Preprints
There are 6976 Preprints listed.
Relationships between soil chemical properties and rare earth element concentrations in the aboveground biomass of a tropical herbaceous plant
Published: 2019-07-18
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics
The geochemical behavior of rare earth elements (REE) has been mainly investigated in geological systems where they represent the best proxies for processes occurring at the interface between different media. REE concentrations, normalized with respect to the upper continental crust, were used to assess their behavior. In this study, REE geochemical behavior was investigated in plant shoots of a [...]
The Leaning Puy de Dôme
Published: 2019-07-09
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Acidic lava domes are a special monogenetic volcano type with explosive eruption hazards. Such domes raise questions about the nature of monogenetic volcanism. We study the iconic Puy de Dôme (Chaîne des Puys, Auvergne) that gave its name to dome landforms. It is asymmetric with one side more rugged and steeper than the other. Using mapping and paleomagnetism we find that it was tilted by ~20° [...]
Tectonic stress controls saucer-shaped sill geometry
Published: 2019-07-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Saucer-shaped sills are common in sedimentary basins worldwide. The saucer shape relates to asymmetric stress distributions at the sill-tip during intrusion caused by bending of the overburden. Most saucer-shaped sill models are conducted without tectonic stress. Model results are poorly correlated with natural sills in that: (1) modelled saucers are much steeper than natural sills; and (2) [...]
Finite element simulations of sill intrusion during tectonic loading
Published: 2019-07-05
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Igneous sills are common features in tectonically active regions, acting as nascent magma storage systems, or feeding eruptions at large lateral distances from the magma source. Sills reaching a critical radius, rc, relative to their initial depth, H, interact with Earth’s surface, leading to mild discordant growth at angle [theta] typically <10[deg] forming saucer-shaped sills; commonly [...]
Neoglacial trends in diatom dynamics from a small alpine lake in the Qinling Mountains of central China
Published: 2019-07-05
Subjects: Geography, Life Sciences, Physical and Environmental Geography, Social and Behavioral Sciences
During the latter stages of the Holocene, and prior to anthropogenic global warming, the Earth underwent a period of cooling called the neoglacial. The neoglacial was associated with declining summer insolation and changes to Earth surface albedo. Although impacts varied globally, in China the neoglacial was generally associated with cooler, more arid climate, which led to renewed permafrost [...]
The impact of Mg2+ ions on equilibration of Mg-Ca carbonates in groundwater and brines
Published: 2019-07-04
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
At temperatures below 50°C, the Mg2+/Ca2+ values in groundwater and brines, irrespective of their origin - either carbonaceous or siliceous rocks/sediments - show a large spread. As shown by equilibria of surface layer composition of calcite in solutions containing Mg2+ , log10 (aMg2+ /a Ca2+) vary between minus infinity and +2.3, thereby covering thermodynamical equilibria between the minerals [...]
Segmentation of the Main Himalayan Thrust inferred from geodetic observations of interseismic coupling
Published: 2019-07-04
Subjects: Computer Sciences, Earth Sciences, Environmental Sciences, Geology, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Probability, Statistics and Probability, Tectonics and Structure
Mapping the distribution of locked segments along subduction megathrusts is essential for improving quantitative assessments of seismic hazard. Previous geodetic studies suggest the Main Himalayan Thrust (MHT) is homogeneously locked (or coupled) along its complete length over a down-dip extent of ~100 km. However, an increasing number of seismological and geophysical observations suggests the [...]
Photonic seismology in Monterey Bay: Dark fiber DAS illuminates offshore faults and coastal ocean dynamics
Published: 2019-07-09
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Emerging fiber-optic sensing technology coupled to existing subsea telecommunications cables can provide access to unprecedented seafloor observations of both ocean and solid earth phenomena. During March 2018, we conducted a Distributed Acoustic Sensing (DAS) measurement campaign along a buried fiber-optic cable typically used for data transfer to and from a scientific cabled observatory [...]
The Glacial Origins of Relict Pingos, Wales, UK
Published: 2019-07-04
Subjects: Earth Sciences, Geomorphology, Glaciology, Physical Sciences and Mathematics
Ramparted depressions (doughnut-shaped debris-cored ridges with peat- and/or sediment-filled central basins) are commonly perceived to represent the relict collapsed forms of permafrost ground-ice mounds (i.e. pingos or lithalsas). In Wales, UK, ramparted depressions of Late Pleistocene age have been widely attributed to permafrost-related processes. However, a variety of alternative glacial [...]
Denoising ambient seismic field correlation functions with convolutional autoencoders
Published: 2019-07-04
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Seismic interferomestry is an established method for monitoring the temporal evolution of the Earths physical properties. We introduce a new technique to improve the precision and temporal resolution of seismic monitoring studies based on deep learning. Our method uses a convolutional denoising autoencoder, called ConvDeNoise, to denoise ambient seismic field correlation functions. The technique [...]
AI-assisted identification of stromatoporoids
Published: 2026-01-23
Subjects: Physical Sciences and Mathematics
Stromatoporoid sponge fossils were major diverse reef-builders in the Palaeozoic Era; their taxonomic identification relies on thin sections examined under transmit-ted light microscopy, where vertical and transverse skeletal elements reveal diag-nostic architectural features that vary with taxa. These elements typically appear darker than the cement-filled internal spaces, allowing [...]
From prodigious volcanic degassing to caldera subsidence and quiescence at Ambrym (Vanuatu): the influence of regional tectonics
Published: 2019-06-28
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure, Volcanology
Eruptive activity shapes volcanic edifices. The formation of broad caldera depressions is often associated with major collapse events, emplacing conspicuous pyroclastic deposits. However, caldera subsidence may also proceed silently by magma withdrawal at depth, more difficult to detect. Ambrym, a basaltic volcanic island, hosts a 12-km wide caldera and several intensely-degassing lava lakes [...]
What sets the width of a river?
Published: 2019-06-28
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Alluvial rivers are formed by, and are an expression of, the water and sediment that they convey. They are the primary arteries of water and nutrients on land, making them the lifeblood of communities and commerce. While a myriad of environmental and geological factors have been proposed to control alluvial river size, near-universal scaling relations between channel geometry and discharge [...]
Lateral variability of shelf-edge, slope and basin-floor deposits, Santos Basin, offshore Brazil
Published: 2019-06-28
Subjects: Earth Sciences, Engineering, Geology, Physical Sciences and Mathematics, Sedimentology
Construction of continental margins is driven by sediment transported across the shelf to the shelf-edge, where it is reworked by wave-, tide- and river-influenced processes within deltas and flanking clastic shorelines. Stalling of continental margin progradation often results in degradation of the outer shelf to upper slope, with re-sedimentation to the lower slope and basin-floor via a range [...]
Certified Reduced Basis Method in Geosciences Addressing the challenge of high dimensional problems
Published: 2019-06-28
Subjects: Applied Mathematics, Earth Sciences, Numerical Analysis and Computation, Partial Differential Equations, Physical Sciences and Mathematics
One of the biggest challenges in Computational Geosciences is finding ways of efficiently simulating high-dimensional problems. In this paper, we demonstrate how the RB method can be gainfully exploited to solve problems in the Geosciences. The reduced basis method constructs low-dimensional approximations to (high-dimensional) solutions of parametrized partial differential equations. In contrast [...]