Preprints
Search for earthquake (503 results)
Bayesian inference on the initiation phase of the 2014 Iquique, Chile, earthquake
Published: 2022-10-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We investigate the initiation phase of the 2014 Mw8.1 Iquique earthquake in northern Chile. In particular, we focus on the month preceding the mainshock, a time period known to exhibit an intensification of the seismic and aseismic activity in the region. The goal is to estimate the time-evolution and partitioning of seismic and aseismic slip during the preparatory phase of the mainshock. To do [...]
Tsunami Early Warning from Global Navigation Satellite System Data using Convolutional Neural Networks
Published: 2022-09-29
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Oceanography
We investigate the potential of using Global Navigation Satellite System (GNSS) observations to directly forecast full tsunami waveforms in real time. We train convolutional neural networks (CNNs) to use less than 9 minutes of GNSS data to forecast the full tsunami waveforms over 6 hours at select locations, and obtain accurate forecasts on a test dataset. Our training and test data consists of [...]
Complex evolution of the 2016 Kaikoura earthquake revealed by teleseismic body waves
Published: 2022-09-23
Subjects: Physical Sciences and Mathematics
The 2016 Kaikoura earthquake, New Zealand, ruptured more than a dozen faults, making it difficult to prescribe a model fault for analysing the event by inversion. To model this earthquake from teleseismic records, we used a potency density tensor inversion, which projects multiple fault slips onto a single model fault plane, which reduced the non-uniqueness due to the uncertainty in selecting the [...]
Rapid fault healing after seismic slip
Published: 2022-09-01
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
Fault strength recovery (healing) following an earthquake is a key process in controlling the recurrence of future events; however, the rates and mechanisms of fault healing are poorly constrained. Here, by performing high-velocity friction experiments at seismic slip rates (0.57 m/s), we show that granite and gabbro fault gouges recover their strength rapidly after experiencing dynamic [...]
Double surface rupture and hydraulic recharge of a three-fault system during the Mw 4.9 earthquake of 11 November 2019 at Le Teil (France)
Published: 2022-08-08
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Numerical Analysis and Scientific Computing
The Mw 4.9 earthquake of 11 November 2019 at Le Teil (France) occurred at a very shallow depth (about 1 km) inducing the surface rupture of La Rouvière fault, nearby of a limestone quarry. Thanks to satellite differential interferometry, we detected the existence of the secondary surface rupture of the quasi-parallel Bayne Rocherenard fault. A newly processed seismic cross-section allowed us to [...]
Estimating the Occurrence of Slow Slip Events and Earthquakes with an Ensemble Kalman Filter
Published: 2022-08-07
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
Our ability to forecast earthquakes and slow slip events is hampered by limited information on the current state of stress on faults. Ensemble data assimilation methods permit estimating the state by combining physics-based models and observations, while considering their uncertainties. We employ an Ensemble Kalman Filter (EnKF) to estimate shear stresses, slip rates, and the state theta acting [...]
A High-order Accurate Summation-by-Parts Finite Difference Method for Fully-dynamic Earthquake Sequence Simulations within Sedimentary Basins
Published: 2022-08-06
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
We present a computationally efficient numerical method for earthquake sequences that incorporates wave propagation during rupture. A vertical strike-slip fault governed by rate-and-state friction is embedded in a heterogeneous elastic half-space discretized using a high-order accurate Summation-by-Parts finite difference method. We develop a two solver approach: Adaptive time-stepping is [...]
Within the subducting Nazca Plate: The 2020 Mw 6.8 Calama earthquake and its similarity with the surrounding inslab seismicity
Published: 2022-08-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We study the 2020 MW 6.8 Calama earthquake sequence that occurred within the subducting oceanic Nazca plate. The mainshock is modeled via waveform inversion using a dynamic rupture model, while detection and location techniques are used to better characterize its aftershock sequence. We analyze the local seismotectonic and thermal context of the subducting Nazca plate to understand the trigger [...]
Resolving minute temporal seismic velocity changes induced by earthquake damage: The more stations, the merrier ?
Published: 2022-07-29
Subjects: Earth Sciences, Geophysics and Seismology
Ground shaking induced by earthquakes often introduces transient changes in seismic velocity monitored with ambient noise. These changes are usually attributed to relaxation behavior following the co-seismic damage in the subsurface and are of relevance for postseismic hazard mitigation. However, the velocity evolution associated with this phenomenon can occur at very small timescales and [...]
Comparison of methods for coupled earthquake and tsunami modeling
Published: 2022-07-09
Subjects: Geophysics and Seismology
Tsunami generation by offshore earthquakes is a problem of scientific interest and practical relevance, and one that requires numerical modeling for data interpretation and hazard assessment. Most numerical models utilize two-step methods with one-way coupling between separate earthquake and tsunami models, based on approximations that might limit the applicability and accuracy of the resulting [...]
Harnessing Distributed Acoustic Sensing for Earthquake Early Warning: Magnitude Estimation and Ground Motion Prediction
Published: 2022-06-22
Subjects: Geophysics and Seismology
Earthquake Early Warning (EEW) systems provide seconds to tens of seconds of warning time before potentially-damaging ground motions are felt. For optimal warning times, seismic sensors should be installed as close as possible to expected earthquake sources. However, while the most hazardous earthquakes on Earth occur underwater, most seismological stations are located on-land; precious seconds [...]
Friction law for earthquake nucleation: size doesn’t matter
Published: 2022-06-17
Subjects: Geology, Geophysics and Seismology
A central question in modeling induced and natural earthquake nucleation is whether fault frictional properties measured in the laboratory are applicable to nature. A laboratory fault is generally just a few centimeters in length-width scale, while natural faults can be hundreds of meters to kilometers in extent. It is unknown whether laboratory fault friction data are applicable even to mesh [...]
The Mechanisms of Tsunami Amplification and the Earthquake Source of the 2021 M7 Acapulco, Mexico, Earthquake
Published: 2022-06-02
Subjects: Earth Sciences, Physical Sciences and Mathematics
Here we show a slip model for the 2021 M7 Acapulco, Mexico, earthquake produced by inversion of strong motion, GNSS, tide gauge, and InSAR data. The earthquake occurs within the Guerrero gap, identified as a region of concern for its seismogenic potential and paucity of large events. We find that rupture was compact, constrained to depths between 10 and 20 km and consistent of two main slip [...]
Space-time landslide hazard modeling via Ensemble Neural Networks
Published: 2022-06-02
Subjects: Applied Statistics, Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Statistics and Probability
For decades, a full numerical description of the spatio-temporal dynamics of a landslide could be achieved only via physics-based models. The part of the geomorphology community focusing on data-driven model has instead focused on predicting where landslides may occur via susceptibility models. Moreover, they have estimated when landslides may occur via models that belong to the [...]
Foraminifera as a tool for the reconstruction of paleobathymetry and geohazard: A case study from Taiwan
Published: 2022-06-02
Subjects: Earth Sciences
The calcite tests of foraminifera are an important biogenic component of marine sediments. The abundance of foraminiferal tests in marine sediments broadly varies with bathymetry, thus has been used to reconstruct paleobathymetry. It is also promising as a tracer for downslope transport triggered by earthquakes and typhoons, especially if the displaced material from shallow locality contrasts [...]