Preprints
Search for earthquake (504 results)
The 2018-2019 seismo-volcanic crisis east of Mayotte, Comoros islands: seismicity and ground deformation markers of an exceptional submarine eruption
Published: 2019-02-28
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
On May 10th, 2018, an unprecedented long and intense seismic crisis started offshore, east of Mayotte, the easternmost of the Comoros volcanic islands. The population felt hundreds of events. Over the course of one year, 32 earthquakes with magnitude greater than 5 occurred, including the largest event ever recorded in the Comoros (Mw = 5.9 on May 15th, 2018). Earthquakes are clustered in space [...]
Can a Raspberry Shake Seismic Network Complement a National Seismic Network? A case study in Haiti
Published: 2019-02-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Complex networks of high-tech sensors are tough to operate and maintain in developing countries – but new low-costs, low-maintenance instruments may help. Because they are “connected objects” they also provide new opportunities to engage the civil society in citizen-science. Here we describe a seismological instrumentation experiment in Haiti with sensors that cost less than 500$ and can be [...]
Bayesian Dynamic Finite-Fault Inversion: 2. Application to the 2016 Mw6.2 Amatrice, Italy, Earthquake
Published: 2019-02-19
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
In 2016 Central Italy was struck by a sequence of three normal faulting earthquakes with moment magnitude (Mw) larger than 6. The Mw 6.2 Amatrice event (08/24) was the first one, causing building collapse and about 300 casualties. The event was recorded by a uniquely dense network of seismic stations. Here we perform its dynamic source inversion to infer the fault friction parameters and stress [...]
Coupled, Physics-based Modeling Reveals Earthquake Displacements are Critical to the 2018 Palu, Sulawesi Tsunami
Published: 2019-02-16
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The September 2018, Mw 7.5 Sulawesi earthquake occurring on the Palu-Koro strike-slip fault system was followed by an unexpected localized tsunami. We show that direct earthquake-induced uplift and subsidence could have sourced the observed tsunami within Palu Bay. To this end, we use a physics-based, coupled earthquake-tsunami modeling framework tightly constrained by observations. The model [...]
Modeling megathrust earthquakes across scales: one-way coupling from geodynamics and seismic cycles to dynamic rupture
Published: 2019-02-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Taking the full complexity of subduction zones into account is important for realistic modelling and hazard assessment of subduction zone seismicity and associated tsunamis. Studying seismicity requires numerical methods that span a large range of spatial and temporal scales. We present the first coupled framework that resolves subduction dynamics over millions of years and earthquake dynamics [...]
Bayesian Dynamic Finite-Fault Inversion: 1. Method and Synthetic Test
Published: 2019-02-12
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Dynamic earthquake source inversions aim to determine the spatial distribution of initial stress and friction parameters leading to dynamic rupture models that reproduce observed ground motion data. Such inversions are challenging, particularly due to their high computational burden, thus so far only few attempts have been made. Using a highly efficient rupture simulation code, we introduce a [...]
An investigation into the role of time-dependent cohesion in interseismic fault restrengthening
Published: 2019-02-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Earthquakes typically exhibit recurrence times that far exceed time-scales attainable in a laboratory setting. To traverse the temporal gap between the laboratory and nature, the slide-hold-slide test is commonly employed as a laboratory analogue for the seismic cycle, from which the time-dependence of fault strength may be assessed. In many studies it is implicitly assumed that all fault [...]
Dynamic Rupture Propagation on Fault Planes with Explicit Representation of Short Branches
Published: 2019-02-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Active fault zones are homes for a plethora of complex structural and geometric features that are expected to affect earthquake rupture nucleation, propagation, and arrest, as well as interseismic deformation. Simulation of these complexities have been largely done using continuum plasticity or scalar damage theories. In this paper, we use a highly efficient novel hybrid finite element-spectral [...]
Effect of fault roughness on aftershock distribution: Plastic off-fault material properties
Published: 2019-02-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We perform spontaneous earthquake rupture simulations on rough strike- slip faults with off-fault plastic material properties. We examine the off-fault stress change and damage pattern resulting from dynamic fault slip in the near-fault region. We use the stress output from each simulation to calculate the Coulomb failure function (CFF). We calculate the CFF values at the extensional side of the [...]
Are U-Th dates correlated with historical records of earthquakes? Constraints from co-seismic carbonate veins within the North Anatolian Fault Zone
Published: 2019-01-22
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
U-Th dating of carbonate veins in connection with active tectonics has recently been used as an attractive tool for constraining the absolute timing of late Quaternary crustal deformations. In this study, for the first time we correlate U-Th ages of travertine deposits in co-seismic fissures along the North Anatolian Fault Zone (NAFZ) with records of Paleoseismological studies supported by [...]
Earthquakes within Earthquakes: Patterns in Rupture Complexity
Published: 2019-01-17
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Earthquake source time functions carry information about the complexity of seismic rupture. We explore databases of source time functions of earthquakes and find that source time functions are composed of distinct peaks that we call subevents. We observe that earthquake complexity, as represented by the number of subevents, grows with earthquake magnitude. We find that subevent magnitudes are [...]
Seismic and aseismic fault growth lead to different fault orientations
Published: 2019-01-10
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Orientations of natural fault systems are subject to large variations. They often contradict classical Andersonian faulting theory as they are misoriented relative to the prevailing regional stress field. This is ascribed to local effects of structural or stress heterogeneities and reorientations of structures or stresses on the long-term. To better understand the relation between fault [...]
Development of an inversion method to extract information on fault geometry from teleseismic data
Published: 2019-01-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Teleseismic waveforms contain information on fault slip evolution during an earthquake, as well as on the fault geometry. A linear finite-fault inversion method is a tool for solving the slip-rate function distribution under an assumption of fault geometry as a single or multiple-fault-plane model. An inappropriate assumption of fault geometry would tend to distort the solution due to Greens [...]
Impulsive source of the 2017, Mw =7.3, Ezgeleh, Iran, earthquake
Published: 2019-01-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
On November 12th 2017, a MW =7.3 earthquake struck near the Iranian town of Ezgeleh, close to the Iran-Iraq border. This event was located within the Zagros fold and thrust belt which delimits the continental collision between the Arabian and Eurasian Plates. Despite a high seismic risk, the seismogenic behaviour of the complex network of active faults is not well documented in this area due to [...]
Wet rice cultivation was the primary cause of the earthquake-triggered Palu landslides
Published: 2019-01-03
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
The death toll and economic impact of an earthquake are greatly exacerbated when landslides are triggered by strong ground motion. These slides typically occur in two different contexts: localized failure of steep slopes that pose a major threat to life in areas below; and lateral spreading of nearly flat sediment plains due to shaking-induced liquefaction, which can damage large areas of [...]