Preprints
There are 4725 Preprints listed.
Rainsplash Erosion for Natural Slopes and Rainfall Conditions
Published: 2020-01-24
Subjects: Earth Sciences, Environmental Sciences, Geomorphology, Physical Sciences and Mathematics
Rainsplash is significant for interrill erosion since it facilitates the movement of loosened soil frangments. Because it is a technically dicult process to measure, many studies focus on experimental simulation under controlled conditions both in field and laboratory. Raindrop erosion studies have produced models to predict the erosivity due to raindrop impact on varying ground surfaces, with a [...]
Dynamics of displacement in mixed-wet porous media
Published: 2020-01-22
Subjects: Earth Sciences, Engineering, Fluid Dynamics, Physical Sciences and Mathematics, Physics
We identify a distinct two-phase flow invasion pattern in a mixed-wet porous medium. Time-resolved high-resolution synchrotron X--ray imaging is used to study the invasion of water through a small rock sample filled with oil, characterized by a wide non-uniform distribution of local contact angles both above and below $90^{\circ}$. The water advances in a connected front, but throats are not [...]
Dilation of subglacial sediment governs incipient surge motion in glaciers with deformable beds
Published: 2020-01-22
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Glacier surges are quasi-periodic episodes of rapid ice flow that arise from increases in slip-rate at the ice-bed interface. The mechanisms that trigger and sustain surges are not well-understood. Here, we develop a new model of incipient surge motion for glaciers underlain by sediments to explore how surges may arise from slip instabilities within a thin layer of saturated, deforming subglacial [...]
Pleistocene - Holocene volcanism at the Karkar geothermal prospect, Armenia
Published: 2020-01-22
Subjects: Earth Sciences, Geochemistry, Geology, Other Earth Sciences, Physical Sciences and Mathematics, Volcanology
Quaternary volcanic centres north of the Bitlis-Zagros suture in Turkey, Iran and the Caucasus represent both volcanic hazards and potential or actual geothermal energy resources. Such challenges and opportunities cannot be fully quantified without understanding these volcanoes’ petrogenesis, geochronology and magmatic, tectonic or other eruption triggers. In this preliminary study, we discuss [...]
Spatially distributed chaos and turbulence in clouds
Published: 2020-01-22
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Spatially distributed chaos (turbulence) in the cumulus, stratocumulus, stratiform, cirrus and cirrus mammatus clouds have been studied using results of direct numerical simulations and measurements in the cloudy atmosphere. It is shown that in the considered cases the second order moment of helicity distribution (the Levich-Tsinober invariant) dominates the kinetic energy spectra.
serac: a R package for ShortlivEd RAdionuclide Chronology of recent sediment cores
Published: 2020-01-18
Subjects: Life Sciences, Other Life Sciences
Short-lived radionuclides are measured in surface sediment to provide a geochronology for the past century. Age-depth models can be produced from 210Pbex activity-derived sedimentation rates and confirmed by 137Cs and 241Am activities that are result of fallout from nuclear weapon tests and the Chernobyl accident. Different methods of age depth modelling using such data require expertise in lake [...]
Seismic source tracking with six degree-of-freedom ground motion observations
Published: 2020-01-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Back azimuth (BAz) information can be determined from combined measurements of rotations and translations at a single site. Such six degree-of-freedom (6-DoF) measurements are reasonably stable in delivering similar information compared to a small-scale array of three-component seismometers. Here we investigate whether a 6-DoF approach is applicable to tracking seismic sources. While common [...]
The architecture of an intrusion in magmatic mush
Published: 2020-01-17
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Magmatic reservoirs located in the upper crust have been shown to result from the repeated intrusions of new magmas, and spend much of the time as a crystal-rich mush. The geometry of the intrusion of new magmas may greatly affect the thermal and compositional evolution of the reservoir. Despite advances in our understanding of the physical processes that may occur in a magmatic reservoir, the [...]
A Multivariate Outlier Detection Approach for Water Footprint Assessments in Shale Formations: Case Eagle Ford Play (Texas)
Published: 2020-01-17
Subjects: Civil and Environmental Engineering, Engineering, Environmental Engineering
The increasing trend on water use for hydraulic fracturing (HF) in multiple plays across the U.S. has raised the need to improve the HF water management model. Such approaches require good quality datasets, particularly in water stressed regions. In this work, we presented a QA/QC framework for HF data using a multivariate outlier detection methodology based on five univariate techniques: two [...]
Enhanced iceberg discharge in the western North Atlantic during all Heinrich events of the last glaciation
Published: 2020-01-13
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
A series of catastrophic iceberg discharges to the North Atlantic, termed Heinrich events, punctuated the last ice age. During Heinrich events, coarse terrigenous debris released from the drifting icebergs was preserved in deep-sea sediments, serving as an indicator of iceberg passage. Quantifying the vertical flux of ice-rafted debris (IRD) in open-ocean settings can resolve questions regarding [...]
Abyssal Circulation Driven By Near-Boundary Mixing: Water Mass Transformations and Interior Stratification
Published: 2020-01-13
Subjects: Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The emerging view of the abyssal circulation is that it is associated with bottom enhanced mixing, which results in downwelling in the stratified ocean interior and upwelling in a bottom boundary layer along the insulating and sloping seafloor. In the limit of slowly-varying vertical stratification and topography, however, boundary layer theory predicts that these up- and down-slope flows largely [...]
Discriminating stacked distributary channel from palaeovalley fill sand bodies in foreland basin settings
Published: 2020-01-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Stratigraphy
Stacked fluvial distributary channel deposits and palaeovalley fills can form major, multi-storey sand bodies with similar thicknesses, and with lateral extents often greater than a single exposure. Consequently, they can be difficult to tell apart from one another using outcrop data. This study addresses this problem by quantitatively analysing the architecture of five stacked fluvial [...]
The role of natural clays in the sustainability of landfill liners
Published: 2020-01-10
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Geochemistry, Geology, Geotechnical Engineering, Physical Sciences and Mathematics
Engineered synthetic liners on their own are not the ideal solution to protect land, water and living beings against landfill leachate pollution. Despite their impermeability, engineered liners are susceptible to fail during installation and after a few years of landfill operation, and have no attenuation properties. Conversely, natural clay liners can attenuate leachate pollutants by reactions [...]
The environmental impacts of palm oil in context
Published: 2020-01-10
Subjects: Agriculture, Ecology and Evolutionary Biology, Food Science, Life Sciences, Other Food Science, Other Life Sciences, Terrestrial and Aquatic Ecology
Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15). The production of vegetable oils in general, and palm oil in particular, is perhaps the most controversial illustration of these trade-offs. Global annual demand for vegetable oil for food, animal feed and fuel is currently at 210 million tons1 (Mt), with [...]
Risk Assessment for Scientific Data
Published: 2020-01-09
Subjects: Earth Sciences, Library and Information Science, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Social and Behavioral Sciences
This is a preprint draft of the paper that was officially published in the Data Science Journal. Please quote from the published version: http://doi.org/10.5334/dsj-2020-010. Abstract: Ongoing stewardship is required to keep data collections and archives in existence. Scientific data collections may face a range of risk factors that could hinder, constrain, or limit current or future data use. [...]