Preprints
Search for earthquake (578 results)
A New Fault Model for the 1933 Long Beach Earthquake, Long Beach Area, Southern California
Published: 2025-04-05
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
Newly identified thrust faults and their corresponding thrust sheets, combined with recent micro-earthquake epicenters, better explain anomalous rupture data observed during the 1933 Long Beach Earthquake than previous models based exclusively on Newport-Inglewood Fault Zone strike-slip faulting. A high-quality 45 km2 3D seismic dataset was recorded in 2017, centered along the Seal Beach [...]
Multiple scattering of seismic waves in a heterogeneous magmatic system and spectral characteristic of long period volcanic earthquakes
Published: 2025-04-03
Subjects: Physical Sciences and Mathematics
Long-Period (LP) volcanic earthquakes are characterized by a relatively long duration codas and spectra containing pronounced spectral peaks. These peculiar spectral characteristics are often attributed to source effects, such as resonances of fluid-filled cracks. In this paper, we report the results of numerical simulations of seismic wave propagation showing that the main signal features of the [...]
The complex rupture evolution of the long and slow, tsunamigenic 2021 South Sandwich Islands earthquake
Published: 2025-03-27
Subjects: Geophysics and Seismology
On August 21, 2021 a large earthquake occurred in the South Sandwich subduction zone, and the associated tsunami was widely observed. In order to robustly analyse the detailed seismic source process of this long-source duration (over 200 s) event occurring in a convexly shaped subduction zone, we applied the Potency Density Tensor Inversion with a non-rectangular and non-planar source surface to [...]
Fully-dynamic seismic cycle simulations in co-evolving fault damage zones controlled by damage rheology
Published: 2025-03-26
Subjects: Geophysics and Seismology
Both short-term coseismic off-fault damage and long-term fault growth during interseismic periods have been suggested to contribute to the formation and evolution of fault damage zones. Most previous numerical models focus on simulating either off-fault damage in a single earthquake or off-fault plasticity in seismic cycles ignoring changes of elastic moduli. Here we developed a new method to [...]
Eruption triggering
Published: 2025-03-26
Subjects: Earth Sciences
Volcanic systems behave episodically and require mechanisms for magma segregation, instability and ascent. Here, we discuss the processes that promote the ascent of magma to the Earth's surface and prepare the onset of an eruption, thus acting as triggers, as well as the factors that prevent eruption. We describe the various petrological, geochemical and geophysical observations that reveal the [...]
Seafloor Geodesy Unveils Seismogenesis of Large Subduction Earthquakes in Mexico
Published: 2025-03-25
Subjects: Earth Sciences, Physical Sciences and Mathematics
Based on measurements of near-trench deformations of the oceanic and overriding plates, in this investigation, we elucidate the tectonic and mechanical processes leading to the Mw7.0 (moment magnitude of 7.0) Acapulco, Mexico, earthquake in 2021. We exploit unprecedented ocean-bottom observations using ultralong-period “tilt mechanical amplifiers,” along with hydrostatic pressure, global [...]
Frequency-dependent seismic radiation process of the 2024 Noto Peninsula earthquake from teleseismic P-wave back-projection
Published: 2025-03-25
Subjects: Earth Sciences
A large devastating earthquake of Mw 7.5 struck the Noto Peninsula, Japan, on January 1st, 2024. Persistent seismic swarms have preceded the main rupture around the hypocenter since 2020, likely driven by crustal fluids migrating upward from the lower crust. In this study, we investigated the frequency-dependent seismic radiation process using multi-frequency teleseismic P-wave back projection. [...]
Consideration of rupture kinematics increases tsunami amplitudes in far-field hazards assessments
Published: 2025-03-25
Subjects: Physical Sciences and Mathematics
Tsunamis are large surges of sea water caused by undersea earthquakes. To prepare for future tsunamis, scientists run computer simulations to estimate how big the waves might be and how often they could happen. These simulations are used to make maps and design buildings that can withstand tsunami impacts. Most of these models assume that when an earthquake breaks a fault this happens all at [...]
Fine-scale Segmentation and Spatiotemporal Variability of the 2010 Mw 8.8 Maule Aftershock Sequence Revealed by a Deep-Learning-Based Earthquake Catalog
Published: 2025-03-17
Subjects: Physical Sciences and Mathematics
We re-examine the aftershock sequence of the Mw 8.8 Maule earthquake in south-central Chile to understand how seismicity, magnitude-frequency distribution, and fault structure vary along the rupture zone. Using the International Maule Aftershock Deployment (IMAD) dataset, we analyze ten months of continuous data from 156 temporary stations and build a high-resolution aftershock catalog for the [...]
Seismic imaging of mid-crustal heterogeneity beneath geothermal systems, central Taupo Volcanic Zone, New Zealand
Published: 2025-02-26
Subjects: Earth Sciences, Geophysics and Seismology
The Taupo Volcanic Zone (TVZ) in New Zealand is a region of highly pro- ductive Quaternary volcanism and very large hydrothermal heat flux. Here we investigate the upper- and mid-crustal seismic velocity structure of a region within the central, rhyolitic part of the TVZ encompassing the high- temperature geothermal systems Mokai, Wairakei, Ng¯a Tamariki, Orakei Korako, Te Kopia and Rotokawa. [...]
Using fracture-scarp lineations as kinematic indicators on active normal fault scarps
Published: 2025-02-21
Subjects: Engineering, Physical Sciences and Mathematics
Reliable kinematic (slip vector) data collected from offset piercing points, corrugations or striations, is a key input for fault based seismic hazard assessments. However, it can be difficult to interpret kinematic indicators on degraded fault scarps. In this work, we investigate the orientations and growth history of on-fault fracture networks, which extend into the footwall and have greater [...]
Positive isotropic components of the 2025 Santorini-Amorgos earthquakes
Published: 2025-02-21
Subjects: Physical Sciences and Mathematics
We used full waveforms of the Hellenic Unified Seismic Network (HUSN) regional stations and a frequency range of 0.03-0.06 Hz. We calculated full moment tensors (MTs) and focused on their ISO and CLVD components. In the tested depth range of 1-20 km, the medians of ISO (=VOL) and CLVD are positive, but their 68% confidence intervals are broad due to the tradeoff of the non-DC with depth. When [...]
Positive isotropic components of the 2025 Santorini-Amorgos earthquakes
Published: 2025-02-14
Subjects: Physical Sciences and Mathematics
We used full waveforms of the Hellenic Unified Seismic Network (HUSN) regional stations and a frequency range of 0.03-0.06 Hz. We calculated full moment tensors (MTs) and focused on their ISO and CLVD components. In the tested depth range of 1-20 km, the medians of ISO (=VOL) and CLVD are positive, but their 68% confidence intervals are broad due to the tradeoff of the non-DC with depth. When [...]
Effects of Stress and Friction Heterogeneity on Spatiotemporal Complexity of Seismic and Aseismic Slip on Strike-Slip Faults
Published: 2025-02-12
Subjects: Physical Sciences and Mathematics
Numerical and laboratory models of earthquake cycles on faults governed by rate-and-state friction often show cycle-invariant behavior, while natural faults exhibit considerable variability in slip history. Possible explanations include heterogeneities in fault stress and frictional properties. We investigate how various types of heterogeneity in simulations of quasi-dynamic sequences of seismic [...]
Petrographical evidence of the >1000 km voyage of a white pumice raft that arrived at the Ogasawara and Nansei Islands after the October 2023 earthquakes in the southern Izu Islands
Published: 2025-02-11
Subjects: Volcanology
An earthquake swarm occurred at Sofu Seamount near Izu-Torishima in the Izu-Ogasawara (Bonin) Arc, Japan, on 8 October 2023, followed by the arrival of unexpectedly-large tsunamis over a wide area of the Pacific coast of southwest Japan. On 20 October, aerial observation identified floating pumice rafts extending for ~80 km in the area the seamount, which were subsequently sampled and found to [...]