Preprints
Search for earthquake (513 results)
Seafloor Geodesy Unveils Seismogenesis of Large Subduction Earthquakes in México
Published: 2025-03-26
Subjects: Earth Sciences, Physical Sciences and Mathematics
Seafloor geodesy may lead to deep understanding of subduction systems and seismogenesis. 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 Acapulco, Mexico, earthquake in 2021 at the heart of the Guerrero seismic gap. We exploit unprecedented ocean-bottom [...]
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 [...]
An Enhanced Deep-Learning Catalog of the Mw 8.8 Maule Aftershock Sequence
Published: 2025-03-18
Subjects: Physical Sciences and Mathematics
We re-examine the aftershock sequence of the Mw 8.8 Maule earthquake in south-central Chile using deep learning on 10 months of continuous seismic data from 156 temporary stations along the rupture zone (March 2010–March 2011). By integrating back-projection and matched filtering with PhaseNet (a deep-learning phase picker), we initially identify 99,137 earthquakes. We then relocate these events [...]
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: 2025-02-12
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 [...]
A New Theory of Global Climate and Ecosystem Change Based on Planetary Orbital Variations
Published: 2025-02-05
Subjects: Education, Physical Sciences and Mathematics
Traditional climate change research has primarily focused on internal factors of Earth, particularly the impact of human activities on greenhouse gas emissions. This paper proposes the "Mao's Theory of Global Climate and Ecosystem Change Based on Planetary Orbital Variations", which suggests that changes in Earth's climate and ecosystems are primarily driven by the orbital variations of external [...]
The b value as a strain meter: a comparison of the 1982-1984 and 2005-2024 volcanic unrest at Campi Flegrei - Italy
Published: 2025-02-05
Subjects: Physical Sciences and Mathematics
The Campi Flegrei caldera has experienced several episodes of volcanic unrest during the last few centuries, most notably in 1982-1984 and 2005-present. These periods of unrest are characterized by ground uplift, seismic swarms, and increased degassing. In this study, we compare the seismicity and associated b value variations during the 1982-1984 and 2005-2024 unrest periods. The b value is [...]
Large earthquakes are more predictable than smaller ones
Published: 2025-01-29
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics
Large earthquakes have been viewed as highly chaotic events regardless of their magnitude, making their prediction intrinsically challenging. Here, we develop a mathematical tool to incorporate multiscale physics, capable of describing both deterministic and chaotic systems, to model earthquake rupture. Our findings suggest that the chaotic behavior of seismic dynamics, that is, its sensitivity [...]
DeepGEM-EGF: A Bayesian strategy for joint estimates of source-time functions and empirical Green’s functions
Published: 2025-01-24
Subjects: Earth Sciences
An earthquake record is the convolution of source radiation, path propagation and site effects, and instrument response. Isolating the source component requires solving an ill-posed inverse problem. Whether the instability of inferred source parameters arises from varying properties of the source, or from approximations we introduce in solving the problem, remains an open question. Such [...]
Fingerprinting subduction margins using PCA profiles: A data science approach to assessing earthquake hazard
Published: 2025-01-21
Subjects: Earth Sciences, Statistical Methodology, Statistical Models, Tectonics and Structure
Giant earthquakes (MW ≥ 8.5) along subduction margins pose great hazards to coastal societies. While it is generally accepted that geological margin properties play a role, the controls on giant earthquake occurrence remain undetermined. Their long intermittence times and the comparatively short earthquake record obscure any correlations between margin properties and seismicity. This work [...]