Preprints
There are 5932 Preprints listed.
Bedform segregation and locking increase storage of natural and synthetic particles in rivers
Published: 2021-09-24
Subjects: Engineering
While the ecological significance of hyporheic exchange and fine particle transport in rivers is well established, these processes are generally considered irrelevant to riverbed morphodynamics. We show that coupling between hyporheic exchange, suspended sediment deposition, and sand bedform motion strongly modulates morphodynamics and sorts bed sediments. Hyporheic exchange focuses fine-particle [...]
Deep Deconvolution for Traffic Analysis with Distributed Acoustic Sensing Data
Published: 2021-09-23
Subjects: Artificial Intelligence and Robotics, Geophysics and Seismology, Transportation Engineering
Distributed Acoustic Sensing (DAS) is a novel vibration sensing technology that can be employed to detect vehicles and to analyse traffic flows using existing telecommunication cables. DAS therefore has great potential in future "smart city" developments, such as real-time traffic incident detection. Though previous studies have considered vehicle detection under relatively light traffic [...]
Imaging an Underwater Basin and its Resonance Modes using Optical Fiber Distributed Acoustic Sensing
Published: 2021-09-23
Subjects: Earth Sciences, Geophysics and Seismology
Distributed acoustic sensing is an ideal tool for ambient noise tomography owing to the dense spatial measurements and the ability to continuously record in harsh environments, such as underwater. We demonstrate the ability to image a complex underwater basin using ambient noise recorded on a fiber deployed offshore Greece. A two-dimensional shear-wave velocity model was derived by analyzing [...]
Dam Break Simulation with HEC-RAS and OpenFOAM
Published: 2021-09-23
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
A dam break is a natural disaster that can cause significant property damage and loss of life. It's useful to identify potential flooding areas downstream in the event of a dam break. In this study both HEC-RAS and OpenFOAM are set up to simulate the inundation map downstream of the Dworshak dam in Idaho. Using the same topographical data from satellite observations, similar computational [...]
Stalagmite evidence for Early Holocene multidecadal hydroclimate variability in Ethiopia
Published: 2021-09-22
Subjects: Geochemistry, Geology, Speleology
A multiproxy oxygen and carbon isotope (d13C and d18O), growth rate and trace element stalagmite paleoenvironmental record is presented for the Early Holocene from Achere Cave, Ethiopia. The annually laminated stalagmite grew from 10.6 to 10.4 ka, and from 9.7 to 9.0 ka with a short hiatus at ~9.25 ka. Using oxygen and carbon isotopic, and cave monitoring data, we demonstrate that the stalagmite [...]
Missing or Underrated Super-emitters of Nitrogen Oxides in China Exposed from Space
Published: 2021-09-21
Subjects: Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
Nitrogen oxides (NOx ≡ NO + NO2) play a central role in air pollution. Super-emitters present unique opportunities for emission mitigation in China and beyond. They comprise intensive industrial facilities (e.g., power or chemical plants), less than 1 × 1 km2 with high NOx plumes, dominating localized concentrations within a limited geographical scope. However, identification of super-emitters [...]
The evolution of triple junctions: from failure to success
Published: 2021-09-20
Subjects: Physical Sciences and Mathematics
Divergent triple junctions are stable plate margins where three spreading ridges meet. Although it is accepted that this configuration is inherited from an earlier phase of continental rifting, how post-breakup triple junctions emerge from the separation of two plates remains unclear. By documenting the strain rate history recorded in the three rift-arms of several modern and ancient triple [...]
The formation and evolution of submarine headless channels
Published: 2021-09-18
Subjects: Physical Sciences and Mathematics
The scale of submarine channels can rival or exceed those formed on land and they form many of the largest sedimentary deposits on Earth. Turbidity currents that carve submarine channels pose a major hazard to offshore cables and pipelines, and transport globally significant amounts of organic carbon. Alongside the primary channels, many systems also exhibit a range of headless channels, which [...]
Hydroclimatic adaptation critical to the resilience of tropical forests
Published: 2021-09-18
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Forest Biology, Hydrology, Remote Sensing
Forest and savanna ecosystems naturally exist as alternative stable states. The maximum capacity of these ecosystems to absorb perturbations without transitioning to the other alternative stable state is referred to as ‘resilience’. Previous studies have determined the resilience of terrestrial ecosystems to hydroclimatic changes predominantly based on space-for-time substitution. This [...]
Shear-wave Anisotropy in the Earth’s Inner Core
Published: 2021-09-18
Subjects: Earth Sciences, Geophysics and Seismology, Mineral Physics, Physical Sciences and Mathematics
Earth’s inner core anisotropy is widely used to infer the deep Earth's evolution and present dynamics. Many compressional-wave anisotropy models have been proposed based on seismological observations. In contrast, inner-core shear-wave (J-wave) anisotropy – on a par with the compressional-wave anisotropy – has been elusive. Here we present a new class of the J-wave anisotropy observations [...]
Changes in deep groundwater flow patterns related to oil and gas
Published: 2021-09-18
Subjects: Engineering, Physical Sciences and Mathematics
Large volumes of saline formation water are both produced from and injected into sedimentary basins as a by-product of oil and gas production. Despite this, the location of production and injection wells has not been studied in detail at the regional scale and the effects on deep groundwater flow patterns (i.e. below the base of groundwater protection) possibly driving fluid flow towards shallow [...]
Upper Plate Structure and Tsunamigenic Faults near the Kodiak Islands, Alaska
Published: 2021-09-18
Subjects: Physical Sciences and Mathematics
The Kodiak Islands lie near the southern terminus of the 1964 Great Alaska earthquake rupture area and within the Kodiak subduction zone segment. Both local and trans-Pacific tsunamis were generated during this devastating megathrust event, but the local tsunami source region and the causative faults are poorly understood. We provide an updated view of the tsunami and earthquake hazard for the [...]
Analogue modelling of the interplay between gravity gliding and spreading across complex rift topography in the Santos Basin
Published: 2021-09-17
Subjects: Geology, Tectonics and Structure
The Santos Basin presents a complex and controversial evolution and distribution of salt tectonics domains. The controversies revolve mainly around the kinematically- linked Albian Gap and São Paulo Plateau. The Albian Gap is a ~450 km long and 60 km wide feature characterized by a post-Albian counter-regional rollover overlying depleted Aptian salt and in which the Albian is absent. The São [...]
Selling the Earth: re-purposing geoscience communications
Published: 2021-09-17
Subjects: Education, Physical Sciences and Mathematics
Earth scientists have a critical role to play in communicating to the public and policy makers what we know about looming societal threats including climate change, extreme natural events, resource conflicts and the energy transition. But whilst geoscientists are being encouraged - and, increasingly, trained - to ‘go public’ with our science, what is less clear is to what extent our current [...]
The Impact of Neglecting Climate Change and Variability on ERCOT’s Forecasts of Electricity Demand in Texas
Published: 2021-09-16
Subjects: Earth Sciences, Environmental Sciences, Environmental Studies, Oceanography and Atmospheric Sciences and Meteorology, Risk Analysis
The Electric Reliability Council of Texas (ERCOT) manages the electric power across most of Texas. They make short-term assessments of electricity demand based on historical weather over the last decade or two, thereby ignoring the effects of climate change and the possibility of weather variability outside of the recent historical range. In this paper, we develop an empirical methodology to [...]