Article
Geosciences, Multidisciplinary
Zijia Wang, Wenqiang Zhang, Tuncay Taymaz, Zhongqiu He, Tianhong Xu, Zhenguo Zhang
Summary: We simulated the dynamic rupture process of the Mw 7.8 Kahramanmaras earthquake in SE Turkiye on 6 February 2023, considering various non-uniformities such as branch faults, rotation of stress field directions, and changes in tectonic environments. Near-fault waveform data, GNSS static displacements, and surface rupture were used to constrain the dynamic model. The results reveal the successful triggering of the East Anatolian Fault (EAF) and supershear rupture in the northeast segment due to high initial stress accumulation in the Kahramanmaras-celikhan seismic gap. The complexity of fault geometry caused the rupture speed along the southeastern segment of the EAF to vary between supershear and subshear, contributing to unexpectedly strong ground motion. The triggering of the EAF highlights the importance of being aware of seismic gaps on major faults being triggered by secondary faults to prevent significant disasters.
GEOPHYSICAL RESEARCH LETTERS
(2023)
News Item
Geosciences, Multidisciplinary
Ryo Okuwaki
Summary: A global investigation has found that faults rupturing faster than seismic waves can travel is more common and destructive than previously believed.
Article
Geosciences, Multidisciplinary
Feng Hu, David D. Oglesby, Baoning Wu, Xiaofei Chen
Summary: Rupture velocity, defined by different gradients, affects the understanding of earthquake physics. In some cases, a rupture may be classified as supershear using a 1D horizontal measure but not via the 2D gradient calculation, highlighting the importance of rupture velocity definitions for supershear analysis.
GEOPHYSICAL RESEARCH LETTERS
(2021)
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
Chao Liang, Jean-Paul Ampuero, Daniel Pino Munoz
Summary: This study investigates for the first time the prevalence of supershear ruptures across multiple earthquake cycles on long faults, finding that supershear events only occur in a specific range of friction parameters that are not commonly observed in laboratory experiments, which may explain the rarity of supershear earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2022)
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
Geosciences, Multidisciplinary
Sara Aniko Wirp, Alice-Agnes Gabriel, Maximilian Schmeller, Elizabeth H. Madden, Iris van Zelst, Lukas Krenz, Ylona van Dinther, Leonhard Rannabauer
Summary: Physics-based dynamic rupture models are used to investigate earthquake slip and its effects on tsunami generation, propagation, and coastal inundation. Different scenarios with varying hypocenter locations and geological structures are simulated, revealing their impacts on tsunami dynamics and coastal inundation.
FRONTIERS IN EARTH SCIENCE
(2021)
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
Multidisciplinary Sciences
Peng Dong, Kaiwen Xia, Ying Xu, Derek Elsworth, Jean-Paul Ampuero
Summary: Earthquakes are destructive natural hazards whose damage capacity is determined by rupture speeds. Traditional dynamic rupture models predict that earthquakes accelerate gradually to the Rayleigh wave speed, with some of them reaching stable supershear speeds. However, the 2018 Palu earthquake challenges this viewpoint by demonstrating subRayleigh or supershear propagation speeds immediately after nucleation. Laboratory experiments on shear ruptures and self-similar analysis confirm this observation, leading to a model where rupture speed is solely dependent on driving load. These findings explain various field observations on earthquake speeds.
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
A. Gounon, S. Latour, J. Letort, S. El Arem
Summary: This study experimentally explores the effects of fault heterogeneity on rupture nucleation, revealing a complex nucleation process characterized by an alternation of slow and fast episodes. The study also highlights the large variability in the rupture process due to uncontrolled stress heterogeneity.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Jiankuan Xu, Zhenguo Zhang, Xiaofei Chen
Summary: The thickness and wave velocity of sediments play key roles in determining whether a rupture accelerates into supershear, with deep hypocenters favoring supershear rupture. Additionally, a multi-layered sediment model makes it easier to trigger supershear rupture in higher-velocity sediment.
Article
Multidisciplinary Sciences
Meng Wang, Songlin Shi, Jay Fineberg
Summary: Brittle materials were conventionally believed to have crack propagation speeds limited by the Rayleigh wave speed. However, our experimental study on brittle neo-hookean materials shows the existence of supershear tensile cracks, which can surpass the shear wave speed and even approach the dilatation wave speed. The dynamics of supershear cracks are controlled by different principles compared to classical cracks and this nonclassical fracture mode occurs at critical strain levels specific to the material, representing a fundamental shift in our understanding of fracture processes.
Article
Geochemistry & Geophysics
Jon B. Fletcher, Jemile E. Erdem, Lawrence M. Baker
Summary: This study inverted records from 24 stations to determine the slip and rupture time of an M4.5 aftershock of the 2019 Ridgecrest earthquake sequence. The slip was determined using source time functions, which showed a longer duration in the southeast direction and a shorter duration in the northwest direction, suggesting rupture directivity to the northwest. The study also found that the rupture velocity increased from nucleation to the peak in slip and then slowed down.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Roey Shimony, Zohar Gvirtzman, Michael Tsesarsky
Summary: The Dead Sea Transform dominates seismicity in Israel and neighboring countries, with the potential for a strong earthquake in northern Israel. Ground motions in the region are influenced by the strike-slip basins, with factors such as rupture location, lithology, and local basin structure affecting the behavior and intensity of ground motions. Strike-slip basins can amplify ground motions within, leading to stronger and prolonged regional ground motions due to resonant chamber effects.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2021)
Article
Geosciences, Multidisciplinary
Kanghua Zhang, Yishuo Zhou, Yimin Liu, Pu Wang
Summary: This study investigates the in-situ stress field and fault geometry in the Palu earthquake, and simulates the dynamic rupture process to find the key factors causing supershear rupture. It provides an explanation for the enlarged damage zones and rupture mode in Palu City.
GEOMATICS NATURAL HAZARDS & RISK
(2022)
Article
Geochemistry & Geophysics
Hiroyuki Goto, Yoshihiro Kaneko, Muriel Naguit, John Young
Summary: This study investigates the cause of large asymmetric vertical accelerations (AsVAs) recorded during the 2011 Christchurch earthquake. The results suggest that the AsVAs may be contaminated by nonlinear soil-structure interaction, and placing seismic sensors closer to the center of a foundation slab can mitigate this phenomenon. The analytical procedure introduced in this study may help identify the occurrence of AsVAs and assess whether they are caused by nonlinear soil-structure interaction in other locations.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2021)
Article
Geochemistry & Geophysics
Dongdong Yao, Zhigang Peng, Yoshihiro Kaneko, Bill Fry, Xiaofeng Meng
Summary: Large earthquakes can trigger various types of seismic responses in different regions, leading to dynamic stress perturbations and changes in seismicity rates. Understanding these triggering patterns and susceptibilities is crucial for time-dependent earthquake forecasting.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Jamie D. Howarth, Alan R. Orpin, Yoshihiro Kaneko, Lorna J. Strachan, Scott D. Nodder, Joshu J. Mountjoy, Philip M. Barnes, Helen C. Bostock, Caroline Holden, Katie Jones, M. Namik Cagatay
Summary: Turbidite paleoseismology has provided detailed insights into the relationship between earthquake source, ground motions, and deposition of coseismic turbidites, as demonstrated by measurements from turbidites triggered by the 2016 Kaikoura earthquake in New Zealand.
Article
Geosciences, Multidisciplinary
Andrea Perez-Silva, Duo Li, Alice-Agnes Gabriel, Yoshihiro Kaneko
Summary: In the Guerrero Seismic Gap, Mexico, quasi-periodic long-term slow slip events (SSEs) of magnitude up to M(w)7.5 occur about every 4 years. The flat-slab segment of the Cocos plate contributes to the large magnitudes and long recurrence interval of these SSEs. The 3D slab geometry is crucial in enhancing our understanding of the physics of slow slip events.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Bryant Chow, Yoshihiro Kaneko, Carl Tape, Ryan Modrak, Nick Mortimer, Stephen Bannister, John Townend
Summary: This study uses earthquake-based adjoint tomography to analyze the three-dimensional structure of the North Island and the adjacent Hikurangi subduction zone in New Zealand. The research reveals the material properties and velocity changes associated with the active subduction zone. The results also provide valuable insights into the geology and tectonic structures of the study area, especially in relation to the Hikurangi subduction zone.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Andrea Perez-Silva, Yoshihiro Kaneko, Martha Savage, Laura Wallace, Duo Li, Charles Williams
Summary: Research has found that shallow slow slip events (SSEs) along the Hikurangi subduction zone in New Zealand show a strong along-strike segmentation in their recurrence intervals. Numerical simulations suggest that along-strike changes in both the plate convergence rate and the downdip width of the SSE source region contribute to this segmentation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Bryant Chow, Yoshihiro Kaneko, John Townend
Summary: Seamounts as seafloor heterogeneities affect slip behavior on megathrusts. In the Hikurangi subduction zone, previously unidentified deeply subducted seamounts are inferred from high-resolution velocity models, influencing seismicity and slow slip events. This study suggests that repeated seamount subduction may permanently damage the upper plate and impact plate coupling along the subduction interface.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geosciences, Multidisciplinary
Yoshihiro Kaneko, Hiroyuki Goto
Summary: By studying the data from the 2016 Kumamoto earthquake, it is found that large, long-period ground motions in surface-breaking earthquakes are caused by the dynamic interaction between propagating rupture and the Earth's surface, posing significant hazards to tall buildings and large infrastructures.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
P. A. Inchin, J. Aguilar Guerrero, J. B. Snively, Y. Kaneko
Summary: Simulations were conducted to study the effects of infrasonic acoustic waves on mesopause airglow disturbances. The results suggest that observations of these disturbances can supplement the study of fault kinematics during earthquakes.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Geography, Physical
J. M. Carey, J. J. Mountjoy, G. J. Crutchley, D. N. Petley, C. F. Holden, Y. Kaneko, K. Huhn
Summary: Although subaqueous slopes on active continental margins can have different failure styles, the movement mechanisms during earthquakes are poorly understood due to limited direct sampling of submarine landslides for detailed investigation. This study conducted dynamic shear experiments on samples recovered from the Tuaheni Landslide Complex off the coast of New Zealand to explore its behavior during earthquakes. The experiments suggest that episodic landslide movement can occur through basal sliding when pore water pressures increase, leading to a lower shear zone effective stress. This provides a credible mechanism for subaqueous landslides on low angled shear zones to undergo episodic movement during earthquakes without catastrophic failure.
Article
Astronomy & Astrophysics
Aditya Riadi Gusman, Jean Roger, William Power, Bill Fry, Yoshihiro Kaneko
Summary: A tsunamigenic earthquake occurred in the Loyalty Islands, New Caledonia on February 10, 2021. The tsunami generated by this earthquake was observed in surrounding islands and New Zealand. Researchers used tsunami waveforms to estimate the fault slip distribution and evaluated two tsunami forecasting approaches. The results showed that the pre-computed scenarios and interpolated scenarios matched the observed threat levels in most coastal regions.
EARTH AND SPACE SCIENCE
(2022)
Article
Geochemistry & Geophysics
Brittany A. Erickson, Junle Jiang, Valere Lambert, Sylvain D. Barbot, Mohamed Abdelmeguid, Martin Almquist, Jean-Paul Ampuero, Ryosuke Ando, Camilla Cattania, Alexandre Chen, Luca Dal Zilio, Shuai Deng, Eric M. Dunham, Ahmed E. Elbanna, Alice-Agnes Gabriel, Tobias W. Harvey, Yihe Huang, Yoshihiro Kaneko, Jeremy E. Kozdon, Nadia Lapusta, Duo Li, Meng Li, Chao Liang, Yajing Liu, So Ozawa, Andrea Perez-Silva, Casper Pranger, Paul Segall, Yudong Sun, Prithvi Thakur, Carsten Uphoff, Ylona van Dinther, Yuyun Yang
Summary: Numerical modeling of earthquake dynamics requires credible and reproducible model results. The SEAS initiative aims to facilitate code comparisons and advance physics-based earthquake models. New benchmark problems have been used to explore physical ingredients and numerical considerations in earthquake modeling.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Geochemistry & Geophysics
T. Aoki, Y. Kaneko, J. Kearse
Summary: Understanding the directions of rupture propagation in earthquakes is crucial for studying earthquake physics and assessing seismic hazard. Recent research has found a relationship between the direction of rupture propagation and the curvature of slickenlines formed during seismic slip. However, observations of slickenlines on geometrically complex fault segments often show "abnormal convexity," which can be explained by simulations of spontaneous earthquake ruptures on non-planar and rough faults. These findings emphasize the importance of carefully interpreting slickenlines and focusing on structurally simple parts of faults in investigating rupture directions using curved slickenlines.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geology
Matthew C. Gerstenberger, David A. Rhoades, Nicola Litchfield, Elizabeth Abbott, Tatiana Goded, Annemarie Christophersen, Russell J. Van Dissen, Stephen Bannister, David Barrell, Zane Bruce, Bill Fry, Ian Hamling, Caroline Holden, Nick Horspool, Anna E. Kaiser, Yoshi Kaneko, Robert M. Langridge, Timothy A. Little, Biljana Lukovic, Sara K. McBride, Graeme H. McVerry, Andy Nicol, Nick Perrin, Jarg Pettinga, Mark W. Stirling, Chris Van Houtte, Laura Wallace
Summary: Following the 2016 Kaikoura earthquake, a time-varying seismic hazard model (KSHM) was developed to assist in the reinstatement of road and rail networks. The model combines a gridded earthquake clustering model and an updated fault source model. The fault source model includes newly discovered faults and updated probabilities of rupture for four fault segments. Multiple ground motion prediction equations account for uncertainties in source modeling using a logic tree approach.
NEW ZEALAND JOURNAL OF GEOLOGY AND GEOPHYSICS
(2023)
Article
Geochemistry & Geophysics
Andrea Perez-Silva, Yoshihiro Kaneko, Martha Savage, Laura Wallace, Emily Warren-Smith
Summary: Geophysical observations suggest that pore fluid pressure changes correlate with slow slip events (SSEs) at certain subduction zones. By developing numerical models and varying the characteristics of pore pressure perturbations, the researchers were able to reproduce the properties of SSEs observed in different subduction zones. The study suggests that large permeability values in the shear zone where SSEs occur are needed to explain the observed SSE properties.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
