Preprints
Filtering by Subject: Physical Sciences and Mathematics
Isotropic and Azimuthally Anisotropic Rayleigh Wave Dispersion Across the Juan de Fuca and Gorda Plates and U.S. Cascadia from Earthquake Data and Ambient Noise Two- and Three-Station Interferometry
Published: 2020-08-08
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Physics
We use data from the Cascadia Initiative (CI) amphibious array and the USArray Transportable Array to construct and compare Rayleigh wave isotropic and azimuthally anisotropic phase speed maps across the Juan de Fuca and Gorda Plates extending onto the continental north- western United States. Results from both earthquakes (28–80 s) as well as ambient noise two- and three-station interferometry [...]
GeospatialVR: A Web-based Virtual Reality Framework for Collaborative Environmental Simulations
Published: 2020-08-08
Subjects: Civil and Environmental Engineering, Computer Sciences, Databases and Information Systems, Engineering, Environmental Engineering, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Graphics and Human Computer Interfaces, Physical Sciences and Mathematics
This research introduces GeospatialVR, an open-source collaborative virtual reality framework to dynamically create 3D real-world environments that can be served on any web platform and accessed via desktop and mobile devices and virtual reality headsets. The framework can generate realistic simulations of desired locations entailing the terrain, elevation model, infrastructures, dynamic [...]
Taking the pulse of salt-detached gravity gliding in the eastern Mediterranean
Published: 2020-08-05
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
We investigate early-stage salt-detached gliding using a 3D seismic dataset from the Levant Margin in the Eastern Mediterranean, where gravitational instability due to margin uplift has caused north-westward translation of the Messinian salt sheet and its Plio-Pleistocene clastic overburden. Large, NE-trending, base-salt anticlines have allowed the basinward translation to be recorded by the [...]
Hydrogeologic and Geochemical Distinctions in Salar Freshwater Brine Systems
Published: 2020-08-05
Subjects: Earth Sciences, Geochemistry, Hydrology, Physical Sciences and Mathematics
The Salar de Atacama contains one of the world’s most important lithium resources and hosts unique and fragile desert ecosystems. Water use issues of the hyper-arid region have placed it at the center of global attention. This investigation is the first robust assessment of a salar system to incorporate geology, hydrogeology, and geochemistry of the aquifer system in the inflow, transition zone [...]
Leaky salt: pipe trails record the history of cross-evaporite fluid escape in the northern Levant Basin, Eastern Mediterranean
Published: 2020-08-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Despite salt being regarded as an extremely efficient, low-permeability hydraulic seal, an increasing number of cross-evaporite fluid escape features have been documented in salt-bearing sedimentary basins. Because of this, it is clear that our understanding of how thick salt deposits impact fluid flow in sedimentary basins is incomplete. We here examine the causes and evolution of [...]
Principal component analysis of seismic facies
Published: 2020-08-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Seismic facies analyses are fundamental to the study of sedimentary, tectonic and magmatic systems using seismic reflection data. These analyses generally assume that seismic facies are: (1) well defined, (2) distinct and (3) prevalent patterns in the data. Here, we examine these assumptions critically. First, we demonstrate how to extract the main seismic facies from conventional industry [...]
Paucity of legacy oil and gas subsurface data onshore United Kingdom: implications for the expansion of low carbon subsurface activities and technologies
Published: 2020-08-04
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
The decarbonisation of energy systems to achieve net zero carbon emissions will likely see the rapid development of carbon capture and storage, energy storage in the subsurface and geothermal energy projects. Subsurface data such as seismic reflection surveys and borehole data are vital for geoscientists and engineers to carry out comprehensive assessments of both the opportunities and risks for [...]
Seismic diffraction imaging to better characterise mass-transport complexes: examples from the Gulf of Cadiz, south west Iberian Margin
Published: 2020-08-03
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Mass‐transport complexes (MTCs) are often characterised by small‐scale, discontinuous internal structure, such as slide blocks, rough interfaces, faults and truncated strata. Seismic images may not properly resolve such structure because seismic reflections are fundamentally limited in lateral resolution by the source bandwidth. The relatively weak seismic diffractions, instead, encode [...]
Serious Gaming for Water Resources Planning and Hazard Mitigation
Published: 2020-08-03
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Education, Environmental Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Hydrological hazards lead to a broad range of socio-economic and environmental risks. The development of a resilient community and risk reduction heavily rely on the adoption of holistic watershed master planning whereby the adaptation options consider the risk associated with individual or multiple hydrological hazards occurring simultaneously at a specific location. Such planning approaches [...]
An imbalancing act: the dynamic response of the Kaskawulsh Glacier to a changing mass budget
Published: 2020-08-03
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
The Kaskawulsh Glacier is an iconic outlet draining the icefields of the St. Elias Mountains in Yukon, Canada. We determine and attempt to interpret its catchment-wide mass budget since 2007. Using SPOT5/6/7 data we estimate a 2007-2018 geodetic balance of $-$0.46 $\pm$ 0.17 m w.e. a$^{-1}$. By comparing computed balance fluxes with observed ice fluxes at nine flux gates we examine the [...]
Notes on Seismic Source Models in Elastostatics
Published: 2020-07-31
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Seismic source models in elastostatics lay the foundations for the popular earthquake deformation formula derived in Okada (1992), which forms key components for many studies in earthquake displacement simulations, earthquake source inversions and ground-motion predictions. However,despite of their importance, we found that the assumptions and proofs of some important theorems about the topic are [...]
Inferring Interseismic Coupling along the Lesser Antilles Arc: a Bayesian Approach
Published: 2020-07-31
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The Lesser Antilles subduction zone is a challenging region when it comes to unraveling its seismogenic behavior. Over the last century, the subduction megathrust has been seismically quiet, with no large thrust event recorded, which raises the question whether this subduction zone is able to produce large interplate earthquakes or not. However, two historical earthquakes in the 19th century, a M [...]
The formation and implications of giant blocks and fluid escape structures in submarine lateral spreads
Published: 2020-07-30
Subjects: Earth Sciences, Geology, Medicine and Health Sciences, Physical Sciences and Mathematics, Sedimentology
Lateral spread (or ‘spreading’) and submarine creep are processes that occur near the headwalls of both terrestrial landslides and submarine mass-transport complexes (MTCs). Both submarine creep and spread deposits may contain giant (km-scale) coherent blocks, but their transport processes remain poorly constrained. Here we use 2D and 3D seismic reflection data to determine the geometry, scale, [...]
Robust Q estimation using surface seismic data
Published: 2020-07-30
Subjects: Applied Mathematics, Computational Engineering, Earth Sciences, Engineering, Geophysics and Seismology, Numerical Analysis and Computation, Physical Sciences and Mathematics
Direct wave arrivals are the most robust signals to determine velocity and consequently they have been used for almost a century in hydrocarbon exploration. The reason is simple as the arrivaltime is explicitly available and provide a direct measurement of the average velocity of the sub-surface ray-path. These signals have not been extensively used to estimate attenuation or Q. One reason may [...]
Basement-Controlled Deformation of Sedimentary Sequences, Anadarko Shelf, Oklahoma
Published: 2020-07-30
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Structures rooted in the crystalline basement frequently control the deformation of the host bedrock and the overlying sedimentary sequences. Here, we elucidate the structure of the c. 2‐km deep Precambrian granitic basement in the Anadarko Shelf, Oklahoma, and how the propagation of basement faults deformed the sedimentary cover. Although the basin is foreland in origin, the gently dipping shelf [...]