Article
Multidisciplinary Sciences
Yixin Liu, Chuanhua Xu, Jiang Xu, Xuemin Zeng
Summary: The injection of fluids into fault gouges can disturb stress conditions and increase the risk of earthquakes. This study investigates the effect of water injection and shear deformation on the hydro-mechanical characteristics of fault gouges. The results show that injecting water significantly reduces the maximum shear strength, and the effect varies with the gouge fill material. Shear deformation increases the inhomogeneity of thickness distribution and leads to non-uniform distribution of injected water along the fault.
SCIENTIFIC REPORTS
(2022)
Article
Geochemistry & Geophysics
S. Nielsen, E. Spagnuolo, M. Violay, G. Di Toro
Summary: This study explores rock friction under crustal earthquake conditions and finds that faults undergo abrupt dynamic weakening. Different models are tested to explain the process, and it is found that a model considering both heat sources and sinks better fits the experimental results. The study also compares three numerical approximations for computing temperature in this type of problem.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Environmental Sciences
Evangelos Moulas, Boris Kaus, Bjorn Jamtveit
Summary: The metamorphism of dry, lower crust in orogens is often localized in shear zones composed of mechanically weaker rocks. Previous studies have suggested that shear zone development is preceded by brittle faults, which provide the necessary pathways for fluid migration and metamorphism. However, there is currently no unified model that links long-term geological deformation to fluid migration and metamorphic reactions. This study presents a visco-elasto-plastic model that explains the observed features of transformed lower crust through basic mechanical principles. This includes dynamic and heterogeneous pressure distribution in the reacting and deforming rock volumes, which can significantly impact fluid migration patterns and explain discrepancies in tectonic settings and inferred burial depths.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)
Article
Geochemistry & Geophysics
Jessica McBeck, Yehuda Ben-Zion, Francois Renard
Summary: In this study, the localization processes of volumetric and deviatoric strains in twelve triaxial compression experiments were quantified using X-ray tomography. It was found that rocks typically experience strain localization towards failure, with the maximum degree of localization occurring at 90% of the failure stress. Volumetric strain tends to localize more than deviatoric strain.
Article
Multidisciplinary Sciences
V Rubino, N. Lapusta, A. J. Rosakis
Summary: Lab experiments show that dynamic ruptures propagate through fault regions with fine rock gouge through complex and intermittent slip processes. These processes include repeated arrest of rupture propagation caused by friction strengthening at lower slip rates, and dynamic earthquake re-nucleation enabled by pronounced rapid friction weakening at higher slip rates.
Article
Geochemistry & Geophysics
Melodie E. French, Wenlu Zhu, Xiaohui Xiao, Brian Evans, David J. Prior
Summary: This study reports the strength and deformation behavior of Solnhofen limestone during its transition from brittle to ductile. The results show that the combined effects of water and temperature have complex influences on the deformation and strength of the limestone. At elevated temperatures, water-saturated limestone exhibits weakening in both the brittle and ductile fields. Moreover, the concurrent effects of pore water and temperature significantly reduce the pressure of the brittle to ductile transition. These findings are important for understanding the behavior of limestone in geological processes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Multidisciplinary Sciences
Wei Feng, Lu Yao, Chiara Cornelio, Rodrigo Gomila, Shengli Ma, Chaoqun Yang, Luigi Germinario, Claudio Mazzoli, Giulio Di Toro
Summary: Earthquakes often occur along faults where there is hot and pressurized water. Experimental studies show that the physical state of water (liquid, vapor, or supercritical) has an impact on the frictional resistance of faults. In this study, friction in gabbro faults with water in different states (vapor, liquid, and supercritical) was examined, and it was found that the friction behavior differs depending on the state of the water. The findings suggest that the formation of weak minerals, chemical bonding properties of water, and hydrodynamic lubrication could explain the weakening behavior of faults.
NATURE COMMUNICATIONS
(2023)
Article
Geochemistry & Geophysics
Jianye Chen, Luuk B. Hunfeld, Andre R. Niemeijer, Christopher J. Spiers
Summary: High-velocity friction experiments on simulated fault gouges sheared at high normal stress and to low displacement were performed, revealing the relationship between constitutive parameters and normal stress, providing important constraints for numerical modeling of induced rupture propagation. The experiments also found that different rock types in the Groningen field exhibit varying levels of resistance to rupture and proposed a micrometer-scale fault weakening mechanism.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
C. Cornelio, E. Spagnuolo, S. Aretusini, S. Nielsen, F. Passelegue, M. Violay, M. Cocco, G. Di Toro
Summary: During seismic slip, natural faults experience a sudden decrease in shear stress.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Randolph T. Williams, Christie D. Rowe, Kristina Okamoto, Heather M. Savage, Erin Eves
Summary: This study documents the mechanical and geochemical processes of fault rock development in the shallow San Andreas fault (Mojave segment), highlighting the diverse suite of fault rocks and significant changes in frictional strength caused by the interdependence of these processes. Spatial variations in fault-rock mineralogy and geochemistry indicate marked variations in their relative contribution to fault-rock evolution, suggesting a substantial departure from simple structures envisioned for near-surface seismogenic faults in numerical models is required.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2021)
Article
Physics, Applied
Matthew Nelms, Jonathan Lind, Jonathan Margraf, Sayyad Basim Qamar, Joshua Herrington, Andrew Robinson, Mukul Kumar, Nathan Barton
Summary: The science and engineering communities have a strong interest in experimental platforms to assess and enhance dynamic material deformation models. Although well-developed platforms already exist, there are still gaps to fill for strain and strain rate conditions encountered during impact and other high-rate loading scenarios. A recently developed platform addresses one such gap by utilizing in situ x-ray imaging to measure the transient closure of a cylindrical hole, allowing access to high strain rate and large strain conditions. In this study, further refinements were made to minimize the potential effects of porosity and anelasticity on the measurements, thereby isolating the strength effects for experimentation. The updated experimental setup employs a two-layer flyer design and elongated target to reduce tensile excursions associated with rarefaction wave interactions and enables direct assessment of commonly used strength models for dynamic metal simulations. The technique was applied to well-characterized tantalum material, establishing a robust connection to other experimental techniques. Additionally, simulations were conducted to explore potential deformation localization behavior using a sub-zone treatment of shear banding. Overall, an improved experimental configuration was developed and utilized to isolate strength effects in a wider range of materials.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Binxin Fu, Rosa M. Espinosa-Marzal
Summary: Nanoscale friction measurements were conducted on calcite single crystals to study the influence of surface roughness, contact aging, and different environments. The results showed that friction behavior varied significantly between dry and aqueous environments, with water environment even eliminating velocity-weakening friction caused by atomic attrition. Friction rate parameters and memory distance also exhibited differences between dry and aqueous environments, with implications for understanding fault stability and friction laws.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Geochemistry & Geophysics
E. Papachristos, I. Stefanou, J. Sulem
Summary: This study uses discrete elements simulations to investigate the frictional response of fault gouges, considering their previous ultra-cataclastic flow and long-time consolidation loading. The impact of particle characteristics (such as size, polydispersity) and shearing velocities on the gouge's response under seismogenic zone conditions is explored. Monte-Carlo analyses show that local stick-slip events disappear when a large number of numerical samples are averaged. The apparent material frictional response is largely unaffected by the spatial randomness of particles' position and particle size distribution, but is controlled by the mean particle size and the formation of shear bands.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geosciences, Multidisciplinary
J. B. Ruh, L. Tokle, W. M. Behr
Summary: Variation in the effective strength of the lithosphere is permitted by different deformation mechanisms operating in the crust and upper mantle. A reduction in olivine grain size can cause weakening of the lithosphere, facilitating continental rifting.
Editorial Material
Geochemistry & Geophysics
Ze'ev Reches, Jay Fineberg
Summary: Earthquakes are caused by dynamic fractures due to overstresses, not governed by the frictional properties of faults. Frictional interfaces can sustain a wide range of stresses before sliding, generating stress-fields and rupture dynamics. The values of stresses and energy dissipation are determined by fault frictional properties.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
E. Hosseinzadehsabeti, E. C. Ferre, T. B. Andersen, J. W. Geissman, D. Bilardello, G. Di Toro
Summary: This study focuses on pseudotachylytes formed in oceanic peridotites as a result of intraslab seismic rupture, utilizing AMS to reconstruct co-seismic deformation parameters. The findings reveal diverse seismic deformation recorded in these veins with unique insights into the dynamics of frictional melts at high spatial resolution.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Multidisciplinary Sciences
Matthew S. Tarling, Steven A. F. Smith, Marianne Negrini, Li-Wei Kuo, Wei-Hsin Wu, Alan F. Cooper
Summary: Based on microstructural analysis of nephrite jade samples from Taiwan, California, and New Zealand, a conceptual model for the evolution of nephrite jade is proposed. Four types of nephrite jade are distinguished based on formation mode and textural characteristics. The study suggests that different types of nephrite jade can evolve through processes such as dissolution-precipitation, crenulated and foliated metamorphic fabrics, and transient brittle deformation.
SCIENTIFIC REPORTS
(2022)
Article
Geochemistry & Geophysics
Li-Wei Kuo, Chien-Cheng Hung, Haibing Li, Stefano Aretusini, Jianye Chen, Giulio Di Toro, Elena Spagnuolo, Fabio Di Felice, Huan Wang, Jialiang Si, Hwo-Shuenn Sheu
Summary: The 2008 Wenchuan earthquake caused surface ruptures along the Longmenshan fault belt, with the Yingxiu-Beichuan fault and the Guanxian-Anxian faults being the most affected. Frictional experiments were conducted on the gouge materials from the Guanxian-Anxian faults, revealing that wet gouges have lower friction coefficients compared to those under room humidity conditions. Additionally, the gouges exhibited enhanced velocity-strengthening behavior at intermediate velocities, indicating a potential barrier to slip acceleration during fault propagation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
C. Cornelio, E. Spagnuolo, S. Aretusini, S. Nielsen, F. Passelegue, M. Violay, M. Cocco, G. Di Toro
Summary: During seismic slip, natural faults experience a sudden decrease in shear stress.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Review
Astronomy & Astrophysics
Massimo Cocco, Stefano Aretusini, Chiara Cornelio, Stefan B. Nielsen, Elena Spagnuolo, Elisa Tinti, Giulio Di Toro
Summary: Large seismogenic faults have fault cores surrounded by damage zones. Earthquakes are caused by rupture propagation and slip within fault cores, dissipating elastic strain energy. Understanding energy partitioning is crucial for explaining fault dynamic weakening and rupture processes. Fracture energy from various studies is reviewed, showing that fracture energy scales with fault slip. Material-dependent fracture energies are important at the microscale but negligible at the macroscale on natural faults.
ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Simone Masoch, Michele Fondriest, Rodrigo Gomila, Erik Jensen, Thomas M. Mitchell, Jose Cembrano, Giorgio Pennacchioni, Giulio Di Toro
Summary: This study investigates the structural variability of the Bolfin Fault Zone in Northern Chile and its impact on earthquake mechanics. The findings suggest that the fault zone contains multiple altered fault core strands and fluid-rich protobreccias, indicating extensive fluid percolation during fault activity.
JOURNAL OF STRUCTURAL GEOLOGY
(2022)
Article
Geochemistry & Geophysics
E. M. Conrad, N. Tisato, B. M. Carpenter, G. Di Toro
Summary: This study investigates the effects of frictional melt formation on the coseismic and interseismic strength of faults using a new energy-controlled rotary shear machine. The experiments reveal that the presence of melts modulates different stages of earthquakes and faulting. Monitoring acoustic emissions and vibrational waves during slip events can provide valuable insights into the underlying physical processes and help improve our understanding of earthquakes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Francesco Lazari, Angela Castagna, Stefan Nielsen, Ashley Griffith, Giorgio Pennacchioni, Rodrigo Gomila, Phil Resor, Chiara Cornelio, Giulio Di Toro
Summary: The frictional power per unit area Q played a crucial role in controlling earthquake rupture nucleation, propagation, and arrest. However, determining Q using geophysical methods is challenging. In this study, we estimated Q dissipated on a fault patch exhumed from 7-9 km depth by combining theoretical models, experimental data, and geological constraints. Our findings suggest that the grain-scale roughness of the boundary between frictional melt and host rock decreases with increasing Q. The estimated Q values range from 4-60 MW m-2, which are at the lower end of previous estimates.(c) 2023 Elsevier B.V. All rights reserved.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geology
H. Wang, H. B. Li, G. Di Toro, L. -w. Kuo, E. Spagnuolo, S. Aretusini, J. L. Si, S. -r. Song
Summary: Frictional melting occurred at shallow depths during the 2008 Wenchuan earthquake in China, instead of thermal pressurization. Rock friction experiments showed that fluid-rich fault gouges can generate pseudotachylytes under conditions expected for seismic slip. This suggests that seismic slip can be accommodated by multiple faults during large earthquakes.
Article
Multidisciplinary Sciences
Lu Yao, Shengli Ma, Giulio Di Toro
Summary: This paper presents experimental evidence of thermal pressurization (TP) weakening of seismic faults and suggests that TP processes could be significantly promoted by wear-induced sealing during earthquakes, even for relatively permeable faults.
NATURE COMMUNICATIONS
(2023)
Article
Geochemistry & Geophysics
S. Marty, A. Schubnel, H. S. Bhat, J. Aubry, E. Fukuyama, S. Latour, S. Nielsen, R. Madariaga
Summary: In this study, the precursory acoustic emission (AE) activity during the nucleation of stick-slip instability is used to investigate foreshock occurrence prior to natural earthquakes. The results of three stick-slip experiments on Indian metagabbro samples show that AE activity increases towards failure and is driven by fault slip velocity. The AE foreshock sequences follow an inverse Omori type law, and the magnitude of AEs increases towards failure.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Marshall C. Palmer, James M. Scott, Steven A. F. Smith, Petrus J. le Roux, Chris Harris, Marianne Negrini, Matthew S. Tarling
Summary: By analyzing the Sr isotope data from metasomatic rocks in the Dun Mountain Ophiolite, we have determined the timing of mantle and crust juxtaposition, providing evidence for the closure of a fore-arc ocean basin during the middle Jurassic.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Multidisciplinary Sciences
Wei Feng, Lu Yao, Chiara Cornelio, Rodrigo Gomila, Shengli Ma, Chaoqun Yang, Luigi Germinario, Claudio Mazzoli, Giulio Di Toro
Summary: Earthquakes often occur along faults where there is hot and pressurized water. Experimental studies show that the physical state of water (liquid, vapor, or supercritical) has an impact on the frictional resistance of faults. In this study, friction in gabbro faults with water in different states (vapor, liquid, and supercritical) was examined, and it was found that the friction behavior differs depending on the state of the water. The findings suggest that the formation of weak minerals, chemical bonding properties of water, and hydrodynamic lubrication could explain the weakening behavior of faults.
NATURE COMMUNICATIONS
(2023)
Article
Mineralogy
Matthew S. Tarling, Matteo Demurtas, Steven A. F. Smith, Jeremy S. Rooney, Marianne Negrini, Cecilia Viti, Jasmine R. Petriglieri, Keith C. Gordon
Summary: The study found that the serpentine mineral lizardite has strong Raman anisotropy in the OH-stretching region, and the wavenumber shifts depend on the orientation of the excitation laser relative to the crystallographic axes. By studying well-characterised lizardite samples, the relationship between crystallographic orientation and Raman wavenumber was quantified, providing a simple and cost-effective technique for measuring and quantifying lizardite-bearing serpentinite fault rocks. This technique is particularly useful when EBSD alone is insufficient.
EUROPEAN JOURNAL OF MINERALOGY
(2022)
Article
Geochemistry & Geophysics
Lingyu Zhang, Kristoffer Szilas
Summary: This study presents new petrological and geochemical data for the Narssaq Ultramafic Body (NUB) in the Itsaq Gneiss Complex of SW Greenland. The results indicate that the ultramafic rocks of NUB are not mantle residues, but instead represent crustal cumulates derived from high-Mg magmas.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Rong Xu, Sarah Lambart, Oliver Nebel, Ming Li, Zhongjie Bai, Junbo Zhang, Ganglan Zhang, Jianfeng Gao, Hong Zhong, Yongsheng Liu
Summary: This study investigated the iron isotope compositions of Cenozoic basalts in Southeast China, finding significant variations related to different types of basalts and their respective sources.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
C. J. Ebinger, Miriam C. Reiss, Ian Bastow, Mary M. Karanja
Summary: The East African rift system is formed above mantle upwellings and the formation of rifts is related to lithospheric thinning and magmatic activity. The amount of splitting varies spatially and the fast axes are predominantly parallel to the orientation of the rifts. Thick lithospheric modules have less splitting and different orientations, which may indicate mantle plume flow. Splitting rotates and increases in strength as it enters the rift zones, suggesting that the anisotropy is mainly present at shallow depths.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Correction
Geochemistry & Geophysics
Ekaterina Rojas-Kolomiets, Owen Jensen, Michael Bizimis, Gene Yogodzinski, Lukas Ackerman
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Robert W. Nicklas, Igor S. Puchtel, Ethan F. Baxter
Summary: Oxygen fugacity is a fundamental parameter for understanding redox processes in igneous systems. This study compares the Fe-XANES oxybarometry method with the V-in-olivine method for evaluating fO(2) in MORB lavas. The results show that the V-in-olivine method is not applicable to samples with low MgO content, and that the majority of Archean komatiite sources have lower fO(2) than modern MORB.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Chunfei Chen, Stephen F. Foley, Sebastian Tappe, Huange Ren, Lanping Feng, Yongsheng Liu
Summary: The volatile components CO2 and H2O play a major role in mantle melting and heterogeneity. In this study, Ca isotopes were used to trace the lithological heterogeneity in alkaline magmatic rocks. The results revealed the presence of K-richterite and carbonate components as the source of alkaline magmas with low delta 44/40Ca values. These findings highlight the importance of Ca isotopes as a robust tracer of lithological variation caused by volatiles in the Earth's upper mantle.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Timothee Jautzy, Gilles Rixhon, Regis Braucher, Romain Delunel, Pierre G. Valla, Laurent Schmitt, Aster Team
Summary: Although the current approach to estimate catchment-wide denudation rates using only 10Be concentrations has made significant progress in geomorphology, this study argues for the inclusion of 26Al measurements and testing of steady-state assumptions in slow eroding, formerly glaciated landscapes. The study conducted measurements of both 10Be and 26Al in stream sediments from the Vosges Massif in France and found that elevation, slope, channel steepness, and precipitation were the primary factors controlling denudation rates. The study also revealed a significant relationship between the extent of past glaciation and the cosmogenic (un-)steadiness in the stream sediments.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Erik van der Wiel, Douwe J. J. van Hinsbergen, Cedric Thieulot, Wim Spakman
Summary: Numerical models of Earth's mantle dynamics can predict the vigour and mixing of mantle flow, and the average slab sinking rates are an unexplored parameter that can provide intrinsic information on these characteristics. Through numerical experiments, it has been found that slab sinking rates are strongly correlated with mantle convection and mixing, and may explain geochemical observations from hotspot volcanoes.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)