Article
Physics, Fluids & Plasmas
Anna Pomyalov, Yuri Lubomirsky, Lara Braverman, Efim A. Brener, Eran Bouchbinder
Summary: A numerical study is conducted on self-healing slip pulses, which are solitonic structures propagating in frictional systems. The solutions show diverging length and strongly inertial propagation velocities when the driving stress approaches the frictional strength at a local minimum. An approximate scaling theory explains these observations quantitatively. The derived pulse solutions exhibit significant spatially-extended dissipation and an unconventional edge singularity.
Article
Materials Science, Multidisciplinary
H. Shlomai, D. S. Kammer, M. Adda-Bedia, R. E. Arias, J. Fineberg
Summary: The rupture dynamics of the interface joining two materials under frictional contact is significantly influenced by the mechanical properties of the bulk materials that bound the interface. When the materials are similar, Linear Elastic Fracture Mechanics quantitatively describe the rupture, but when the elastic properties differ, bimaterial coupling effects come into play. The study shows that at low rupture velocities, bimaterial cracks described by LEFM govern the interface rupture, but as velocities increase, bimaterial cracks become unstable at a subsonic critical rupture velocity.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Geochemistry & Geophysics
Shahar Gvirtzman, Jay Fineberg
Summary: Frictional interfaces become unstable due to earthquake-like ruptures, which are similar to shear cracks. The nucleation of rupture determines the onset of friction and it is influenced by local stress and contact area topography. Nucleation events occur as 2D patches that expand at low velocities and are affected by the local stress level.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Chemistry, Physical
Yosyf Piskozub, Heorhiy Sulym
Summary: The proposed numerical-analytical approach addresses the stress-strain state of bimaterial structures with interphase ribbon-like deformable inhomogeneities under combined force and dislocation loading. It considers the possibility of delamination along the inclusion-matrix interface with dry friction and constructs a structurally modular method of jump functions to handle nonlinear properties of thin inclusions. The system of equations and iterative algorithm developed aim to determine friction-slip zones and investigate the influence of loading parameters and friction coefficient.
Article
Multidisciplinary Sciences
Anna Pomyalov, Fabian Barras, Thibault Roch, Efim A. Brener, Eran Bouchbinder
Summary: This article presents a theoretical study on slip pulses in realistic rate- and state-dependent frictional systems. The research shows that slip pulses are inherently unstable objects, but their dynamical evolution is closely linked to their stable counterparts. The study also reveals that slip pulses exist on a steady-state line and their non-steady dynamics are controlled by a single slow unstable mode. This theoretical picture is supported by large-scale simulations.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Geochemistry & Geophysics
Federica Paglialunga, Francois X. Passelegue, Nicolas Brantut, Fabian Barras, Mathias Lebihain, Marie Violay
Summary: The potential energy stored around faults during the inter-seismic period is released during earthquakes in the form of radiated energy, frictional dissipation, and fracture energy. The fracture energy is of primary importance in controlling the initiation, propagation, and arrest of seismic rupture. Seismological estimates of fracture energy show a clear dependence on slip, while recent experimental studies suggest fracture energy as a material property independent of seismic slip. Stick-slip experiments were performed to reconcile these observations and show that near-tip weakening controls rupture initiation, while long-tailed weakening enhances slip during propagation.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Engineering, Mechanical
Wei Lu, Selda Oterkus, Erkan Oterkus, Dagang Zhang
Summary: A two-dimensional peridynamic contact model is proposed to simulate the propagation of frictional crack, contact constraint can be implemented without additional algorithm, and the geometry of the crack can be easily described. The contact force is only related to the stretch of the virtual bond between disconnected material points.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Wen Wang, Qi-Zhi Zhu, Tao Ni, Bozo Vazic, Pania Newell, Stephane P. A. Bordas
Summary: This paper investigates the interaction between crack propagation and interfaces in bimaterial systems through simulated interfacial and subinterfacial fracture behaviors. A modeling approach using the extended bond-based peridynamic model is introduced and validated through a convergence study. The results show that the proposed method satisfactorily captures the interplay between interfaces and crack propagation, and an equilibrium state of mode-I crack growth is successfully obtained in the subinterfacial fracture case.
COMPUTERS & STRUCTURES
(2023)
Article
Geochemistry & Geophysics
Mohamed Abdelmeguid, Ahmed Elbanna
Summary: This study conducts numerical simulations of earthquake and aseismic slip on fault interfaces with dissimilar materials. The results demonstrate that the bimaterial coupling leads to favorable nucleation site and asymmetric rupture propagation. Increasing material contrast enhances this asymmetry, resulting in higher slip rates and normal stress drops. The normal stress drop induced by bimaterial effect can weaken the fault and extend the rupture propagation, leading to increased seismic hazard. These findings underscore the robust characteristics of bimaterial interfaces and suggest further exploration of the role of material contrast in earthquake physics and models of seismic hazard.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
J. Aichele, S. Latour, S. Catheline, P. Roux
Summary: The rupture mechanisms of earthquakes, glacier stick-slips, and landslides are inferred from surface measurements rather than directly observed. Laboratory experiments provide insight into near field effects, which reflect the rupture mechanism but are attenuated in real-world surface data. By using ultrasound speckle correlation, we directly image the elastic wave-field of a nucleating rupture non-invasively in its near-field. Our imaging technique allows us to determine the particle velocity of the shear wave field at the source location and inside the 3D frictional body. We demonstrate that different bimaterial contrasts result in different force mechanisms for pre-rupture microslips and decelerating supershear ruptures, as well as sub-Rayleigh ruptures.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Bo Ra Song, Won Joon Song, Scott E. Johnson, Christopher C. Gerbi, Senthil S. Vel
Summary: Mature faults often separate rocks with different elastic properties, and analyzing the elastic contrast of bimaterial faults is important for understanding earthquake physics and related hazard potential.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Energy & Fuels
Shan Huang, Yiyu Lu, Zhaolong Ge, Zhe Zhou, Yarui Guan, Xuanyi Chen
Summary: The multibranched borehole drilling (MBBD) method uses a self-propelled nozzle (SPN) to create multiple branching boreholes (BBs) in underground mines, which increases the permeability of coal seams and improves the extraction of coal seam gas. This technology has been applied in China with promising results.
Article
Materials Science, Multidisciplinary
Robert C. Viesca
Summary: We investigate the existence of a characteristic length for non-linear interfacial slip instability based on theoretical descriptions of sliding friction. By examining friction laws and their relationship with contact body elasticity, we find that such a length may not always be present. Our analysis of various descriptions of frictional strength reveals that the area required to support slip instability is negligible for laws that align more closely with experimental data. This challenges the notion of a minimum earthquake size and suggests that the nucleation phase of dynamic rupture contains valuable information on the evolution of frictional strength.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Engineering, Geological
Ming Zhang, Long Yang, Weichao Li, Zhengbo Wang, Chenyang Zhang, Qian Chen, Bo Wang
Summary: In this study, we investigated the frictional properties of the rupture surface of the Jiweishan carbonate rock avalanche. High-velocity-friction tests were conducted on limestone and shale samples at different shear rates. We found that the samples exhibited shear-and rate-strengthening of friction at low shear rates, but transformed to shear-and rate-weakening of friction at large shear rates. The critical shear rate was estimated to be between 0.05 and 0.2 m/s. The reduced frictional resistance was attributed to the presence of recrystallized calcite nanograins and CaO nanograins that covered and lubricated the shear surface, as well as the CO2 emitted through calcite decomposition that reduced effective normal stress and friction on the surface. Our findings are applicable to understanding the high mobility of other carbonate rock avalanches.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Mechanics
Yair De-Leon, Chaim I. Garfinkel, Nathan Paldor
Summary: Analytical and numerical solutions of the eigenvalue equation associated with zonally propagating waves of the linearized rotating shallow water equations are derived in a channel on the equatorial beta-plane in the presence of a uniform mean zonal flow. The mean state causes the dispersion curves of each of the free Rossby and Poincare waves to nearly coalesce in pairs of modes when the zonal wavenumber increases. The eigenvalue problem loses its Sturm-Liouville structure for large mean speed and large zonal wavenumber, and the eigenfunctions have multiple extrema between successive zeros of the function itself.
Article
Geochemistry & Geophysics
Rita Touma, Alexandre Aubry, Yehuda Ben-Zion, Michel Campillo
Summary: This study explores a new approach to analyze the distribution of scatterers in fault zones using a reflection matrix method, providing insights into the importance of small-scale heterogeneities for the structural and mechanical models of fault zones. The method allows for the resolution of local intensities and locations of features within fault zones, offering insights into deep rock damage.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Hongrui Qiu, Benxin Chi, Yehuda Ben-Zion
Summary: We conducted high-resolution seismic imaging of the central Garlock fault using data from two dense seismic arrays. The results show that the Garlock fault is a sharp bimaterial interface, with P waves traveling approximately 5% faster in the northern crustal block. This velocity contrast agrees with regional tomography models and generates clear P-wave reflections in recorded waveforms. The findings provide important constraints for further earthquake studies, simulations of ruptures and ground motion, and future imaging research related to the Garlock fault.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Shiqing Xu, Eiichi Fukuyama, Futoshi Yamashita, Hironori Kawakata, Kazuo Mizoguchi, Shigeru Takizawa
Summary: The topographic heterogeneity of faults affects their strength and earthquake properties. Less heterogeneous faults are weaker and have a larger stress drop compared to more heterogeneous faults. Rupture along less heterogeneous faults tends to propagate at subshear speed while more heterogeneous faults accommodate a wider range of rupture speeds. These findings have implications for understanding natural faults and earthquakes.
Article
Geochemistry & Geophysics
Leila Mizrahi, Shyam Nandan, William Savran, Stefan Wiemer, Yehuda Ben-Zion
Summary: This paper proposes a question-driven ensemble (QDE) modeling approach to address the goals of gaining new insights into earthquake physics and producing improved forecasts. Through pseudoprospective forecasting experiments in southern California and Italy, it is found that certain QDE models outperform standard ETAS and ingredient models, effectively addressing the issues in both regions.
SEISMOLOGICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Lei Qin, Hongrui Qiu, Nori Nakata, Sizhuang Deng, Alan Levander, Yehuda Ben-Zion
Summary: High-frequency seismic data on Mars are dominated by wind-generated lander vibrations, which are partially radiated to the subsurface. Autocorrelation functions (ACFs) of seismic data on Mars filtered between 1 and 5 Hz show clear phases at around 1.3, 2.6, and 3.9 seconds. Daily changes in arrival times correlate well with ground temperature changes, exhibiting a 5% daily variation and a 50-minute apparent phase delay. Two possible mechanisms are proposed to explain these observations: interference of two predominant spectral peaks at around 3.3 and 4.1 Hz, assumed to be lander resonance modes, and interference of lander vibration and its reflection from an interface approximately 200 meters below the lander. The driving mechanism behind the 50-minute delay is likely thermoelastic strain affecting the lander-ground coupling and subsurface structures. The presented methodology and results contribute to the analysis of ACFs with limited data and enhance our understanding of subsurface materials on Mars.
SEISMOLOGICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Yifang Cheng, Egill Hauksson, Yehuda Ben-Zion
Summary: Earthquake focal mechanisms, determined using P-wave polarities and S/P amplitude ratios, are crucial for studying fault zone geometry, slip direction, and crustal stress field. A new convolutional-neural-network algorithm is utilized to detect additional seismic phases and polarities, allowing for a high-quality focal mechanism catalog to be built. This new catalog provides valuable insights into the crustal stress field, earthquake triggering mechanisms, fault zone geometry, and slip direction in southern California.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Guoliang Li, Yehuda Ben-Zion
Summary: By establishing a baseline of ongoing secular velocity variations at the subsurface, the accuracy of detecting and interpreting short-term velocity changes can be improved, further advancing the understanding of observed seismic motions and the behavior of subsurface materials. In this study, a deconvolved autocorrelation method was developed and applied to estimate regional daily and seasonal changes of seismic velocities in southern California. The results showed widespread daily and seasonal changes in the top tens of meters of the crust, with amplitudes of up to 10% and 4%, respectively. Factors such as surface layer thickness, distance from the coast, and topographic variations were found to control the amplitudes of the resolved velocity variations. Changes in soil moisture and thermoelastic strain were identified as likely dominant factors affecting the daily and seasonal variations, respectively. The developed deconvolved autocorrelation method can enhance the accuracy and robustness of estimated changes of subsurface materials at other locations.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Y. Sheng, A. Mordret, F. Brenguier, P. Boue, F. Vernon, T. Takeda, Y. Aoki, T. Taira, Y. Ben-Zion
Summary: This study proposes a systematic workflow to seek powerful seismic sources for monitoring fault zones' seismic velocity changes. The algorithm is tested in California and Japan, and multiple sites close to fault zones show stable high-frequency correlation functions. These findings have great potential for fault zone monitoring.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
P. -E. Share, F. L. Vernon, Y. Ben-Zion
Summary: Key factors controlling earthquake ruptures include fault geometry, continuity, and seismic velocity structure around the fault. A novel tool is presented to better inform these factors in the San Jacinto fault zone in southern California. The results reveal a continuous bimaterial interface and deep northeast dipping fault segments within the fault zone, with implications for earthquake rupture speed, mode, directivity, and frictional heating.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Chuang Cheng, Dun Wang, Qiang Yao, Lihua Fang, Shiqing Xu, Zihao Huang, Tonghui Liu, Zhifeng Wang, Xiaolin Huang
Summary: We analyzed the Mw 7.3 Madoi, China earthquake sequence that occurred along the low-slip-rate Kunlun Mountain Pass-Jiangcuo Fault (KMPJF) using local and teleseismic seismic data. The relocated earthquakes revealed a complex fault with a length of approximately 170 km, bifurcated ends, and varying dip angles. Backprojection analyses of the mainshock rupture process showed bilateral propagation with maximum speeds of about 4.0 km/s. The spatial correlation between the fast supershear rupture speeds and the geometric complexities of the KMPJF suggested that these transient ruptures are influenced by the varying geometry of the immature fault. Our findings highlight the importance of considering potential supershear ruptures along immature strike-slip faults in earthquake hazard assessment.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geosciences, Multidisciplinary
Shuo Zhang, Bingxu Luo, Yehuda Ben-Zion, David E. Lumley, Hejun Zhu
Summary: Continuous seismic ambient noise can be used to monitor the temporal evolution of near-surface seismic velocity, which provides critical information for water resource management and water deficit estimation. The long-term trend of seismic velocity is negatively correlated with groundwater recharge and discharge, while short-term peaks align with drought index, indicating the potential for monitoring meteorological droughts. The seasonal cycle of seismic velocity can be attributed to thermo-elastic strains driven by atmospheric temperature changes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Hao Zhang, Haoran Meng, Yehuda Ben-Zion
Summary: We used signals from freight trains and trucks to image the shallow seismic structure of the Southern San Andreas Fault (SSAF). Our findings reveal strong lateral variations of Rayleigh wave velocities and Q-values across the SSAF, including a 35% velocity reduction across the Mission Creek Fault (MCF) towards the northeast and strong attenuation around the two fault strands. We also observed a 10% mass density reduction and 45% shear modulus decrease across the MCF.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Jessica McBeck, Benoit Cordonnier, Yehuda Ben-Zion, Francois Renard
Summary: The spatial organization of deformation can provide important information about the timing of catastrophic failure in the brittle regime. Recent analyses show that deformation experiences temporary phases of delocalization superposed on an overall trend of localization. X-ray tomography experiments reveal that larger confining pressure promotes more dilation and greater localization of high strain events, while greater amounts of preexisting damage promote delocalization. Importantly, dilative strain may provide more reliable information about the timing of catastrophic failure than shear strain.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Ellis J. Vavra, Hongrui Qiu, Benxin Chi, Pieter-Ewald Share, Amir Allam, Matthias Morzfeld, Frank Vernon, Yehuda Ben-Zion, Yuri Fialko
Summary: The configuration of the Southern San Andreas Fault at seismogenic depths in the Coachella Valley has been a mystery. By analyzing space geodetic and seismic observations, it has been revealed that the straight southernmost section of the fault is dipping to the northeast, connecting with clusters of seismic activity. This dipping fault geometry has significant implications for fault slip rate, ground shaking intensity, and fault strength.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Yehuda Ben-Zion, Georg Dresen
Summary: This study reviews properties and processes of earthquake rupture zones, assesses the dominance of different processes, and evaluates the validity of commonly used models. Different regions of the rupture zone are dominated by various processes, such as fracturing, granulation, and frictional sliding. Wave-mediated stress transfer and spatial discontinuity of earthquake ruptures are also examined.
PURE AND APPLIED GEOPHYSICS
(2022)
