Preprints
Search for earthquake (502 results)
Implementation of the Peruvian Earthquake Early Warning System
Published: 2024-06-12
Subjects: Artificial Intelligence and Robotics, Geophysics and Seismology
We present the implementation and testing of the seismological components of the Peruvian Earthquake Early Warning System (Sistema de Alerta Sísmica Peruano, SASPe). SASPe is designed to send alert messages to areas located within a given distance from the epicenter of large (magnitude ≥ 6.0) subduction earthquakes, with a first alert based on data available 3 seconds after the arrival [...]
Do large earthquakes start with a precursory phase of slow slip?
Published: 2024-06-06
Subjects: Geophysics and Seismology
In a recent publication, we showed that a stack of all GPS time series recorded before Magnitude ≥ 7.0 earthquakes suggests that large earthquakes start with a precursory phase of accelerating slow slip (Bletery and Nocquet, 2023). While no peer-reviewed comment or publication has formally contradicted this result, informal discussion has emerged on various platforms. We present here the [...]
Ensemble Kalman, Adaptive Gaussian Mixture, and Particle Flow Filters for Optimized Earthquake Forecasting
Published: 2024-06-01
Subjects: Dynamical Systems, Geophysics and Seismology, Other Statistics and Probability
Probabilistic forecasts are regarded as the highest achievable goal when predicting earthquakes, but limited information on stress, strength, and governing parameters of the seismogenic sources affects their accuracy. Ensemble data-assimilation methods, such as the Ensemble Kalman Filter (EnKF), estimate these variables by combining physics-based models and observations.While the EnKF has [...]
Ringing mountain ranges: Teleseismic signature of the interaction of high-frequency wavefields with near-source topography at the Degelen nuclear test site
Published: 2024-05-26
Subjects: Geophysics and Seismology
Over the last decade there has been an international effort to find methods to recover and digitize recordings from historical earthquakes and explosions that occurred during the 1950’s through to the 1980’s. Making these recordings accessible in digital format offers opportunities to study what signatures are encoded in the data, and to apply state-of-the-art techniques and methods to historical [...]
Predictable recovery rates in near-surface materials after earthquake damage
Published: 2024-05-23
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Earthquakes introduce transient mechanical damage in the subsurface, which causes postseismic hazards and can take years to recover. This observation has been linked to relaxation, a phenomenon observed in a wide class of materials after straining perturbations, but its duration after earthquake ground shaking has not been constrained. Here, we analyse the effects of two successive large [...]
Non-typical supershear rupture: fault heterogeneity and segmentation govern unilateral supershear and cascading multi-fault rupture in the 2021 Mw 7.4 Maduo Earthquake
Published: 2024-05-05
Subjects: Geophysics and Seismology
Previous geodetic and teleseismic observations of the 2021 Mw 7.4 Maduo earthquake imply surprising but difficult-to-constrain complexity, including rupture across multiple fault segments and supershear rupture. Here, we present an integrated analysis of multi-fault 3D dynamic rupture models, high-resolution optical correlation analysis, and joint optical-InSAR slip inversion. Our preferred [...]
The linked complexity of coseismic and postseismic faulting revealed by seismo-geodetic dynamic inversion of the 2004 Parkfield earthquake
Published: 2024-04-26
Subjects: Physical Sciences and Mathematics
Several regularly recurring moderate-size earthquakes motivated dense instrumentation of the Parkfield section of the San Andreas fault, providing an invaluable near-fault observatory. We present a seismo-geodetic dynamic inversion of the 2004 Parkfield earthquake, which illuminates the interlinked complexity of faulting across time scales. Using fast-velocity-weakening rate-and-state friction, [...]
An analysis of the dynamic range of Distributed Acoustic Sensing for Earthquake Early Warning
Published: 2024-04-26
Subjects: Geophysics and Seismology
Owing to its deployment and sensing characteristics, Distributed Acoustic Sensing (DAS) has been touted as a promising technology for low-cost and low-latency Earthquake Early Warning (EEW). While preliminary experiments conducted by several research groups have yielded encouraging results, it must be acknowledged that these EEW feasibility studies were performed only on low-magnitude events. [...]
The application of MEMS seismometers to regional-scale passive seismology: a case study of the Sercel WiNG nodes.
Published: 2024-04-24
Subjects: Physical Sciences and Mathematics
Micro ElectroMechanical Systems (MEMS) accelerometers have become increasingly common in geophysical studies. Despite this, no work has been done to assess the suitability of an array of MEMS sensors to low-frequency, regional-scale passive seismic studies. Consequently, a month’s-long deployment of twenty MEMS-based Sercel WING nodes, two Güralp CMG-ESPCDS and one 4.5 Hz geophone-Reftek system [...]
Rapid earthquake-tsunami modeling: The multi-event, multi-segment complexity of the 2024 Mw 7.5 Noto Peninsula Earthquake governs tsunami generation
Published: 2024-04-13
Subjects: Geophysics and Seismology
The January 1st, 2024, moment magnitude (Mw) 7.5 Noto Peninsula earthquake ruptured in complex ways, challenging timely analysis of the tsunami generation. We present rapid and accurate tsunami models informed by a 6-subevent centroid moment tensor (CMT) model that we obtain by inverting teleseismic and strong motion data and validation against geodetic observations. We identify two distinct [...]
Sentinel-1 SAR-based Globally Distributed Landslide Detection by Deep Neural Networks
Published: 2024-04-05
Subjects: Artificial Intelligence and Robotics, Geomorphology
Efficient response to large and widespread multiple landslide events (MLEs) demands rapid and effective landslide detection. Despite extensive efforts using optical remotely sensed imagery, limitations in global, day & night, and all-weather operational capabilities remain. To address these gaps, we introduce an approach that harnesses Deep Neural Networks (DNNs) and Synthetic Aperture Radar [...]
Coral Ba/Ca reflected the past earthquake and tsunami on Kikai Island in 1911
Published: 2024-03-18
Subjects: Geochemistry
Natural disasters like earthquakes and tsunamis significantly affect coral reefs and marine ecosystems. The Ryukyu Islands, including Kikai Island and the surrounding coral reefs, face the potential risk of experiencing a significant earthquake with Mw > 8. While historical records offer insights into past tsunami occurrences, there is scarce observation or quantitative data on the impacts of [...]
Brittle origin of off-fault fractures during the 2019 Ridgecrest earthquake sequence
Published: 2024-03-14
Subjects: Earth Sciences, Geophysics and Seismology, Tectonics and Structure
According to the classical Mohr-Coulomb-Anderson theory, faults form at an angle from the largest regional compressive stress that is approximately 30° for most rocks. However, real settings are more complex and faults often present orientations inconsistent with the angles predicted by the classical theory applied to the present-day regional stress field. The Ridgecrest region hosts a young [...]
A Multiplex Rupture Sequence under Complex Fault Network due to Preceding Earthquake Swarms during the 2024 Mw 7.5 Noto Peninsula, Japan, Earthquake
Published: 2024-03-14
Subjects: Geophysics and Seismology
A devastating earthquake with moment magnitude 7.5 occurred in the Noto Peninsula in central Japan on 1 January 2024. We estimate the rupture evolution of this earthquake from teleseismic P-wave data using the potency-density tensor inversion method, which provides information on the spatiotemporal slip distribution including fault orientations. The results show a long and quiet initial rupture [...]
Assessing the Earthquake Recording Capability of an Ocean-bottom Distributed Acoustic Sensing Array in the Sanriku region, Japan
Published: 2024-03-07
Subjects: Physical Sciences and Mathematics
Sparse seismic instrumentation in the oceans limits our understanding of the Earth’s dynamics. The emerging technology of Distributed Acoustic Sensing (DAS), which can turn existing fiber-optic cable arrays into thousands of seismic sensors, has the potential to fill the data gap. Yet, the power of OBDAS for routine seismic monitoring has to be further explored. In this study, we investigate the [...]