Preprints
Search for earthquake (526 results)
Early warning for great earthquakes from characterization of crustal deformation patterns with deep learning
Published: 2021-02-10
Subjects: Earth Sciences
Although infrequent, large (Mw7.5+) earthquakes can be extremely damaging and occur on subduction and intraplate faults worldwide. Earthquake early warning (EEW) systems aim to provide advanced warning before strong shaking and tsunami onsets. These systems estimate earthquake magnitude using the early metrics of waveforms, relying on empirical scaling relationships of abundant past events. [...]
Increase data sharing or die? An initial view for natural catastrophe insurance
Published: 2021-02-09
Subjects: Earth Sciences, Education, Environmental Sciences, Geography
This article is an illustration of Geography in action, recounting an investigation into an industry's views of data sharing. The insurance sector is fundamentally analytics driven and based on geospatial data. One option for more effective and efficient insurance for natural hazard risks (e.g. flooding, earthquake) is, in theory, to increase the sharing of data between the various [...]
Smooth crustal velocity models cause a depletion of high-frequency ground motions on soil in 2-D dynamic rupture simulations
Published: 2021-02-04
Subjects: Physical Sciences and Mathematics
A depletion of high-frequency ground motions on soil sites has been observed in recent large earthquakes and is often attributed to the nonlinear soil response. Here we show that the reduced amplitudes of high-frequency horizontal-to-vertical spectral ratios on soil can also be caused by a smooth crustal velocity model with low shear wave velocities underneath soil sites. We calculate near-fault [...]
Audible acoustics from low-magnitude fluid-induced earthquakes in Finland
Published: 2021-02-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Earthquakes are frequently accompanied by public reports of audible low-frequency noises. In 2018, public reports of booms or thunder-like noises were linked to induced earthquakes during a Engineered Geothermal System project in the Helsinki Metropolitan area. In response, two microphone arrays were deployed to record and study these acoustic signals while stimulation at the drill site [...]
Shear wave velocity structure beneath North-Western Himalaya and adjoining areas
Published: 2021-01-30
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Shear wave velocity structure, together with Moho depths have been estimated in northwestern Himalaya, Hindu Kush and the Pamirs at a potential resolution of 0.5×0.5 degrees and at 1×1 degrees in the surrounding area, by inverting fundamental mode Rayleigh wave group velocities calculated from regional earthquake (Δ ≤ 2500 km) data, and also from their joint inversions with teleseismic receiver [...]
Was the January 26th, 1700 Cascadia earthquake part of an event sequence?
Published: 2021-01-30
Subjects: Physical Sciences and Mathematics
Coastal subsidence, dating of soil samples and tree rings, and sedimentological evidence of a tsunami point to coseismic activity on a sizable portion of the Cascadia subduction zone circa 1700. Documents from Japan reveal that on January 26th of that year there were tsunami impacts across distant locations in the country and past modeling shows that a large Cascadia earthquake is the most likely [...]
Back-propagating rupture evolution within a curved slab during the 2019 Mw 8.0 Peru intraslab earthquake
Published: 2021-01-28
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The 26 May 2019 Mw 8.0 Peru intraslab earthquake ruptured the subducting Nazca plate where the dip angle of the slab increases sharply and the strike angle rotates clockwise from the epicentre to north. To obtain a detailed seismic source model of the 2019 Peru earthquake, including not only the rupture evolution but also the spatiotemporal distribution of focal mechanisms, we performed [...]
Earthquake-triggered landslide susceptibility in Italy by means of Artificial Neural Network
Published: 2021-01-18
Subjects: Geomorphology
The use of Artificial Neural Network (ANN) approaches has gained a significant role over the last decade in the field of predicting the distribution of effects triggered by natural forcing, this being particularly relevant for the development of adequate risk mitigation strategies. Among the most critical features of these approaches, there are the accurate geolocation of the available data as [...]
Earthquake rupture on multiple splay faults and its effect on tsunamis
Published: 2021-01-16
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Detailed imaging of accretionary wedges reveals splay fault networks that could pose a significant tsunami hazard. However, the dynamics of multiple splay fault activation during megathrust earthquakes and the consequent effects on tsunami generation are not well understood. We use a 2-D dynamic rupture model with complex topo-bathymetry and six curved splay fault geometries constrained from [...]
Landslide size matters: a new spatial predictive paradigm
Published: 2021-01-07
Subjects: Physical Sciences and Mathematics
The standard definition of landslide hazard requires the estimation of where, when (or how frequently) and how large a given landslide event may be. The geomorphological community involved in statistical models has addressed the component pertaining to how large a landslide event may be by introducing the concept of landslide-event magnitude scale. This scale, which depends on the planimetric [...]
Comments on “On the reported magnetic precursor of the 1989 Loma Prieta earthquake” by J.N. Thomas, J.J. Love, and M.J.S. Johnston
Published: 2021-01-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Thomas et al. (2009) (hereafter TLJ09) attempt to cast doubt upon the report by FraserSmith et al. (1990) (hereafter FS90) of unusual large-amplitude ultra-low frequency (ULF; f < 10 Hz) magnetic fields preceding the M ~7 Loma Prieta earthquake. TLJ09 suggest there are instrumental problems with FS90’s data that we, the designers, builders and long-term operators of the equipment, are presumed to [...]
Spectral element modelling of seismic wave propagation in visco-elastoplastic media including excess-pore pressure development
Published: 2021-01-06
Subjects: Earth Sciences, Engineering, Geophysics and Seismology, Geotechnical Engineering
Numerical modelling of seismic wave propagation, considering soil nonlinearity, has become a major topic in seismic hazard studies when strong shaking is involved under particular soil conditions. Indeed, when strong ground motion propagates in saturated soils, pore pressure is another important parameter to take into account when successive phases of contractive and dilatant soil behaviour are [...]
Evaluation of the Grillo sensor, a low-cost accelerometer for IoT-based Real-time seismology
Published: 2021-01-02
Subjects: Geophysics and Seismology
Micro-Electro-Mechanical (MEMS) accelerometers are useful for real-time seismology due to their ability to record strong, unsaturated seismic signals. Recent advances in MEMS technologies enable design of instruments with improved capabilities that also allow recording of small signals. As a result, MEMS can be useful across a broad dynamic range and for both major earthquakes and smaller [...]
The 2020 Mw 6.5 Monte Cristo Range, Nevada earthquake: relocated seismicity shows rupture of a complete shear-crack system
Published: 2020-12-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
The predominant model for earthquake faulting is a shear crack, including surrounding damage zones. Observation of this complete shear crack system at seismogenic depth, however, has been elusive. Shear cracks with damage zones are related to fault formation and growth, and earthquake rupture physics and size, but observational and analytical limitations impede use of the shear crack paradigm in [...]
Bookshelf Kinematics and the Effect of Dilatation on Fault Zone Inelastic Deformation: Examples from Optical Image Correlation Measurements of the 2019 Ridgecrest Earthquake Sequence
Published: 2020-12-17
Subjects: Physical Sciences and Mathematics
The 2019 Ridgecrest earthquake sequence initiated on July 4th with a series of foreshocks, including a Mw 6.4 event, that culminated a day later with the Mw 7.1 mainshock and resulted in rupture of a set of cross-faults. Here we use sub-pixel correlation of optical satellite imagery to measure the displacement, finite strain and rotation of the near-field coseismic deformation to understand the [...]