Preprints
Filtering by Subject: Geophysics and Seismology
Broadband Ocean Bottom Seismometer Noise Properties
Published: 2022-05-13
Subjects: Geophysics and Seismology
We present a new compilation and analysis of broadband ocean bottom seismometer noise properties from 15 years of seismic deployments. We compile a comprehensive dataset of representative four-component (seismometer and pressure gauge) noise spectra and cross-spectral properties (coherence, phase, and admittance) for 551 unique stations spanning 18 US-led experiments. This is matched with a [...]
Rheology of debris-flow materials is controlled by the distance from jamming
Published: 2022-05-13
Subjects: Geophysics and Seismology
Debris flows are dense and fast-moving complex suspensions of soil and water that threaten lives and infrastructure. Assessing the hazard potential of debris flows requires predicting yield and flow behavior. Reported measurements of rheology for debris-flow slurries are highly variable and sometimes contradictory, due to heterogeneity in grain size, shape, chemical composition, and solid-volume [...]
The signature of lithospheric anisotropy at post-subduction continental margins: new insight from XKS splitting analysis in northern Borneo
Published: 2022-05-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
The relative paucity of recent post-subduction environments globally has meant that, so far, little is known about tectonic processes that occur during and after subduction termination, as previously convergent tectonic plates adjust to the new stress regime. The region of Southeast Asia that now encompasses northern Borneo has been host to two sequential episodes of subduction—both now [...]
Tidal Turbine Array Modelling using Goal-Oriented Mesh Adaptation
Published: 2022-04-30
Subjects: Civil and Environmental Engineering, Fluid Dynamics, Geophysics and Seismology, Numerical Analysis and Computation, Partial Differential Equations
Purpose: To examine the accuracy and sensitivity of tidal array performance assessment by numerical techniques applying goal-oriented mesh adaptation. Methods: The goal-oriented framework is designed to give rise to adaptive meshes upon which a given diagnostic quantity of interest (QoI) can be accurately captured, whilst maintaining a low overall computational cost. We seek to improve the [...]
Uncertainty quantification of multi-modal surface wave inversion using artificial neural networks
Published: 2022-04-29
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
An inversion of surface waves dispersion curves is a non-unique and ill-conditioned problem. The inversion result has a probabilistic nature, which becomes apparent when simultaneously restoring the shear wave (S-wave) velocity and layer thickness. Therefore, the problem of uncertainty quantification is relevant. Existing methods through deterministic or global optimization approaches of [...]
Machine learning and marsquakes: a tool to predict atmospheric-seismic noise for the NASA InSight mission
Published: 2022-04-27
Subjects: Geophysics and Seismology, Planetary Geophysics and Seismology
The SEIS experiment on the NASA InSight mission has catalogued hundreds of marsquakes so far. However, the detectability of these events is controlled by the weather which generates seismic noise. This affects the catalogue on both diurnal and seasonal scales. We propose to use machine learning methods to fit the wind, pressure and temperature data to the seismic energy recorded in the 0.4-1 Hz [...]
Range Geolocation Accuracy of C-/L-Band SAR and Its Implications for Operational Stack Coregistration
Published: 2022-04-22
Subjects: Geophysics and Seismology, Signal Processing
Time series analysis of synthetic aperture radar (SAR) and interferometric SAR generally starts with coregistration for the precise alignment of the stack of images. Here we introduce a model-adjusted geometrical image coregistration (MAGIC) algorithm for stack coregistration. This algorithm corrects for atmospheric propagation delays and known surface motions using existing models and ensures [...]
Coastal River Response to Transgression: A New Look at the Trinity Incised Valley Using Multi-Resolution Seismic Imaging
Published: 2022-03-29
Subjects: Earth Sciences, Geology, Geomorphology, Geophysics and Seismology, Sedimentology
Modern lowland river systems show transitions in flow characteristics near coastlines that lead to systematic changes in sediment deposition and stratigraphic architecture. Sensitivity of fluvial morphodynamics to base-level has important implications for the prediction and interpretation of fluvial stratigraphy, particularly in deposits formed during periods of relative sea-level rise such as [...]
CCC - integrated multiscale study of salt cavern abandonment in the Netherlands
Published: 2022-03-24
Subjects: Geology, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Mining Engineering, Other Earth Sciences, Tectonics and Structure
The KEM-17 project of the Dutch State Supervision of Mines presented a critical review of concepts of cavern abandonment and related science. It recommended that analyses of cavern abandonment are done as an integrated project, addressing (i) micro-scale physical processes, (ii) cavern scale models based on field scale experiments and numerical models, (iii) the salt dome scale, to model the far [...]
Reducing the Uncertainty of Multi-Well Petrophysical Interpretation from Well Logs via Machine-Learning and Statistical Models
Published: 2022-03-23
Subjects: Analysis, Earth Sciences, Engineering, Geophysics and Seismology, Mining Engineering, Multivariate Analysis, Statistical Methodology, Statistical Models
Well-log interpretation provides in situ estimates of formation properties such as porosity, hydrocarbon pore volume, and permeability. Reservoir models based on well-log-derived formation properties deliver reserve-volume estimates, production forecasts, and help with decision making in reservoir development. However, due to measurement errors, variability of well logs due to multiple [...]
Internal Planetary Feedbacks, Mantle Dynamics, and Plate Tectonics
Published: 2022-03-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Sciences, Tectonics and Structure
Isolating planetary feedbacks, and feedback analysis, are prevalent aspects of climate and Earth surface process science. An under appreciation of internal planet feedbacks, and feedback analysis for plate tectonics research, motivate this chapter. We review feedbacks that influence the Earth's thermal evolution and expand them to include magmatic history and planetary water budgets. The [...]
Geodynamics of continental rift initiation and evolution
Published: 2022-03-07
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
A rift is a nascent plate boundary where continental lithosphere is extended and possibly broken. In the geologic past, rifting played a major role in shaping the surface of our planet, while at present, continental rifts are of societal relevance by hosting key georesources such as geothermal energy and ore deposits. This Review discusses fundamental rift processes, geodynamic forces and their [...]
Magma chamber detected beneath an arc volcano with high-resolution velocity images
Published: 2022-03-05
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Volcanology
Arc volcanoes are underlain by complex systems of molten-rock reservoirs ranging from melt-poor mush zones to melt-rich magma chambers. Petrological and satellite data indicate that eruptible magma chambers form in the topmost few kilometres of the crust. However, very few chambers have ever been definitively located, suggesting that most are too short-lived or too small to be imaged, which has [...]
Heralds of a Future Eruption? Swarms of Microseismicity beneath the submarine Kolumbo Volcano indicate Opening of near-vertical Fractures exploited by ascending Melts
Published: 2022-02-28
Subjects: Geophysics and Seismology
The Kolumbo submarine volcano in the southern Aegean (Greece) is associated with repeated seismic unrest since at least two decades and the causes of this unrest are still hardly understood. We present a ten-month long microseismicity dataset for the period 2006-2007. The majority of earthquakes clusters in a cone-shaped portion of the crust below Kolumbo. The tip of this cone coincides with a [...]
Along-Dip Segmentation of the Slip Behavior and Rheology of the Copiapó Ridge Subducted in North-Central Chile
Published: 2022-02-24
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
We studied the along-dip influence of the Copiapó ridge subduction in the Atacama region, North-Central Chile by building a new seismicity catalog, including similar events and non-volcanic tremors (NVTs). We also obtained a 3-D tomographic model for P- and S-waves velocity (and the implied Vp/Vs ratio). We identify down-dip segmentation involving 4 distinct segments: a locked seismogenic zone [...]