Preprints
Search for earthquake (526 results)
3D wave propagation and earthquake dynamic rupture simulations in complex poroelastic media
Published: 2024-09-26
Subjects: Geophysics and Seismology
Numerical simulations of earthquakes and seismic wave propagation require accurate material models of the solid Earth. In contrast to purely elastic rheology, poroelasticity accounts for pore fluid pressure and fluid flow in porous media. Poroelastic effects can alter both the seismic wave field and the dynamic rupture characteristics of earthquakes. For example, the presence of fluids may affect [...]
Regional Source-type Discrimination Using Nonlinear Alignment Algorithms
Published: 2024-09-26
Subjects: Physical Sciences and Mathematics
The discrimination problem in seismology aims to accurately classify different underground source types based on local, regional and/or teleseismic observations of ground motion. Typical discriminant approaches are rooted in fundamental, physics-based differences in radiation pattern or wave excitation, which can be frequency dependent and may not make use of the full waveform. In this paper, we [...]
Normal fault interactions in seismic cycles and the impact of fault network geometry
Published: 2024-09-26
Subjects: Physical Sciences and Mathematics
Understanding the mechanisms behind the characteristics of earthquake cycles on normal faults is challenging due to their long recurrence times. Despite their moderate magnitude, normal faulting earthquakes can produce considerable damage. We investigate the effects of fault network geometry and spacing on the seismic cycle of a system of two normal faults modelled with rate-and-state friction [...]
Comparative Analysis of Earthquake Detection Methods Using Deep Learning: Reproducibility and Uncertainty Assessment in EQTransformer
Published: 2024-09-18
Subjects: Physical Sciences and Mathematics
This study evaluates the performance and reliability of earthquake detection using the EQTransformer, a novel AI program that is widely used in seismological observatories and research for enhancing earthquake catalogs. We test the EQTransformer capabilities and uncertainties using seismic data from the Volcanological and Seismological Observatory of Costa Rica and compare two detection options: [...]
Evidence supporting a broader than previously thought influence of solar activity over Earth system’s processes. Discussion of a possible mechanism.
Published: 2024-09-08
Subjects: Atmospheric Sciences, Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Tectonics and Structure, Volcanology
In this article, I show lines of evidence supporting a modulation of volcanic activity and some weather phenomena by solar wind conditions in the near-Earth environment. On a daily timescale, a correlation is found between the LP earthquake activity of Kilauea volcano, related to magma transport, and the Bx component of the interplanetary magnetic field as measured in the OMNI database for [...]
A probabilistic model for coseismic vertical displacement hazard in coastal settings
Published: 2024-09-05
Subjects: Earth Sciences
Characterizing coastal multi-hazards in tectonically active regions requires considering possible coseismic vertical deformation. Coseismic uplift or subsidence can cause near-instantaneous meter-scale relative sea level changes that can exacerbate or reverse the effects of ongoing global sea-level rise. In this study, we developed a probabilistic model that forecasts coseismic vertical [...]
Were the Newdigate Earthquakes, Southern England, of 2018-2019 triggered by oil extraction?
Published: 2024-08-30
Subjects: Physical Sciences and Mathematics
The ability to attribute earthquakes to specific causes is challenging. The 2018-2019 earthquake swarm in Newdigate, Surrey, Southern England, coincides with local oil extraction at Horse Hill. Nevertheless, it remains debated whether these earthquakes were triggered by oil extraction or whether they were coincidental. Due to the onset of seismic activity before major oil extraction and the lack [...]
Physical Mechanisms of Earthquake Nucleation and Foreshocks: Cascade Triggering, Aseismic Slip, or Fluid Flows?
Published: 2024-08-30
Subjects: Physical Sciences and Mathematics
Earthquakes are caused by the rapid rupture of their seismogenic faults. Whether large or small, there is inevitably a certain nucleation process involved before the dynamic rupture. At the same time, although not very common, significant foreshock activity has been observed before some large earthquakes. Understanding the nucleation process and foreshocks of earthquakes, especially large [...]
Towards a widely applicable earthquake detection algorithm for fibreoptic and hybrid fibreoptic-seismometer networks
Published: 2024-08-30
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Distributed Acoustic Sensing (DAS) is a promising technology for providing dense (metre-scale) sampling of the seismic wavefield. However, harnessing this potential for earthquake detection with accurate phase picking and associated localisation remains challenging. Single-channel algorithms are limited by individual channel noise, while machine learning and semblance methods are typically [...]
Rupture Dynamics and Near-Fault Ground Motion of the Mw7.8 Kahramanmaraş, Turkey earthquake of February 6, 2023
Published: 2024-08-28
Subjects: Physical Sciences and Mathematics
We studied the dynamic rupture propagation of the February 6th, 2023 (Mw7.8, 01:17 UTC) Pazarcık (Kahramanmaraş), Turkey, earthquake by incorporating the non-planar fault structure, the regional stress field, and a data-driven friction parameterization into numerical simulations. To explain the rupture extent of 200 km and the average speed, a regional non-uniform load is necessary and was [...]
Localized west-dipping seismic structure defines the Elgin-Lugoff Swarm Sequence in South Carolina
Published: 2024-08-28
Subjects: Education, Physical Sciences and Mathematics
An unusual earthquake swarm began in December 2021 between the towns of Elgin and Lugoff in South Carolina, United States. This area is characterized by historically low seismicity, but by April 2024 it has experienced 97 small earthquakes listed in the United States Geological Survey (USGS) catalog, presenting a unique opportunity to investigate the dynamics of earthquake swarms in stable [...]
Frictional Properties of Simulated Fault Gouges subject to Normal Stress Oscillation and Implications for Induced Seismicity
Published: 2024-08-24
Subjects: Geophysics and Seismology, Oil, Gas, and Energy, Risk Analysis
Under critical conditions where experimental fault slip exhibits self-sustained oscillation, effects of normal stress oscillation (NSO) on fault strength and stability remain poorly understood, as do potential effects of NSO on natural and induced seismicity. In this study, we employed double direct shear testing to investigate the frictional behavior of a synthetic, slightly velocity-weakening [...]
The Origin of Forearc Depressions
Published: 2024-08-23
Subjects: Earth Sciences, Geology, Sedimentology, Tectonics and Structure
Forearc depressions form over continental subduction zones with young, slowly subducting slabs and thick trench fills. They are bound seaward by a coast range and landward by a volcanic arc such that subsidence in forearc depressions occurs between orogens and in areas characterized by plate convergence. We propose a model for forearc depression formation based on geophysical and seismic data [...]
Complex and confined laboratory ruptures explain scaling of the critical slip distance for earthquake faulting
Published: 2024-08-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Earthquake sequences in nature are complex, exhibiting a range of magnitudes and slip behaviors. In contrast, earthquake-like instabilities generated on frictional faults in the laboratory and in continuum numerical models are usually quasi-periodic with a smaller range of magnitudes and durations. The discrepancy, especially apparent for cm-sized samples used in lab friction experiments, has [...]
Partial ruptures governed by the complex interplay between geodetic slip deficit, rigidity, and pore fluid pressure in 3D Cascadia dynamic rupture simulations
Published: 2024-08-14
Subjects: Geophysics and Seismology
Physics-based simulations are crucial to assessing the seismic hazard in the Cascadia subduction zone (CSZ), requiring assumptions about fault stress and material properties. Geodetic slip deficit models (SDMs) may inform the initial stresses governing megathrust earthquake dynamics. We present a unified workflow linking SDMs to 3D dynamic rupture simulations, and 22 rupture scenarios to unravel [...]