Preprints
Filtering by Subject: Earth Sciences
‘Scallywag Bunkers’: Geophysical Investigations of WW2 Auxiliary Unit Operational Bases (OBs) in the UK
Published: 2020-02-05
Subjects: Earth Sciences, Education, Geography, Other Earth Sciences, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Social and Behavioral Sciences
In 1940, with the fall of France imminent, Britain prepared for invasion. After Dunkirk, with most armour and transport lost, a defence ‘stop line’ (GHQ Line) was prepared. Local Defence Volunteers (later Home Guard) were raised to buy time for the Home Army to deploy. Secret ‘Auxiliary Units’ were also formed, tasked with ‘Scallywagging’ – guerrilla activities ––in the invading army’s rear. 4-8 [...]
A new model for fault growth during syn-kinematic deposition
Published: 2020-02-04
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Constraining the mechanisms of fault growth is essential for understanding extensional tectonics. In these dynamic systems the propagation of existing faults through recent syn-kinematic depositions is a poorly understood yet critical process. To understand how underlying structures influence faulting, we examine fault growth in a 10 kyr magmatically-resurfaced region of the Krafla fissure swarm, [...]
Fault rupture during the December 26, 2018, Mw 4.9 Fleri earthquake (Mt. Etna): surface faulting in a volcano-tectonic environment
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
On December 26, 2018, the largest instrumental earthquake ever recorded in Mt. Etna (Sicily, southern Italy) shook the eastern flank of the volcano, with epicenter near the Fleri village along the right-lateral Fiandaca Fault (focal depth less than 1 km, Mw 4.9). The mainshock was accompanied by widespread surface faulting. We surveyed and mapped the coseismic ground ruptures and collected [...]
High-resolution surface velocities and strain for Anatolia from Sentinel-1 InSAR and GNSS data
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Measurements of present-day surface deformation are essential for the assessment of long-term seismic hazard. The European Space Agencys Sentinel-1 satellites enable global, high-resolution observation of crustal motion from Interferometric Synthetic Aperture Radar (InSAR). We have developed new automated InSAR processing systems that exploit the first ~5 years of Sentinel-1 data to measure [...]
Base Level Changes based on Basin Filling Modelling: a Case Study from the Paleocene Lishui Sag, East China Sea Basin
Published: 2020-02-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Estimation of base level changes in geological records is an important topic for petroleum geologists. Taking the Paleocene Upper Lingfeng Member of Lishui Sag as an example, this paper conducted a base level reconstruction based on Basin Filling Modelling (BFM). The reconstruction was processed on the ground of a previously interpreted seismic stratigraphic framework with several assumptions and [...]
Novel insights from Fe-isotopes into the lithological heterogeneity of Ocean Island Basalts and plume-influenced MORBs
Published: 2020-02-02
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Volcanology
The extent of lithological heterogeneity in the Earth’s convecting mantle is highly debated. Whilst the presence of pyroxenite in the mantle source regions of Ocean Island Basalts (OIBs) has traditionally been constrained using the minor-element chemistry of olivine phenocrysts, recent studies have shown that the Ni and Mn contents of primitive olivines are influenced by the conditions of mantle [...]
Entangled external and internal controls on submarine fan evolution: an experimental perspective
Published: 2020-02-02
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Submarine fans are formed by sediment-laden flows shed from continental margins into ocean basins. Their morphology represents the interplay of external controls such as tectonics, climate, and sea-level with internal processes including channel migration and lobe compensation. However, the nature of this interaction is poorly understood. We used physical modelling to represent the evolution of a [...]
Integrating suspended sediment flux in large alluvial river channels: Application of a synoptic Rouse-based model to the Irrawaddy and Salween rivers
Published: 2020-02-02
Subjects: Earth Sciences, Geochemistry, Geology, Geomorphology, Hydrology, Physical Sciences and Mathematics, Sedimentology
A large portion of freshwater and sediment is exported to the ocean by a small number of major rivers. Many of these mega-rivers are subject to substantial anthropogenic pressures, which are having a major impact on water and sediment delivery to deltaic ecosystems. Due to hydrodynamic sorting, sediment grain size and composition varies strongly with depth and across the channel in large rivers, [...]
Fate of organic compounds during transformation of ferrihydrite in iron formations
Published: 2020-01-30
Subjects: Biogeochemistry, Chemistry, Earth Sciences, Physical Chemistry, Physical Sciences and Mathematics
The absence of organic compounds from Precambrian iron formations (IF) challenges the hypothesis of the biogenic origin of IF. Here we address the fate of adsorbed organic compounds during transformation from ferrihydrite to hematite. We determined the binding energy between hematite and common molecular terminations found in extracellular polymeric substances and biofilms: carboxylic, hydroxyl [...]
Monitoring seasonal variations in seismic velocity and groundwater levels in Harvey, Western Australia using borehole ambient seismic noise interferometry
Published: 2020-01-30
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
In order to explore the relationships between environmental subsurface changes and seismic velocities, we use nearly four years (2015-2018) of continuous ambient seismic noise data recorded in a multi-level borehole sensor array to measure relative seismic velocity changes at the SW Hub CO2 Geosequestration Site in Harvey, Western Australia using seismic noise interferometry. We find a direct [...]
Sensitivity Analysis of a Conceptual, Lumped Model Using VARS-TOOL Applied to Western Ghats Catchments of India
Published: 2020-01-30
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Hydrology, Other Civil and Environmental Engineering, Physical Sciences and Mathematics, Water Resource Management
The present work considers the application of Variogram Analysis of Response Surfaces Toolbox (VARS-TOOL) to identify the sensitive parameters of a rainfall-runoff model in the Netravati river basin of Karnataka, India using the global sensitivity analysis method. The statistical bootstrapping method is used to obtain the confidence intervals around each of the sensitivity indices. The VARS-TOOL [...]
Avalonia, get bent! Paleomagnetism from SW Iberia confirms the Greater Cantabrian Orocline
Published: 2020-01-29
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The amalgamation of Pangea formed the contorted Variscan-Alleghanian orogen, suturing Gondwana and Laurussia during the Carboniferous. From all swirls of this orogen, a double curve stands out in Iberia, the coupled Cantabrian Orocline and Central Iberian Curve. The Cantabrian Orocline formed subsequent to Variscan orogeny (ca. 315-295 Ma). The mechanisms of formation for this orocline are [...]
High Attenuation Recycled Materials as landfill liners (the HARM project) – A new concept for improved landfill liner design
Published: 2020-01-28
Subjects: Bioresource and Agricultural Engineering, Civil and Environmental Engineering, Earth Sciences, Education, Engineering, Engineering Science and Materials, Environmental Public Health, Environmental Sciences, Geochemistry, Geotechnical Engineering, Hydrology, Medicine and Health Sciences, Physical Sciences and Mathematics, Public Health, Soil Science
A new approach in landfill liner design which combines hydraulic containment of leachate with contaminant attenuation to improve the performance of these environmental control systems at landfills is described. The idea is to re-use readily available industrial waste residues (construction and biomass waste) as additives for natural clay liners, wherein the additives have specific properties [...]
Event-based contact angle measurements inside porous media using time-resolved micro-computed tomography
Published: 2020-01-28
Subjects: Earth Sciences, Fluid Dynamics, Hydrology, Physical Sciences and Mathematics, Physics
Hypothesis Capillary-dominated multiphase flow in porous materials is strongly affected by the pore walls’ wettability. Recent micro-computed tomography (mCT) studies found unexpectedly wide contact angle distributions measured on static fluid distributions inside the pores. We hypothesize that analysis on time-resolved mCT data of fluid invasion events may be more directly relevant to the fluid [...]
Suspended-sediment induced stratification inferred from concentration and velocity profile measurements in the lower Yellow River, China
Published: 2020-01-27
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Sedimentology
Despite a multitude of models predicting sediment transport dynamics in an open-channel flow, the interaction between fluid and sediment, so to produce self-organized vertical density stratification, has not been robustly investigated and as such is poorly understood. This two-phase phenomenon develops in channels that possess low channel-bed slope and high sediment concentration. As the Yellow [...]