Preprints
There are 7090 Preprints listed.
Distributed chaos of the atmospheric tracers
Published: 2021-05-13
Subjects: Physical Sciences and Mathematics
It is shown, using results of numerical simulations, atmospheric experiments and observations with natural trace-gases (ozone, carbon dioxide etc.), that the spatio-temporal distributed chaos can provide good quantitative description of the statistical properties of the passive scalar tracers in the atmosphere from the atmospheric surface layer up to the stratosphere. Related properties of the [...]
Distributed Acoustic Sensing for Near Surface Imaging from Submarine Telecommunication Cable: Case Study in the Trondheim Fjord
Published: 2021-05-13
Subjects: Geophysics and Seismology, Geotechnical Engineering, Signal Processing, Systems and Communications
Distributed acoustic sensing (DAS) transforms submarine telecommunication cables into densely sampled seismic receivers. To demonstrate DAS applications for seismic imaging, we use an optical cable on the seafloor in the Trondheim Fjord, Norway, to record seismic data generated by a controlled seismic source. The data are simultaneously recorded by a towed hydrophone array and the fiber optic [...]
Field evidence for disequilibrium dynamics in preserved fluvial cross-strata: A record of discharge variability or morphodynamic hierarchy?
Published: 2021-05-13
Subjects: Earth Sciences
Bedforms preserved in the rock record can provide detailed information on the morphologies and hydrodynamics of ancient fluvial systems on Earth and other planets. Existing process–product relations for bedform preservation assume that fluvial cross strata reflect conditions under which bedforms were equilibrated with the prevailing flow, i.e., steady-state conditions. However, recent theoretical [...]
A damage model for the frictional shear failure of brittle materials in compression
Published: 2021-05-13
Subjects: Applied Mathematics, Computational Engineering, Earth Sciences, Engineering, Geology, Materials Science and Engineering, Physical Sciences and Mathematics
Damage models have been successfully employed for many decades in the modelling of tensile failure, where the crack surfaces separate as a crack grows. The advantage of this approach is that crack trajectories can be computed simply and efficiently on a fixed finite element mesh without explicit tracking. The development of damage models for shear failure in compression, where the crack faces [...]
AMS and rock magnetism in the Caviahue-Copahue Volcanic Complex (Southern Andes): emission center, flow dynamics, and implications to the emplacement of non-welded PDCs
Published: 2021-05-14
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
Pyroclastic deposits can cover significant areas and register major geological events. Despite their importance, understanding depositional dynamics of pyroclastic density currents (PDCs) and linking explosive deposits to their emission centers is still a challenge, especially in the case of non-welded, massive ignimbrites. Located in the Southern Andes, the Caviahue Copahue Volcanic Complex [...]
Determination of the spatial distribution of wetting in the pore networks of rocks
Published: 2021-05-17
Subjects: Engineering, Physical Sciences and Mathematics
The macroscopic movement of subsurface fluids involved in CO2 storage, groundwater, and petroleum engineering applications is controlled by interfacial forces in the pores of rocks, micrometre to millimetre in length scale. Recent advances in physics based models of these systems has arisen from approaches simulating flow through a digital representation of the complex pore structure. However, [...]
Evaluating the benefits of alternative leak detection programs
Published: 2021-05-15
Subjects: Oil, Gas, and Energy
New technologies have the potential to reduce the cost of leak detection and repair (LDAR) for producers of all sizes through smart LDAR program design, the right combination of technologies, and by collaboration between producers within the same geographic area. This potential was examined in an extensive study by conducting multiple simulations using the Arolytics AROfemp model to evaluate the [...]
Nature and timing of anatectic event of the Hida Belt (Japan): Constraints from titanite geochemistry and U-Pb age of clinopyroxene-bearing leucogranite
Published: 2021-05-17
Subjects: Geochemistry, Geology
The Hida Belt, central Japan, is a continental fragment, which was once a part of the crustal basement of the East Asian continental margin. It consists mainly of Permo-Triassic granite-gneiss complexes with both syn-to-late-metamorphic migmatite or granite bodies. Clinopyroxene-bearing leucogranite, locally called as 'Inishi'-type migmatite, occurs characteristically in the migmatite zone [...]
Chromium evidence for protracted oxygenation during the Paleoproterozoic
Published: 2021-05-18
Subjects: Earth Sciences, Geochemistry, Paleobiology
It has commonly been proposed that the development of complex life—e.g., aerobic eukaryotes—coincided with atmospheric oxygenation. To test this hypothesis, we measured chromium-based oxygen proxies in a >2400-m core from the Onega Basin (NW-Russia), deposited ~2.1–2.0 billion years ago—closely preceding the first eukaryote fossils. Fractionated chromium isotopes are documented throughout the [...]
An initial assessment of community representation and diversity within UK geophysics
Published: 2021-05-17
Subjects: Education
The British Geophysical Association (BGA) is a Joint Association of the Geological Society of London (GSL) and the Royal Astronomical Society (RAS) that aims to promote the subject of geophysics, and to strengthen the relationship between geology and geophysics in the UK. As such, engagement with all members of the geophysics community is integral to our purpose, and we recognise that the Earth [...]
Thermal Modelling Of Post-Fire Permafrost Change Under A Warming Coastal Subarctic Climate, Eastern Canada
Published: 2021-05-18
Subjects: Earth Sciences, Physical Sciences and Mathematics
Forest fires are known to have lasting thermal impacts on permafrost, but there are no previous studies of such effects along the eastern Canadian coastline. One-dimensional thermal modelling was used to examine the ground thermal regime at a coastal forest fire site in the discontinuous permafrost zone near Nain (56.5°N), Nunatsiavut, eastern Canada. Simulations were undertaken for both the [...]
Generation of Earth’s Early Continents From a Relatively Cool Archean Mantle
Published: 2021-06-18
Subjects: Physical Sciences and Mathematics
Several lines of evidence suggest that the Archean (4.0–2.5 Ga) mantle was hotter than today’s potential temperature (TP ) of 1350 ýC. However, the magnitude of such di erence is poorly constrained, with TP estimation spanning from 1500 ýC to 1600 ýC during the Meso-Archean (3.2-2.8 Ga). Such di erences have major implications for the interpreted mechanisms of continental crust generation on [...]
Contributions to Polar Amplification in CMIP5 and CMIP6 Models
Published: 2021-05-18
Subjects: Physical Sciences and Mathematics
As a step towards understanding the fundamental drivers of polar climate change, we evaluate contributions to polar warming and its seasonal and hemispheric asymmetries in Coupled Model Intercomparison Project phase 6 (CMIP6) as compared with CMIP5. CMIP6 models broadly capture the observed pattern of surface- and winter-dominated Arctic warming that has outpaced both tropical and Antarctic [...]
Evaluating the Economic Fairways for Hydrogen Production in Australia
Published: 2021-05-20
Subjects: Chemical Engineering, Natural Resource Economics, Natural Resources Management and Policy, Physical and Environmental Geography, Power and Energy, Water Resource Management
Assessments of hydrogen project viability typically focus on evaluating specific sites for development, or providing generic cost-estimates that are independent of location. In reality, the success of hydrogen projects will be intimately linked to the availability of local energy resources, access to key infrastructure and water supplies, and the distance to export ports and energy markets. In [...]
Integrating ecosystem services information into water resource management: an indicator-based approach
Published: 2021-05-19
Subjects: Environmental Indicators and Impact Assessment, Water Resource Management
Natural ecosystems are fundamental to local water cycles and the water-related ecosystem services that humans enjoy, such as water provision and protection from natural hazards. However, integrating ecosystem services into water resources management requires that they be acknowledged, quantified, and communicated to decision makers. We present an indicator framework that incorporates the supply [...]