Preprints
Filtering by Subject: Earth Sciences
Assessing erosion and flood risk in the coastal zone through the application of the multilevel Monte Carlo method
Published: 2021-01-07
Subjects: Applied Mathematics, Earth Sciences, Geomorphology, Hydrology, Numerical Analysis and Computation, Risk Analysis, Statistics and Probability
The risk from erosion and flooding in the coastal zone has the potential to increase in a changing climate. The development and use of coupled hydro-morphodynamic models is therefore becoming an ever higher priority. However, their use as decision support tools suffers from the high degree of uncertainty associated with them, due to incomplete knowledge as well as natural variability in the [...]
Sea-level stability over geologic time owing to limited deep subduction of hydrated mantle
Published: 2021-01-06
Subjects: Earth Sciences
The presence of liquid water makes our planet unique. Its budget over geological timescales, i.e., the long-term global sea level, depends on the balance of water exchanges between the Earth's mantle and the surface through both volcanism (mantle degassing) and subduction of hydrous minerals (mantle regassing). Current estimates of subduction water fluxes predict that regassing exceeds degassing [...]
Structural controls on the emplacement and evacuation of magma from a sub-volcanic laccolith; Reyðarártindur Laccolith, SE Iceland
Published: 2021-01-06
Subjects: Earth Sciences, Geology, Higher Education, Physical Sciences and Mathematics, Science and Mathematics Education, Tectonics and Structure, Volcanology
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 [...]
2-D P-SV and SH spectral element modelling of seismic wave propagation in non-linear media with pore-pressure effects
Published: 2021-01-06
Subjects: Earth Sciences, Engineering, Geophysics and Seismology, Geotechnical Engineering
It has long been recognized that the effects of superficial geological layers, or site effects, can play a major role on the seismic ground motion at the free surface. In this study, we compute wave propagation in a 2-D asymmetrical basin considering both soil non-linearity and pore- pressure effects. Equations of elastodynamics of wave propagation are solved using the spectral element method [...]
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 [...]
Combination of GNSS orbits using variance component estimation
Published: 2020-12-22
Subjects: Earth Sciences, Other Earth Sciences
Over the past years, the International GNSS Service (IGS) has been putting efforts into extending its service towards the Multi-GNSS Experiment and Pilot Project (MGEX). Several MGEX Analysis Centers (ACs) contribute by providing solutions containing not only GPS and GLONASS but also Galileo, BeiDou, and QZSS. The MGEX orbit and clock combination is a product that is still not consolidated inside [...]
Yield estimation of the 2020 Beirut explosion using open access waveform and remote sensing data
Published: 2020-12-22
Subjects: Applied Statistics, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics, Statistics and Probability
We report on a multi-technique analysis using publicly available data for investigating the huge, accidental explosion that struck the city of Beirut, Lebanon, on August 4, 2020. Its devastating shock wave led to thousands of injured with more than two hundred fatalities and caused immense damage to buildings and infrastructure. Our combined analysis of seismological, hydroacoustic, infrasonic [...]
Small-scale lithospheric heterogeneity characterization using Bayesian inference
Published: 2020-12-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Observations from different disciplines have shown that our planet is highly heterogeneous at multiple scale lengths. Still, many seismological Earth models tend not to include any small-scale heterogeneity or lateral velocity variations, which can affect measurements and predictions based on these homogeneous models. In this study, we describe the lithospheric small-scale heterogeneity structure [...]
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 [...]
Constraining the 410-km Discontinuity and Slab Structure in the Kuril Subduction Zone with Triplication Waveforms
Published: 2020-12-17
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The detailed structure near the 410-km discontinuity provides key constraints of the dynamic interactions between the upper mantle and the lower mantle through the mantle transition zone (MTZ) via mass and heat exchange. Meanwhile, the temperature of the subducting slab, which can be derived from its fast wave speed perturbation, is critical for understanding the mantle dynamics in subduction [...]
Uncertainty Estimation with Deep Learning for Rainfall-Runoff Modelling
Published: 2020-12-17
Subjects: Earth Sciences, Hydrology
Deep Learning is becoming an increasingly important way to produce accurate hydrological predictions across a wide range of spatial and temporal scales. Uncertainty estimations are critical for actionable hydrological forecasting, and while standardized community benchmarks are becoming an increasingly important part of hydrological model development and research, similar tools for benchmarking [...]
Mechanisms for avulsion on alluvial fans: insights from high-frequency topographic data
Published: 2020-12-17
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Avulsion is a key process in building alluvial fans, but it is also a formidable natural hazard. Based on laboratory experiments monitored with novel high-frequency photogrammetry, we present a new model for avulsion on widely graded gravel fans. Previous experimental studies of alluvial fans have suggested that avulsion occurs in a periodic autogenic cycle, that is thought to be mediated by the [...]
Quantitative uncertainty analysis of gravity disturbance. The case of the Geneva Basin (Switzerland)
Published: 2020-12-17
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Gravity data from the International Gravimetric Bureau and the Gravimetric Atlas of Switzerland have been used to evaluate their application and limitations as a subsurface investigation tool to constrain key geological structures in support of the georesources exploration in the Geneva Basin (GB). In this context, the application of an effective processing workflow able to produce a [...]
The influence of orbital parameters on the North American Monsoon system during the Last Interglacial Period
Published: 2020-12-17
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology
The response of summer precipitation in the western U.S. to climate variability remains a subject of uncertainty. For example, paleoclimate records indicate the North American monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modeling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to [...]