorican Massif: Models for the tectonic evolution of the suture
zones, C. R. Geosci., 341, 174–201, 2009.
Ballevre, M., Bosse, V., Dabard, M. P., Ducassou, C., Fourcade, S., Paquette, J. L., Peucat, J. J., and Pitra, P.:
Histoire Géologique du massif Armoricain: Actualitée de la
recherche. Bulletin de la Sociétée Géologique et
Minéralogique de Bretagne, Société géologique et
minéralogique de Bretagne, 10–11, 5–96, 2015.
Barnett-Moore, N., Müller, D. R., Williams, S., Skogseid, J., and Seton, M.: A reconstruction of the North Atlantic since the earliest Jurassic, Basin Research 30 (Suppl. 1), 160–185, https://doi.org/10.1111/bre.12214, 2018.
Béchennec, F., Hallégouët, B., Thiéblemont, D., and Thinon, I.:
Notice explicative, Carte géol. France (1/50 000), feuille Lorient
(383), BRGM, Orléans, 206 pp., 2012.
Bell, T. H.: Deformation partitioning and porphyroblast rotation in
metamorphic rocks: A radical reinterpretation, J. Metamorph.
Geol., 3, 109–118, 1985.
Bell, T. H. and Bruce, M. D.: The internal inclusion trail geometries preserved
within a first phase of porphyroblast growth, J. Struct. Geol.,
28, 236–252, 2006.
Bell, T. H. and Johnson, S. E.: Porphyroblast inclusion trails: the key to
orogenesis, J. Metamorph. Geol., 7, 279–310, 1989.
Bell, T. H. and Sapkota, J.: Episodic gravitational collapse and migration of
the mountain chain during orogenic roll-on in the Himalayas, J.
Metamorph. Geol., 30, 651–666, 2012.
Bell, T. H. and Welch, P. W.: Prolonged Acadian Orogenesis: revelations from
foliation intersection axis (FIA) controlled monazite dating of foliations
in porphyroblasts and matrix, Am. J. Sci., 302, 549–581,
2002.
Bell, T. H., Rubenach, M. J., and Flemming, P. D.: Porphyroblast nucleation,
growth and dissolution in regional metamorphic rocks as a function of
deformation partitioning during foliation development, J.
Metamorph. Geol., 4, 37–67, 1986.
Bell, T. H., Johnson, S. E., Davis, B., Forde, A., Hayward, N., and Wilkins,
C.: Porphyroblast inclusion-trail orientation data: eppure non son girate!
J. Metamorph. Geol., 10, 295–307, 1992.
Bell, T. H., Forde, A., and Wang, J.: A new indicator of movement direction
during orogenesis – measurement technique and application to the Alps, Terra
Nova, 7, 500–508, 1995.
Bell, T. H., Hickey, K. A., and Upton, G. J. G.: Distinguishing and correlating
multiple phases of metamorphism accross a multiply deformed region using the
axes of spiral, staircase, and sigmoidally curved inclusion trails in
garnet, J. Metamorph. Geol., 16, 767–794, 1998.
Bosse, V., Ballèvre, M., and Vidal, O.: Ductile thrusting recorded by the
garnet isograd from blueschist-facies metapelites of the Île de Groix,
Armorican Massif, France, J. Petrol., 43, 485–510, 2002.
Bosse, V., Féraud, G., Ballèvrec, M., Peucatc, J. J., and Corsini,
M.: Rb–Sr and 40Ar
Boudier, F. and Nicolas, A.: Interprétation nouvelle des relations entre
tectonique et métamorphisme dans l'île de Groix (Bretagne), B.
Soc. Géol. France, S7-XVIII, 135–144, 1976.
Bucher, H.: Role of gravity in orogenesis, Bull. Geol. Soc. Am., 67,
1295–1318, 1956.
Cannat, M.: Quartz microstructures and fabrics in the island of Groix
(Brittany, France), J. Struct. Geol., 7, 555–562, 1985.
Cobbold, P. R. and Quinquis, H.: Development of sheath folds in shear
regimes, J. Struct. Geol., 2, 119–126, 1980.
Cogné J., Daniel, J., and Ruhland, M.: L'Ile de Groix. Etude structurale
d'une série métamorphique à glaucophane en Bretagne
méridionale, in: Bulletin du Service de la carte géologique d'Alsace
et de Lorraine, 19-1, 41–96, https://doi.org/10.3406/sgeol.1966.1298, 1966.
Díaz García, F., Arenas, R., Martínez Catalán, J. R.,
González del Tánago, J., and Dunning, G. R.: Tectonic evolution of
the Careón ophiolite (northwest Spain): A remnant of the oceanic
lithosphere in the Variscan Belt, J. Geol., 107, 587–605,
1999.
Doube, M., Kłosowski, M. M., Arganda-Carreras, I., Cordeliéres, F.,
Dougherty, R. P., Jackson, J., Schmid, B., Hutchinson, J. R., and Shefelbine,
S. J.: BoneJ: free and extensible bone image analysis in ImageJ, Bone,
47, 1076–1079, https://doi.org/10.1016/j.bone.2010.08.023, 2010.
Engels, J. P.: The catazonal polymetamorphic rocks of Cabo Ortegal (NW Spain),
a structural and petrofabric study, Leidse Geologische Mededelingen, 48,
83–133, 1972.
Faure, M., Bé Mézème, E., Cocherie, A., Rossi, P., Chemenda, A.,
and Boutelier, D.: Devonian geodynamic evolution of the Variscan Belt,
insights from the French Massif Central and Massif Armoricain, Tectonics,
27, TC2005, https://doi.org/10.1029/2007TC002115, 2008.
Fay, C., Bell, T. H., and Hobbs, B. E.: Porphyroblast rotation versus
nonrotation: Conflict resolution!, Geology, 36, 307–310, 2008.
Felix, C. and Fransolet, A. M.: Pseudomorphes à épidote s.l.,
paragonite, muscovite s.l., chlorite, albite; de porphyroblastes de
lawsonite (?) dans les glaucophanites de l'Île de groix (bretagne –
France), Annales de la Société Geologique de Belgique, 95, 323–334,
1972.
Hayward, N.: Determination of early fold axis orientations in multiply
deformed rocks using porphyroblast inclusion trails, Tectonophysics, 179,
353–369, 1990.
Hayward, N.: Microstructural analysis of the classical spiral garnet
porphyroblasts of south-east Vermont: evidence for non-rotation, J.
Metamorph. Geol., 10, 567–587, 1992.
Huddlestone-Holmes, C. R. and Ketcham, R. A.: An X-ray computed tomography
study of inclusion trail orientations in multiple porphyroblasts from a
single sample, Tectonophysics, 480, 305–320, 2010.
Jammes, S., Manatschal, G., Lavier, L., and Masini, E.: Tectonosedimentary evolution related to extreme crustal thinning ahead of a propagating ocean: example of the western Pyrenees, Tectonics, 28, TC4012, https://doi.org/10.1029/2008TC002406, 2009.
Kim, H. S. and Ree, J. H.: Permo-Triassic changes in bulk crustal shortening
direction during deformation and metamorphism of the Taebaeksan Basin, South
Korea using foliation intersection/inflection axes: Implications for
tectonic movement at the eastern margin of Eurasia during the Songrim
(Indosinian) orogeny, Tectonophysics, 587, 133–145,
https://doi.org/10.1016/j.tecto.2012.08.033, 2013.
Lagarde, J. L.: La déformation des roches dans les domaines
àschistosité subhorizontale. Applications à la nappe du
Canigou-Roc de France (Pyrénées orientales) et au complexe
crystallophyllien de Champtoceaux (Massif armoricain), PhD
thesis, Université de Rennes, 170 pp., 1980.
Li, B. and Massonne, H. J.: Contrasting metamorphic evolution of metapelites
from the Malpica-Tuy unit and the underlying so-called parautochthon at the
coast of NW Spain, Lithos, 286–287, 92–108,
https://doi.org/10.1016/j.lithos.2017.06.003, 2017.
Lucks, H., Schulz, B., Audren, C., and Triboulet, C.: Variscan pressure-temperature evolution of garnet pyroxenites and amphibolites in the Baie d’Audierne metamorphic series, Brittany (France), edited by: Martínez Catalán, J. R., Hatcher, R. D., Arenas, R., and Díaz García, F., Variscan-Appalachian dynamics: The building of the late Paleozoic basement: Boulder, Colorado, Geological Society of America Special Paper 364, 89–103, 2002.
Mardia, K. V. and Jupp, P. E.: Directional Statistics, John Wiley & Sons., 456 pp., 2009.
Mares, V. M.: Structural development of the Soldiers Cap Group in the Eastern
Fold Belt of the Mt Isa Inlier: a successive of horizontal and vertical
deformation events and large-scale shearing, Austral. J. Earth Sci., 45,
373–387, 1998.
Martínez Catalán, J. R.: Are the oroclines of the Variscan belt
related to late Variscan strike-slip tectonics?, Terra Nova, 23, 241–247,
https://doi.org/10.1111/j.1365-3121.2011.01005.x, 2011.
Martínez Catalaín, J. R., Arenas, R., Díaz García, F.,
Rubio Pascual, F. J., Abati, J., and Marquínez, J.: Variscan exhumation
of a subducted Palaeozoic continental margin: the basal units of the Ordenes
Complex, Galicia, NW Spain, Tectonics, 15, 106–121, 1996.
Martínez Catalán, J. R., Arenas, R., Díaz García, F., and
Abati, J.: Variscan accretionary complex of northwest Iberia: Terrane
correlation and succession of tectonothermal events, Geology, 25,
1103–1106, 1997.
Matte, P.: The Variscan collage and orogeny (480–290 Ma) and the tectonic
definition of the Armorica microplate: a review, Terra Nova, 13, 122–128,
2001.
Merle, O.: The building of the central Swiss Alps: An experimental approach,
Tectonophysics, 165, 41–56, 1989.
Munro, M. A. and Blenkinsop, T. G.: MARD – A moving average rose diagram
application for the geosciences, Comput. Geosci., 49, 112–120,
https://doi.org/10.1016/j.cageo.2012.07.012, 2012.
Nirrengarten, M., Manatschal, G., Tugend, J., Kusznir, N.J., and Sauter, D.: Kinematic Evolution of the Southern North Atlantic: Implications for the Formation of Hyperextended Rift Systems, Tectonics 37, 89–118, https://doi.org/10.1002/2017TC004495, 2018.
Philippon, M., Brun, J. P., and Gueydan, F.: Kinematic records of subduction
and exhumation in the Île de Groix blueschists (Hercynian belt; Western
France), J. Struct. Geol., 31, 1308–1321, 2009.
Quinquis, H.: Schistes bleus et déformation progressive: l'exemple de
l'Île de Groix (Massif Armoricain), Université de Rennes, 1, 1980.
Quinquis, H. and Choukroune, P.: The Ile de Groix blueschists in the
Hercynian chain – kinematical implications, B. Soc.
Geol. Fr., 2, 409–418, 1981.
Quinquis, H., Audren, C., Brun, J. P., and Cobbold, P. R.: Intense shear in
Ile de Groix blueschists and compatibility with subduction or obduction,
Nature, Lond., 273, 43–45, 1978.
Rosenfeld, J. L.: Rotated garnets in metamorphic rocks, Geological Society of
America, Special Paper 129, 102 pp., 1970.
Sayab, M.: Microstructural evidence for N–S shortening in the Mount Isa
Inlier (NW Queensland, Australia): the preservation of early W–E-trending
foliations in porphyroblasts revealed by independent 3D measurement
techniques, J. Struct. Geol., 27, 1445–1468, 2005.
Sayab, M., Aerden, D., Kuva, J., and Hassan, W. U.: Tectonic evolution of the
Karakoram metamorphic complex (NW Himalayas) reflected in the 3D structures
of spiral garnets: Insights from X-ray computed micro-tomography, Geosci.
Front., 3, 101113, https://doi.org/10.1016/j.gsf.2020.11.010, 2021.
Shah, S. Z., Sayab, M., Aerden, D. G. A. M., and Asif-Kahn, M.: Foliation intersection
axes preserved in garnet porphyroblasts from the Swat area, NW Himalaya: A
record of successive crustal shortening directions between the Indian plate
and Kohistan-Ladakh Island Arc, Tectonophysics, 509, 14–32, 2011.
Shelley, D. and Bossieère, G.: Ile de groix: retrogression and
structural developments in an extensional régime, J. Struct.
Geol., 21, 1441–1455, 1999.
Schindelin, J., Arganda-Carreras, I., Frise, E., Kaynig, V., Longair, M.,
Pietzsch, T., Preibisch, S., Rueden, C., Saalfeld, S., Schmid, B., Tinevez,
J. Y., White, D. J., Hartenstein, V., Eliceiri, K., Tomancak, P., and Cardona,
A.: Fiji: an open-source platform for biological-image analysis, Nat.
Methods, 9, 676–682, 2012.
Schulz, B., Audren, C., and Triboulet, C.: Regional vs contact metamorphism
of garnet metapelites in the vicinity of Late Variscan granites (Central
Armorican Domain, Brittany, France), Geol. Rundsch., 87, 78–93, 1998.
Schulz, B., Triboulet, C., Audren, C., Pfeifer, H. R., and Gilg, A.:
Two-stage prograde and retrograde Variscan metamorphism of
glaucophane-eclogites, blueschists and greenschists from Ile de Groix
(Brittany, France), Int. J. Earth Sci., 90, 871–889,
2001.
Spry, A.: The origin and sigdicance of snowball structure in garnet, J. Petrol., 4, 211–222, 1963.
Stallard, A. and Hickey, K.: Shear zone vs folding origin for spiral
inclusion trails in the Canton Schist, J. Struct. Geol., 23,
1845–1864, 2001.
Stallard, A. R., Hickey, K. A., and Upton, G. J.: Measurement and correlation
of microstructures: the case of foliation intersection axes, J.
Metamorph. Geol., 21, 241–252, 2003.
Triboulet, C.: Les glaucophanites et roches associeés de
l'île de Groix (Morbihan, France): étude minéralogique et
pétrogénétique, Contrib. Mineral. Petr., 45,
65–90, 1974.
Triboulet, C.: Subglaucophanic greenschists from Le-Pouldu, a transitional
area between blueschists and amphibolites from a paleozoic single
metamorphic belt in south Brittany, France, Comptes Rendus de l'Academie des
Sciences serie II, 315, 697–703, 1992.
Van Zuuren, A.: Structural petrology of an area near Santiago de Compostella
(NW Spain), Leidse Geologische Mededelingen, 45, 1–71, 1969.
Zhang, Q. and Fossen, H.: The dilemma of asymmetric porphyroclast systems
and sense of shear, J. Struct. Geol., 130, 103893,
https://doi.org/10.1016/j.jsg.2019.103893, 2020.
Zwart, H.: On the determination of polymorphic mineral associations and its
application to the Bosost area (central Pyrenees), Geologisches Rundschau,
52, 38–65, 1962.
Short summary
We studied the geometry of foliations and microfolds preserved within metamorphic garnet crystals using X-ray tomography. The studied rocks are blueschists from Ile de Groix formed during Late Devonian subduction of Gondwana under Armorica. Several sets of differently oriented microfabrics were found recording variations in the direction of subduction. Comparison with similar data for Iberia supports that Iberia rotated only 10–20° during the Cretaceous opening of the North Atlantic.
We studied the geometry of foliations and microfolds preserved within metamorphic garnet...
