Articles | Volume 8, issue 6
https://doi.org/10.5194/se-8-1211-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/se-8-1211-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
21 Dec 2017
Research article |
| 21 Dec 2017
Constraints on the rheology of the lower crust in a strike-slip plate boundary: evidence from the San Quintín xenoliths, Baja California, Mexico
Thomas van der Werf
Department of Earth Sciences, Utrecht University, Utrecht, the Netherlands
Department of Earth Sciences, Utrecht University, Utrecht, the Netherlands
Department of Geoscience, University of Wisconsin-Madison, Madison, Wisconsin, USA
Leo Marcel Kriegsman
Department of Earth Sciences, Utrecht University, Utrecht, the Netherlands
Department of Research & Education, Naturalis Biodiversity Center, Leiden, the Netherlands
Andreas Kronenberg
Department of Geology and Geophysics, Texas A&M University, College Station, Texas, USA
Basil Tikoff
Department of Geoscience, University of Wisconsin-Madison, Madison, Wisconsin, USA
Martyn R. Drury
Department of Earth Sciences, Utrecht University, Utrecht, the Netherlands
Related authors
No articles found.
Valentin Basch, Martyn R. Drury, Oliver Plumper, Eric Hellebrand, Laura Crispini, Fabrice Barou, Marguerite Godard, and Elisabetta Rampone
Eur. J. Mineral., 33, 463–477, https://doi.org/10.5194/ejm-33-463-2021, https://doi.org/10.5194/ejm-33-463-2021, 2021
Short summary
Short summary
This paper investigates the possibility for melts to migrate within extensively deformed crystals and assesses the impact of this intracrystalline melt percolation on the chemical composition of the deformed crystal. We here document that the presence of melt within a crystal greatly enhances chemical diffusive re-equilibration between the percolating melt and the mineral and that such a process occurring at crystal scale can impact the large-scale composition of the oceanic lithosphere.
Cristina G. Wilson, Randolph T. Williams, Kathryn Bateman, Basil Tikoff, and Thomas F. Shipley
Solid Earth Discuss., https://doi.org/10.5194/se-2021-69, https://doi.org/10.5194/se-2021-69, 2021
Preprint withdrawn
Short summary
Short summary
In this contribution, we address the current gap in undergraduate geoscience education on uncertainty. We present a framework for teaching students to characterize, assess, and convey uncertainty that is suitable for both traditional in-person and virtual field experiences. The framework provides students relief from the distress of "not knowing" by providing a language to communicate uncertainty, and affirms their scientific growth by making reductions in uncertainty more conspicuous.
Ernst-Jan N. Kuiper, Ilka Weikusat, Johannes H. P. de Bresser, Daniela Jansen, Gill M. Pennock, and Martyn R. Drury
The Cryosphere, 14, 2429–2448, https://doi.org/10.5194/tc-14-2429-2020, https://doi.org/10.5194/tc-14-2429-2020, 2020
Short summary
Short summary
A composite flow law model applied to crystal size distributions from the NEEM deep ice core predicts that fine-grained layers in ice from the last Glacial period localize deformation as internal shear zones in the Greenland ice sheet deforming by grain-size-sensitive creep. This prediction is consistent with microstructures in Glacial age ice.
Ernst-Jan N. Kuiper, Johannes H. P. de Bresser, Martyn R. Drury, Jan Eichler, Gill M. Pennock, and Ilka Weikusat
The Cryosphere, 14, 2449–2467, https://doi.org/10.5194/tc-14-2449-2020, https://doi.org/10.5194/tc-14-2449-2020, 2020
Short summary
Short summary
Fast ice flow occurs in deeper parts of polar ice sheets, driven by high stress and high temperatures. Above 262 K ice flow is further enhanced, probably by the formation of thin melt layers between ice crystals. A model applying an experimentally derived composite flow law, using temperature and grain size values from the deepest 540 m of the NEEM ice core, predicts that flow in fine-grained layers is enhanced by a factor of 10 compared to coarse-grained layers in the Greenland ice sheet.
Andreas K. Kronenberg, Hasnor F. B. Hasnan, Caleb W. Holyoke III, Richard D. Law, Zhenxian Liu, and Jay B. Thomas
Solid Earth, 8, 1025–1045, https://doi.org/10.5194/se-8-1025-2017, https://doi.org/10.5194/se-8-1025-2017, 2017
Short summary
Short summary
Methods of measuring trace water contents of quartz at high resolution using synchrotron infrared radiation and spectroscopy are described and applied to deformed rocks of the Moine Thrust of NW Scotland and the Main Central Thrust of the Himalaya in NW India. By imaging OH absorption bands, variations in water content can be linked to deformation microstructures, providing information on the histories of deformation, recovery, introduction and loss of water, and water weakening.
Ilka Weikusat, Ernst-Jan N. Kuiper, Gill M. Pennock, Sepp Kipfstuhl, and Martyn R. Drury
Solid Earth, 8, 883–898, https://doi.org/10.5194/se-8-883-2017, https://doi.org/10.5194/se-8-883-2017, 2017
Short summary
Short summary
Understanding the flow of large ice masses on Earth is a major challenge in our changing climate. Deformation mechanisms are governed by the strong anisotropy of ice. As anisotropy is currently moving into the focus of ice sheet flow studies, we provide a detailed analysis of microstructure data from natural ice core samples which directly relate to anisotropic plasticity. Our findings reveal surprising dislocation activity which seems to contradict the concept of macroscopic ice anisotropy.
Related subject area
Structural geology
Multiscalar 3D temporal structural characterisation of Smøla island, mid-Norwegian passive margin: an analogue for unravelling the tectonic history of offshore basement highs
Extensional fault geometry and evolution within rifted margin hyper-extended continental crust leading to mantle exhumation and allochthon formation
Selection and Characterisation of the Target Fault for Fluid-Induced Activation and Earthquake Rupture Experiments
Impact of faults on the remote stress state
Naturally fractured reservoir characterization in heterogeneous sandstones: insight for Uranium In Situ Recovery (Imouraren, Niger)
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)
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
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)
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
Short summary
Short summary
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.
Júlia Gómez-Romeu and Nick Kusznir
Solid Earth, 15, 477–492, https://doi.org/10.5194/se-15-477-2024, https://doi.org/10.5194/se-15-477-2024, 2024
Short summary
Short summary
We investigate the extensional fault geometry and its evolution during the stretching and thinning of continental crust and lithosphere leading to continental breakup. We focus on the fault-controlled processes that thin and rupture the final 10 km of continental crust at magma-poor margins prior to mantle exhumation. We show that isostatic fault rotation in response to extension is fundamental to understanding the formation of tectonic structures observed on seismic reflection data.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-586, https://doi.org/10.5194/egusphere-2024-586, 2024
Short summary
Short summary
We detail the selection and characterization of a fault zone for earthquake experiments within the FEAR project at the Bedretto Lab. Overcoming challenges of data collection near faults, FEAR conducts experiments to study earthquakes. We selected the fault from the structural inventory at the Rotondo granite based on geometry, monitorability, and hydro-mechanical properties, employing remote sensing, borehole logging, and geological mapping to yield a 3D model.
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
Short summary
Short summary
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.
Maxime Jamet, Gregory Ballas, Roger Soliva, Olivier Gerbeaud, Thierry Lefebvre, Christine Leredde, and Didier Loggia
EGUsphere, https://doi.org/10.5194/egusphere-2024-435, https://doi.org/10.5194/egusphere-2024-435, 2024
Short summary
Short summary
Naturally fractured reservoirs are governed by multi-scale transfer properties from matrix to large-scale structures. In this paper, using a multi-method/-scale analysis, we characterize the structural network of a NFR. This characterization is obtained via analysis on satellite images, structure measurements, logs and hydrogeological tests. We found that clustered structures have a significant impact on permeability anisotropy compared to distributed sub-orthogonal joint sets.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
(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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Cited articles
Ashby, M. F. and Verrall, R. A.: Diffusion-accommodated flow and superplasticity, Acta Metall. Mater., 21, 149–163, 1973.
Atwater, T.: Plate tectonic history of the northeast Pacific and western North America, in: The eastern Pacific Ocean and Hawaii, edited by: Winterer, E. L., Hussong, D. M., and Dekker, R. W., Geological Society of America, Boulder, Colorado, N, 21–72, 1989.
Atwater, T. and Stock, J.: Pacific-North America plate tectonics of the Neogene southwestern United States: an update, Int. Geol. Rev., 40, 375–402, 1998.
Avé Lallemant, H. G.: Experimental deformation of diopside and websterite, Tectonophysics, 48, 1–27, 1978.
Barton, M. D., Battles, D. A., Debout, G. E., Capo, R. C., Christensen, J. N., Davis, S. R., and Trim, H. E.: Mesozoic contact metamorphism in the western United States, in: Metamorphism and crustal evolution of the western United States, edited by: Ernst, W. G., Pentice Hall, Los Angeles, California, Rubey, 7, 110–178, 1988.
Basu, A. R.: Hot spots, mantle plumes and a model for the origin of ultramafic xenoliths in alkali basalts, Earth Planet. Sc. Lett., 28, 261–274, 1975.
Basu, A. R.: Textures, microstructures and deformation of ultramafic xenoliths from San Quintin, Baja California, Tectonophysics, 43, 213–246, 1977.
Behr, W. M. and Hirth, G.: Rheological properties of the mantle lid beneath the Mojave region in southern California, Earth Planet. Sc. Lett., 393, 60–72, 2014.
Bestmann, M., Prior, D. J., and Grasemann, B.: Characterisation of deformation and flow mechanics around porphyroclasts in a calcite marble ultramylonite by means of EBSD analysis, Tectonophysics, 413, 185–200, 2006.
Blenkisop, T. G.: Deformation Microstructures and Mechanisms in Minerals and Rocks, Springer, 2000.
Bons, P. D. and Jessell, M. W.: Micro-shear zones in experimentally deformed octachloropropane, J. Struct. Geol., 21, 323–334, 1999.
Brace, W. and Kohlstedt, D.: Limits on lithospheric stress imposed by laboratory experiments, J. Geophys. Res., 85, 6248–6252, 1980.
Brey, G. and Köhler, T.: Geothermobarometry in four-phase lherzolites II. New thermobarometers, and practical assessment of existing thermobarometers, J. Petrol., 31, 1353–1378, 1990.
Bunge, H.: Texture Analysis in Materials Science: Mathematical Models, Butterworths, London, 593 pp., 1982.
Burov, E. and Watts, A.: The long-term strength of continental lithosphere: "jelly sandwich" or "crème brûlée"?, GSA today, 16, 4–10, 2006.
Cabanes, N. and Mercier, J.: Insight into the upper mantle beneath an active extensional zone: the spinel-peridotite xenoliths from San Quintin (Baja California, Mexico), Contrib. Mineral. Petr., 100, 374–382, 1988.
Cao, S. and Neubauer, F.: Deep crustal expressions of exhumed strike-slip fault systems: Shear zone initiation on rheological boundaries, Earth-Sci. Rev., 162, 155–176, 2016.
Carpenter, B., Saffer, D., and Marone, C.: Frictional properties and sliding stability of the San Andreas fault from deep drill core, Geology, 40, 759–762, 2012.
Carter, N. L. and Avé Lallemant, H. G.: High temperature flow of dunite and peridotite, Geol. Soc. Am. Bull., 81, 2181–2202, 1970.
Chatzaras, V., Tikoff, B., Newman, J., Withers, A. C., and Drury, M. R.: Mantle strength of the San Andreas fault system and the role of mantle-crust feedbacks, Geology, 43, 891–894, 2015.
Chatzaras, V., Kruckenberg, S. C., Cohen, S. M., Medaris, L. G., Withers, A. C., and Bagley, B.: Axial-type olivine crystallographic preferred orientations: The effect of strain geometry on mantle texture, J. Geophys. Res.-Sol. Ea., 121, 4895–4922, 2016.
Chen, W. P. and Molnar, P.: Focal depths of intracontinental and intraplate earthquakes and their implications for the thermal and mechanical properties of the lithosphere, J. Geophys. Res., 88, 4183–4214, 1983.
Connolly, J. and Petrini, K.: An automated strategy for calculation of phase diagram sections and retrieval of rock properties as a function of physical conditions, J. Metamorph. Geol., 20, 697–708, 2002.
De Bresser, J., Ter Heege, J., and Spiers, C.: Grain size reduction by dynamic recrystallization: can it result in major rheological weakening?, Int. J. Earth. Sci., 90, 28–45, 2001.
De Kloe, R., Drury, M. R., and Van Roermund, H. L. M.: Evidence for stable grain boundary melt films in experimentally deformed olivine-orthopyroxene rocks, Phys. Chem. Miner., 27(7), 480-494, 2000.
DeMets, C.: A reappraisal of seafloor spreading lineations in the Gulf of California: Implications for the transfer of Baja California to the Pacific Plate and estimates of Pacific-North America motion, Geophys. Res. Lett., 22, 3545–3548, 1995.
Depine, G. V., Andronicos, C. L., and Phipps-Morgan, J.: Near-isothermal conditions in the middle and lower crust induced by melt migration, Nature, 452, 80–83, 2008.
Dickinson, W. R.: Tectonic implications of Cenozoic volcanism in coastal California, Geol. Soc. Am. Bull., 109, 936–954, 1997.
Dimanov, A. and Dresen, G.: Rheology of synthetic anorthite-diopside aggregates: Implications for ductile shear zone, J. Geophys. Res., 110, B07203, https://doi.org/10.1029/2004JB003431, 2005.
Dixon, T. H., Miller, M., Farina, F., Wang, H., and Johnson, D.: Present-day motion of the Sierra Nevada block and some tectonic implications for the Basin and Range province, North American Cordillera, Tectonics, 19, 1–24, 2000.
Dixon, T. H., Norabuena, E., and Hotaling, L.: Paleoseismology and Global Positioning System: Earthquake-cycle effects and geodetic versus geologic fault slip rates in the Eastern California shear zone, Geology, 31, 55–58, 2003.
Downes, H.: The nature of the lower continental crust of Europe: petrological and geochemical evidence from xenoliths, Phys. Earth Planet. In., 79, 195–218, 1993.
Druiventak, A., Trepmann, C. A., Renner, J., and Hanke, K.: Low-temperature plasticity of olivine during high stress deformation of peridotite at lithospheric conditions – An experimental study, Earth Planet. Sc. Lett., 311, 199–211, 2011.
Drury, M. R. and Fitz Gerald, J. D.: Grain boundaries melt films in an experimentally deformed olivine-orthopyroxene rock: implications for melt distribution in upper mantle rocks, Geophys. Res. Lett., 23, 701–704, 1996.
Drury, M. R. and Humphreys, F. J.: Microstructural shear criteria associated with grain-boundary sliding during ductile deformation, J. Struct. Geol., 10, 83–89, 1988.
Drury, M. R. and Urai, J. L.: Deformation-related recrystallization processes, Tectonophysics, 172, 235–253, 1990.
Drury, M. R., Lallemant, H. A., Pennock, G. M., and Palasse, L. N.: Crystal preferred orientation in peridotite ultramylonites deformed by grain size sensitive creep, Étang de Lers, Pyrenees, France, J. Struct. Geol., 33, 1776–1789, 2011.
Fletcher, J. M. and Munguia, L.: Active continental rifting in southern Baja California, Mexico: Implications for plate motion partitioning and the transition to seafloor spreading in the Gulf of California, Tectonics, 19, 1107–1123, 2000.
Fletcher, J. M., Kohn, B. P., Foster, D. A., and Gleadow, A. J.: Heterogeneous Neogene cooling and exhumation of the Los Cabos block, southern Baja California: Evidence from fission-track thermochronology, Geology, 28, 107–110, 2000.
Fliervoet, T. F., Drury, M. R., and Chopra, P. N.: Crystallographic preferred orientations and misorientations in some olivine rocks deformed by diffusion or dislocation creep, Tectonophysics, 303, 1–27, 1999.
Freed, A. M. and Bürgmann, R.: Evidence of power-law flow in the Mojave desert mantle, Nature, 430, 548–551, 2004.
Gastil, R. G.: Plutonic zones in the Peninsular Ranges of southern California and northern Baja California, Geology, 3, 361–363, 1975.
Gastil, R. G. and Miller, R. H.: The Prebatholithic Stratigraphy of Peninsular California, GSA Special Papers, 279, 7–27, 1993.
Gastil, R. G., Phillips, R. P., and Allison, E. C.: Reconnaissance geology of the state of Baja California, GSA Memoirs, 140, 1–201, 1975.
Gómez Barreiro, J., Lonardelli, I., Wenk, H. R., Dresen, G., Rybacki, E., Ren, Y., and Tomeì, C. N.: Preferred orientation of anorthite deformed experimentally in Newtonian creep, Earth Planet. Sc. Lett., 264, 188–207, 2007.
Gottstein, G. and Shvindlerman, L. S.: Triple junction drag and grain growth in 2D polycrystals, Acta Mater., 50, 703–713, 2000.
Green, H. W. and Borch, R. S.: A new molten-salt cell for precision stress measurement at high-pressure, Eur. J. Mineral., 1, 213–219, 1989.
Griffin, W. and O'Reilly, S. Y.: Is the continental Moho the crust-mantle boundary?, Geology, 15, 241–244, 1987.
Handy, M. R., Mulch, A., Rosenau, M., and Rosenberg, C. L.: The role of fault zones and melts as agents of weakening, hardening and differentiation of the continental crust: a synthesis, Geological Society, London, Special Publications, 186, 305–332, 2001.
Hansen, L. N., Zimmerman, M. E., and Kohlstedt, D. L.: Grain boundary sliding in San Carlos olivine: Flow law parameters and crystallographic-preferred orientation, J. Geophys. Res., 116, B08201, https://doi.org/10.1029/2011JB008220, 2011.
Hansen, L. N., Cheadle, M. J., John, B. E., Swapp, S. M., Dick, H. J., Tucholke, B. E., and Tivey, M. A.: Mylonitic deformation at the Kane oceanic core complex: Implications for the rheological behavior of oceanic detachment faults, Geochem. Geophy. Geosy., 14, 3085–3108, 2013.
Helmstaedt, H., Anderson, O. L., and Gavasci, A. T.: Petrofabric studies of eclogite, spinel-Websterite, and spinel-lherzolite Xenoliths from kimberlite-bearing breccia pipes in southeastern Utah and northeastern Arizona, J. Geophys. Res., 77, 4350–4365, 1972.
Hidas, K., Falus, G., Szabó, C., Szabó, P. J., Kovács, I., and Földes, T.: Geodynamic implications of flattened tabular equigranular textured peridotites from the Bakony-Balaton Highland Volcanic Field (Western Hungary), J. Geodyn., 43, 484–503, 2007.
Hirth, G. and Kohlstedt, D. L.: Experimental constraints on the dynamics of the partially molten upper mantle: Deformation in the diffusion creep regime, J. Geophys. Res., 100, 1981–2001, 1995.
Hirth, G. and Kohlstedt, D.: Rheology of the upper mantle and the mantle wedge: A view from the experimentalists, in: Inside the subduction Factory, edited by: Eiler, J., American Geophysical Union, Washington, D.C., 83–105, 2003.
Holland, T. and Powell, R.: An internally consistent thermodynamic data set for phases of petrological interest, J. Metamorph. Geol., 16, 309–343, 1998.
Holtzman, B. K., Kohlstedt, D. L., Zimmerman, M. E., Heidelbach, F., Hiraga, T., and Hustoft, J.: Melt segregation and strain partitioning: implications for seismic anisotropy and mantle flow, Science, 301, 1227–1230, 2003.
Jackson, J.: Strength of the continental lithosphere: time to abandon the jelly sandwich?, GSA today, 12, 4–9, 2002.
Ji, S. and Mainprice, D.: Recrystallization and fabric development in plagioclase, J. Geol., 98, 65–79, 1990.
Ji, S., Mainprice D., and Boudier, F.: Sense of shear in high-temperature movement zones from the fabric asymmetry of plagioclase feldspars, J. Struct. Geol., 10, 73–81, 1988.
Ji, S., Wirth, R., Rybacki, E., and Jiang, Z.: High-temperature plastic deformation of quartz-plagioclase multilayers by layer-normal compression, J. Geophys. Res., 105, 16651–16664, 2000.
Ji, S., Shao, T., Salisbury, M. H., Sun, S., Michibayashi, K., Zhao, W., Long, C., Liang, F., and Satsukawa, T.: Plagioclase preferred orientation and induced seismic anisotropy in mafic igneous rocks, J. Geophys. Res.-Sol. Ea., 119, 8064–8088, https://doi.org/10.1002/2014JB011352, 2014.
Jiang, Z., Prior, D. J., and Wheeler, J.: Albite crystallographic preferred orientation and grain misorientation distribution in a low-grade mylonite: implications for granular flow, J. Struct. Geol., 22, 1663–1674, 2000.
Johnson, E. A. and Rossman, G. R.: The concentration and speciation of hydrogen in feldspars using FTIR and 1H MAS NMR spectroscopy, Am. Mineral., 88, 901–911, 2003.
Johnson, S. E., Tate, M. C., and Fanning, C. M.: New geological and SHRIMP U- Pb zircon data in the Peninsular Ranges batholith, Baja California, México: Evidence for a suture?, Geology, 27, 743–746, 1999.
Jung, H. and Karato, S.: Water-induced fabric transitions in olivine, Science, 293, 1460–1463, https://doi.org/10.1126/science.1062235, 2001.
Jung, H., Park, M., Jung, S., and Lee, J.: Lattice preferred orientation, water content, and seismic anisotropy of orthopyroxene, J. Earth Sci., 21, 555–568, 2010.
Kenkmann, T. and Dresen, G.: Dislocation microstructure and phase distribution in a lower crustal shear zone-an example from the Ivrea-Zone, Italy, Int. J. Earth Sci., 91, 445–458, 2002.
Kidder, S., Hirth, G., Avouac, J.-P., and Behr, W.: The influence of stress history on the grain size and microstructure of experimentally deformed quartzite, J. Struct. Geol., 83, 194–206, 2016.
Kohlstedt, D. L., Evans, B., and Mackwell, S. J.: Strength of the lithosphere: Constraints imposed by laboratory experiments, J. Geophys. Res., 100, 17587–17602, 1995.
Kruse, R. and Stünitz, H.: Deformation mechanisms and phase distribution in mafic high temperature mylonites from the Jotun Nappe, Southern Norway, Tectonophysics, 303, 223–249, 1999.
Kruse, R., Stünitz, H., and Kunze, K.: Dynamic recrystallization processes in plagioclase porphyroclasts, J. Struct. Geol., 23, 1781–1802, 2001.
Langenheim, V. E. and Jachens, R. C.: Crustal structure of the Peninsular Ranges batholith from magnetic data: Implications for Gulf of California rifting, Geophys. Res. Lett., 30, 1597, https://doi.org/10.1029/2003GL017159, 2003.
Legg, M. R., Wong, V. O., and Suarez-Vidal, F.: Geologic structure and tectonics of the inner continental borderland of northern Baja California, in: The Gulf and Peninsular Province of the Californias, edited by: Dauphin, J. and Simoneit, B., American Association of Petroleum Geologists Memoir, 47, 145–177, 1991.
Lewis, J. L., Day, S. M., Magistrale, H., Castro, R. R., Rebollar, C., Astiz, L., Eakins, J., Vernon, F. L., and Brune, J. N.: Crustal thickness of the peninsular ranges and gulf extensional province in the Californias, J. Geophys. Res., 106, 13599–13611, 2001.
Lockner, D. A., Morrow, C., Moore, D., and Hickman, S.: Low strength of deep San Andreas fault gouge from SAFOD core, Nature, 472, 82–85, 2011.
Long, M. D.: Frequency-dependent shear wave splitting and heterogeneous anisotropic structure beneath the Gulf of California region, Phys. Earth Planet. In., 182, 59–72, 2010.
Lopez-Sanchez, M. A. and Llana-Fúnez, S.: An evaluation of different measures of dynamically recrystallized grain size for paleopiezometry or paleowattometry studies, Solid Earth, 6, 475–495, https://doi.org/10.5194/se-6-475-2015, 2015.
Luhr, J. F. and Aranda-Gómez, J. J.: Mexican peridotite xenoliths and tectonic terranes: correlations among vent location, texture, temperature, pressure, and oxygen fugacity, J. Petrol., 38, 1075–1112, 1997.
Luhr, J. F., Aranda-Gómez, J. J., and Housh, T. B.: San Quintín volcanic field, Baja California Norte, México: geology, petrology, and geochemistry, J. Geophys. Res., 100, 10353–10380, 1995.
Mehl, L. and Hirth, G.: Plagioclase preferred orientation in layered mylonites: Evaluation of flow laws for the lower crust, J. Geophys. Res., 113, B05202, https://doi.org/10.1029/2007JB005075, 2008.
Miranda, E. A., Hirth, G., and John, B. E.: Microstructural evidence for the transition from dislocation creep to dislocation-accommodated grain boundary sliding in naturally deformed plagioclase, J. Struct. Geol., 92, 30–45, 2016.
Mosenfelder, J. L., Rossman, G. R., and Johnson E. A.: Hydrous species in feldspars: A reassessment based on FTIR and SIMS, Am. Mineral., 100, 1209–1221, 2015.
Negrete-Aranda, R., Contreras, J., and Spelz, R. M.: Viscous dissipation, slab melting, and post-subduction volcanism in south-central Baja California, Mexico, Geosphere, 9, 1714–1728, 2013.
Nicolas, A. and Poirier, J. P.: Crystalline Plasticity and Solid State Flow in Metamorphic Rocks, John Wiley & Sons, London; New York, 1976.
Olsen, T. S. and Kohlstedt, D. L.: Analysis of dislocations in some naturally deformed plagioclase feldspars, Phys. Chem. Miner., 11, 153–160, 1984.
Palasse, L., Vissers, R., Paulssen, H., Basu, A., and Drury, M.: Microstructural and seismic properties of the upper mantle underneath a rifted continental terrane (Baja California): An example of sub-crustal mechanical asthenosphere?, Earth Planet. Sc. Lett., 345, 60–71, 2012.
Paulssen, H. and de Vos, D.: Slab remnants beneath the Baja California peninsula: Seismic constraints and tectonic implications, Tectonophysics, https://doi.org/10.1016/j.tecto.2016.09.021, 719–720, 27–36, 2017.
Peslier, A. H. and Luhr, J. F.: Hydrogen loss from olivines in mantle xenoliths from Simcoe (USA) and Mexico: Mafic alkalic magma ascent rates and water budget of the sub-continental lithosphere, Earth Planet. Sci. Lett., 242, 302–319, 2006.
Piazolo, S., Bons, P. D., Jessell, M. W., Evans, L., and Passchier, C. W.: Dominance of Microstructural Processes and Their Effect on Microstructural Development: Insights from Numerical Modelling of Dynamic Recrystallization, Geological Society, London, Special Publications, 200, 149–170, 2002.
Plattner, C., Malservisi, R., Dixon, T. H., LaFemina, P., Sella, G., Fletcher, J., and Suarez-Vidal, F.: New constraints on relative motion between the Pacific plate and Baja California microplate (Mexico) from GPS measurements, Geophys. J. Int., 170, 1373–1380, 2007.
Plattner, C., Malservisi, R., and Govers, R.: On the plate boundary forces that drive and resist Baja California motion, Geology, 37, 359–362, 2009.
Pollitz, F. F., Wicks, C., and Thatcher, W.: Mantle flow beneath a continental strike-slip fault: postseismic deformation after the 1999 Hector Mine earthquake, Science, 293, 1814–1818, https://doi.org/10.1126/science.1061361, 2001.
Précigout, J. and Hirth, G.: B-type olivine fabric induced by grain boundary sliding, Earth Planet. Sc. Lett., 395, 231–240, 2014.
Ree, J. H.: Grain boundary sliding and development of grain boundary openings in experimentally deformed octachloropropane, J. Struct. Geol., 16, 403–418, 1994.
Reyners, M., Eberhart-Phillips, D., and Stuart, G.: The role of fluids in lower-crustal earthquakes near continental rifts, Nature, 446, 1075–1078, https://doi.org/10.1038/nature05743, 2007.
Rogers, G., Saunders A., Terrell D., Verma S., and Marriner G.: Geochemistry of Holocene volcanic rocks associated with ridge subduction in Baja California, Mexico, Nature, 315, 389–392, 1985.
Rosenberg, C. L. and Berger, A.: Syntectonic Melt Pathways in Granitic Gneisses, and Melt-Induced Transitions in Deformation Mechanisms, Phys. Chem. Earth Pt. A, 26, 287–293, 2001.
Rothstein, D. A. and Manning, C. E.: Geothermal gradients in continental magmatic arcs: Constraints from the eastern Peninsular Ranges batholith, Baja California, México, in: Tectonic evolution of northwestern México and the southwestern USA, edited by: Johnson, S. E., Paterson, S. R., Fletcher, J. M., Girty, G. H., Kimbrough, D. L., and Martín-Barajas, A., Geological Society of America, Special Paper 374, 337–354, 2003.
Rudnick, R. L.: Xenoliths – samples of the lower continental crust, Continental lower crust, 23, 269–316, 1992.
Rybacki, E. and Dresen, G.: Dislocation and diffusion creep of synthetic anorthite aggregates, J. Geophys. Res., 105, 26017–26036, 2000.
Rybacki, E. M., Gottschalk, R. W., and Dresen, G.: Influence of water fugacity and activation volume on flow properties of fine-grained anorthite aggregates, J. Geophys. Res., 111, B03203, https://doi.org/10.1029/2005JB003663, 2006.
Satsukawa, T., Ildefonse, B., Mainprice, D., Morales, L. F. G., Michibayashi, K., and Barou, F.: A database of plagioclase crystal preferred orientations (CPO) and microstructures – implications for CPO origin, strength, symmetry and seismic anisotropy in gabbroic rocks, Solid Earth, 4, 511–542, https://doi.org/10.5194/se-4-511-2013, 2013.
Schmidt, K., Wetmore, P., Alsleben, H., and Paterson, S.: Mesozoic tectonic evolution of the southern Peninsular Ranges batholith, Baja California, Mexico: Long-lived history of a collisional segment in the Mesozoic Cordilleran arc, Geol. Soc. Am. Mem., 211, 645–668, 2014.
Silver, L. and Chappell, B.: The Peninsular Ranges Batholith: An insight into the evolution of the Cordilleran batholiths of southwestern North America, Earth Env. Sci. T. R. So., 79, 105–121, 1988.
Skemer, P. and Karato, S. I.: Sheared lherzolite xenoliths revisited, J. Geophys. Res-Sol. Ea., 113, B07205, https://doi.org/10.1029/2007JB005286, 2008.
Skemer, P., Katayama, I., Jiang, Z., and Karato, S.: The misorientation index: Development of a new method for calculating the strength of lattice-preferred orientation, Tectonophysics, 411, 157–167, 2005.
Soustelle, V., Tommasi, A., Demouchy, S., and Ionov, D.: Deformation and fluid–rock interaction in the supra-subduction mantle: microstructures and water contents in peridotite xenoliths from the Avacha Volcano, Kamchatka, J. Petrol., 51, 363–394, 2010.
Spencer, J. E. and Normark, W. R.: Tosco-Abreojos fault zone: A Neogene transform plate boundary within the Pacific margin of southern Baja California, Mexico, Geology, 7, 554–557, 1979.
Stewart, E. D., Holyoke, C. D., and Kronenberg, A. K.: High pressure deformation experiments using solid confining media and Griggs piston-cylinder methods: Appraisal of stress and deformation in talc assemblies, Tectonophysics, 588, 171–178, 2013.
Stock, J. and Hodges, K.: Pre-Pliocene extension around the Gulf of California and the transfer of Baja California to the Pacific Plate, Tectonics, 8, 99–115, 1989.
Storey, M., Rogers, G., Saunders, A., and Terrell, D.: San Quintín volcanic field, Baja California, Mexico: "within-plate" magmatism following ridge subduction, Terra Nova, 1, 195–202, 1989.
Stünitz, H., Gerald, J. F., and Tullis, J.: Dislocation generation, slip systems, and dynamic recrystallization in experimentally deformed plagioclase single crystals, Tectonophysics, 372, 215–233, 2003.
Svahnberg, H. and Piazolo, S.: The initiation of strain localisation in plagioclase-rich rocks: Insights from detailed microstructural analyses, J. Struct. Geol., 32, 1404–1416, 2010.
Tate, M. C. and Johnson, S. E.: Subvolcanic and deep-crustal tonalite genesis beneath the Méxican Peninsular Ranges, J. Geol., 108, 721–728, 2000.
Taylor, W.: An experimental test of some geothermometer and geobarometer formulations for upper mantle peridotites with application to the thermobarometry of fertile lherzolite and garnet websterite, Neues Jb. Miner.-Abh., 172, 381–408, 1998.
Teyssier, C. and Tikoff, B.: Strike-slip partitioned transpression of the San Andreas fault system: a lithospheric-scale approach, Geological Society, London, Special Publications, 135, 143–158, 1998.
Thatcher, W. and Pollitz, F. F.: Temporal evolution of continental lithospheric strength in actively deforming regions, GSA Today, 18, 4–11, 2008.
Thorkelson, D. J. and Breitsprecher, K.: Partial melting of slab window margins: genesis of adakitic and non-adakitic magmas, Lithos, 79, 25–41, 2005.
Titus, S. J., Medaris, L. G., Wang, H. F., and Tikoff, B.: Continuation of the San Andreas fault system into the upper mantle: evidence from spinel peridotite xenoliths in the Coyote Lake basalt, central California, Tectonophysics, 429, 1–20, 2007.
Todd, V. R., Erskine, B. G., and Morton, D. M.: Metamorphic and tectonic evolution of the Peninsular Ranges batholith, Englewood Cliffs, New Jersey, Prentice-Hall, 894–937, 1998.
Todd, V. R., Shaw, S. E., and Hammarstrom, J. M.: Cretaceous plutons of the Peninsular Ranges batholith, San Diego and westernmost Imperial counties, California: Intrusion across a Late Jurassic continental margin, Geological Society of America, Special paper, 374, 185–236, 2003.
Tommasi, A., Tikoff, B., and Vauchez, A.: Upper mantle tectonics: three-dimensional deformation, olivine crystallographic fabrics and seismic properties, Earth Planet. Sc. Lett., 168, 173–186, 1999.
Tommasi, A., Godard, M., Coromina, G., Dautria, J. M., and Barsczus, H.: Seismic anisotropy and compositionally induced velocity anomalies in the lithosphere above mantle plumes: a petrological and microstructural study of mantle xenoliths from French Polynesia, Earth Planet. Sc. Lett., 227, 539–556, 2004.
Toriumi, M.: Relation between dislocation density and subgrain size of naturally deformed olivine in peridotites, Contrib. Mineral. Petr., 68, 181–186, 1979.
Trepmann, C. A. and Stöckhert, B.: Quartz microstructures developed during non-steady state plastic flow at rapidly decaying stress and strain rate, J. Struct. Geol., 25, 2035–2051, 2003.
Twiss, R. J.: Theory and applicability of a recrystallized grain size paleopiezometer, in: Stress in the Earth Anonymous, Springer, 115, 227–244, 1977.
Ulrich, S. and Mainprice, D.: Does cation ordering in omphacite influence development of lattice-preferred orientation?, J. Struct. Geol., 27, 419–431, 2005.
Umhoefer, P. J.: Why did the Southern Gulf of California rupture so rapidly? – Oblique divergence across hot, weak lithosphere along a tectonically active margin, GSA Today, 21, 4–10, 2011.
Umhoefer, P. J. and Dorsey, R. J.: Translation of terranes: lessons from central Baja California, Mexico, Geology, 25, 1007–1010, 1997.
Underwood, E.: Quantitative Stereology, Addison-Wesley, Reading, Mass, 1970.
Valcke, S. L., Pennock, G. M., Drury, M. R., and De Bresser, J. H.: Electron backscattered diffraction as a tool to quantify subgrains in deformed calcite, Journal of Microscopy, 224, 264–276, 2006.
Van der Wal, D., Chopra, P., Drury, M., and Gerald, J. F.: Relationships between dynamically recrystallized grain size and deformation conditions in experimentally deformed olivine rocks, Geophys. Res. Lett., 20, 1479–1482, 1993.
Vauchez, A., Dineur, F., and Rudnick, R.: Microstructure, texture and seismic anisotropy of the lithospheric mantle above a mantle plume: insights from the Labait volcano xenoliths (Tanzania), Earth Planet. Sc. Lett., 232, 295–314, 2005.
Warren, J. M. and Hirth, G.: Grain size sensitive deformation mechanisms in naturally deformed peridotites, Earth Planet. Sc. Lett., 248, 438–450, 2006.
White, S. H., Burrows, S. E., Carreras, J., Shaw, N. D., and Humphreys, F. J.: On mylonites in ductile shear zones, J. Struct. Geol., 2, 175–187, 1980.
Wilks, K. R. and Carter, N. L.: Rheology of some continental lower crustal rocks, Tectonophysics, 182, 57–77, 1990.
Xie, Y., Wenk, H., and Matthies, S.: Plagioclase preferred orientation by TOF neutron diffraction and SEM-EBSD, Tectonophysics, 370, 269–286, 2003.
Yamasaki, T., Wright, T. J., and Houseman, G. A.: Weak ductile shear zone beneath a major strike-slip fault: Inferences from earthquake cycle model constrained by geodetic observations of the western North Anatolian Fault Zone, J. Geophys. Res.-Sol. Ea., 119, 3678–3699, 2014.
Zhang, X. and Paulssen, H.: Geodynamics of the Gulf of California from surface wave tomography, Phys. Earth Planet. In., 192–193, 59–67, 2012.
Zhang, X., Paulssen, H., Lebedev, S., and Meier, T.: 3D shear velocity structure beneath the Gulf of California from Rayleigh wave dispersion, Earth Planet. Sc. Lett., 279, 255–262, 2009.
Short summary
The strength of Earth's lower crust affects the cycle of earthquakes in tectonic plate boundaries. To understand the mechanical properties of the lower crust beneath northern Baja California, Mexico, we studied rocks, which were transferred to the surface during the eruption of Quaternary volcanoes. The lower crust is strongly deformed, hot, and dry. During transient events of deformation, the lower crust is weak, and its strength is similar to the strength of the upper mantle.
The strength of Earth's lower crust affects the cycle of earthquakes in tectonic plate...
