Preprints
Filtering by Subject: Physical Sciences and Mathematics
The Effect of Formation Processes on The Frequency of Palaeolithic Cave Sites in Semi-Arid Zones: Insights From Kazakhstan
Published: 2021-10-01
Subjects: Earth Sciences, Geomorphology, Other Environmental Sciences, Physical Sciences and Mathematics, Sedimentology, Social and Behavioral Sciences, Speleology, Stratigraphy
Central Asian caves with Palaeolithic deposits are few but they provide a rich record of human fossils and cultural assemblages that has been used to model Late Pleistocene hominin dispersals. However, previous research has not yet systematically evaluated the formation processes that influence the frequency of Palaeolithic cave sites in the region. To address this deficiency, we combined field [...]
Spacing and Strain During Multiphase Boudinage in 3D
Published: 2021-10-01
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Most models of brittle boudinage predict a dependency of fracture spacing on thickness of the boudinaged layer. This basic relationship can be distorted in the case of multiphase boudinage, where structural inheritance, possibly combined with time evolution of rheology affects boudin geometries, but is not recognized in 2D outcrops. Here we present analyses from a metre-scale, serially sectioned [...]
Mapping riverbed sediment size from Sentinel 2 satellite data
Published: 2021-10-01
Subjects: Physical Sciences and Mathematics
A comprehensive understanding of river dynamics requires quantitative knowledge of the grain size distribution of bed sediments and its variation across different temporal and spatial scales. Several techniques are already available for grain size assessment based on field and remotely sensed data. However, the existing methods are only applicable on small spatial scales and on short time scales. [...]
Tracking Barrier Island Response to Early Holocene Sea-level Rise: High Resolution Study of Estuarine Sediments in the Trinity River Paleovalley
Published: 2021-10-01
Subjects: Physical Sciences and Mathematics
Understanding how barrier islands respond to factors such as variations in sediment supply, relative sea-level rise, and accommodation is valuable for preparing coastal communities for future impacts of climate change. Increasingly, the underlying antecedent topography has been observed to have a significant control on the evolution of the barrier island system by providing increased elevation, [...]
Early Pliocene Marine Transgression into the Lower Colorado River Valley, Southwestern USA, by Re-Flooding of a Former Tidal Strait
Published: 2021-09-29
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
Marine straits and seaways are known to host a wide range of sedimentary processes and products, but the role of marine connections in the development of large river systems remains little studied. This study explores a hypothesis that shallow marine waters flooded the lower Colorado River valley at ~ 5 Ma along a fault-controlled former tidal straight, soon after the river was first integrated [...]
Deterministic model of the eddy dynamics for a midlatitude ocean model
Published: 2021-09-29
Subjects: Physical Sciences and Mathematics
Mesoscale eddies, the weather system of the oceans, although being on the scales of O(20-100 km), have a disproportionate role in shaping the mean stratification, which varies on the scale of O(1000 km). With the increase in computational power, we are now able to partially resolve the eddies in basin-scale and global ocean simulations, a model resolution often referred to as mesoscale [...]
An anisotropic equation of state for high pressure, high temperature applications
Published: 2021-09-25
Subjects: Condensed Matter Physics, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Mineral Physics
This paper presents a strategy for consistently extending isotropic equations of state to model anisotropic materials over a wide range of pressures and temperatures under nearly hydrostatic conditions. The method can be applied to materials of arbitrary symmetry. The paper provides expressions for the deformation gradient tensor, the lattice parameters, the isothermal elastic compliance tensor [...]
A survey of storm-induced seaward-transport features observed during the 2019 and 2020 hurricane seasons
Published: 2021-09-24
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Hurricanes are known to play a critical role in reshaping coastlines, particularly on the open ocean coast in cases of overwash, but storm induced seaward-directed flow and responses are often ignored or un-documented. Subaerial evidence for seaward sediment transport (outwash, return-flow) increases our understanding of the impact hurricanes have on coastal and barrier island evolution. Towards [...]
Dam Break Simulation with HEC-RAS and OpenFOAM
Published: 2021-09-22
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 [...]
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: 2021-09-17
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 [...]
Shear-wave Anisotropy in the Earth’s Inner Core
Published: 2021-09-17
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: 2021-09-17
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: 2021-09-17
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 [...]