Preprints
Filtering by Subject: Physical Sciences and Mathematics
A mechanistic erosion model for cosmogenic nuclide inheritance in fluvial single-clast exposure ages
Published: 2019-08-06
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Statistics and Probability, Tectonics and Structure
Terrestrial cosmogenic nuclides (TCNs), produced by the bombardment of Earth’s surface by cosmic rays, are widely used for age-dating and pacing surface processes. Sediments carry an inherited TCN concentration, useful for quantifying erosion and transport rates, but that must be subtracted when age-dating sedimentary landforms, such as alluvial fans. Here we present a mechanistic model of [...]
Bayesian calibration of the Mg/Ca paleothermometer in planktic foraminifera
Published: 2019-08-06
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Mg/Ca ratio of planktic foraminifera is a widely-used proxy for sea-surface temperature, but is also sensitive to other environmental factors. Previous work has relied on correcting Mg/Ca for non-thermal influences. Here, we develop a set of Bayesian models for Mg/Ca in four major planktic groups -- Globigerinoides ruber (including both pink and white chromotypes), Trilobatus sacculifer, [...]
Vertical Eddy Iron Fluxes Support Primary Production in the Open Southern Ocean
Published: 2019-08-04
Subjects: Biogeochemistry, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The primary productivity of the Southern Ocean ecosystem, and associated biological carbon pump, is limited by the availability of the micronutrient iron. Riverine sediments and atmospheric dust supply iron at the ocean margins, but in the vast open ocean, iron reaches phytoplankton primarily when iron-rich sub-surface waters enter the euphotic zone, linking vertical transport processes to [...]
Assessment of the community vulnerability to extreme spring floods: The case of the Amga River, central Yakutia, Siberia
Published: 2019-08-04
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Spring floods in Sakha (Yakutia) Republic, Siberian Russia, annually induce a significant damage to the population and infrastructure of communities of this Arctic region. Most major urban settlements are protected from floods by dams and dikes, so rural areas take a heavy beat. In 2018, spring flooding severely hit numerous rural communities in the Amga River basin, central Yakutia, exposing [...]
Onset of slip partitioning under oblique convergence within scaled physical models
Published: 2019-08-04
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Oblique convergent margins host slip partitioned faults with simultaneously active strike-slip and reverse faults. Such systems defy energetic considerations that a single oblique-slip fault accommodates deformation more efficiently than multiple faults. To investigate the development of slip partitioning, we record deformation throughout scaled experiments of wet kaolin over a low convergence [...]
Introduction of covariance components in slip inversion of geodetic data following a non-uniform spatial distribution and application to slip deficit rate estimation in the Nankai Trough subduction zone
Published: 2019-08-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
When spatial distribution of observation stations has bias in geodetic slip inversion, modeling errors in the inversion scheme may result in significant unnatural short-wave components in estimated slip distribution, which overfit to data. Combined use of both land and seafloor geodetic data in slip inversion often leads to such situations. To avoid overfitting, I proposed a method to [...]
Interannual, probabilistic prediction of water resources over Europe following the heatwave and drought 2018
Published: 2019-08-01
Subjects: Earth Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The year 2018 was one of the hottest and driest years in Europe having a large impact on agriculture, ecosystems and society. The associated drought in central and northern Europe underpins the need for water resources predictions at the seasonal to interannual time scale. In this study, we propose a probabilistic, terrestrial prediction system including water resources utilizing the Terrestrial [...]
Joint sensing of bedload flux and water depth by seismic data inversion
Published: 2019-08-01
Subjects: Environmental Monitoring, Environmental Sciences, Other Environmental Sciences, Physical Sciences and Mathematics, Water Resource Management
Rivers are the fluvial conveyor belts routing sediment across the landscape. While there are proper techniques for continuous estimates of the flux of suspended solids, constraining bedload flux is much more challenging, typically involving extensive measurement infrastructure or labour-intensive manual measurements. Seismometers are potentially valuable alternatives to in-stream devices, [...]
SediNet: A configurable deep learning model for mixed qualitative and quantitative optical granulometry
Published: 2019-07-31
Subjects: Civil and Environmental Engineering, Civil Engineering, Earth Sciences, Engineering, Geomorphology, Physical Sciences and Mathematics
I describe a configurable machine-learning framework to estimate a suite of continuous and categorical sedimentological properties from photographic imagery of sediment, and to exemplify how machine learning can be a powerful and flexible tool for automated quantitative and qualitative measurements from remotely sensed imagery. The model is tested on a large dataset consisting of 400 images and [...]
Energetics of interfacial interactions of hydrocarbon fluids with kerogen and calcite using molecular modeling
Published: 2019-07-31
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Understanding the fluid-rock interactions is essential to characterize the behavior of petroleum fluids in reservoir formations. Such knowledge is difficult to obtain due to the heterogeneous nature of hydrocarbon systems. This study investigated the interactions of light oil molecules with kerogen and calcite using molecular dynamics simulations. Specifically, octane and octanthiol were used as [...]
Fracture and Weakening of Jammed Subduction Shear Zones, Leading to the Generation of Slow Slip Events
Published: 2019-07-31
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Geodetic data have revealed that parts of subduction interfaces creep steadily or transiently. Transient slow slip events (SSEs) are typically interpreted as aseismic frictional sliding. However, SSEs may also occur via mixed visco‐brittle deformation, as observed in shear zones containing mixtures (mélange) of strong fractured clasts embedded in a weak visco‐brittle matrix. We test the [...]
Internal mouth bar variability and preservation of interflood beds in low-accommodation proximal deltaic settings (Cretaceous Dakota Group, New Mexico, USA)
Published: 2019-07-31
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Mouth bars are the fundamental architectural elements of proximal deltaic successions. Understanding their internal architecture and deciphering the relative impact and complex interaction of coastal processes (fluvial-, tide- and wave-dominated) is paramount to the interpretation of ancient deltaic successions. This is particularly challenging in low-accommodation systems, because they are [...]
The Byers Basin: Jurassic-Cretaceous tectonic and depositional evolution of the forearc deposits of the South Shetland Islands and its implications for the northern Antarctic Peninsula
Published: 2019-07-31
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
This paper addresses the Jurassic–Cretaceous stratigraphic evolution of fore-arc deposits exposed along the west coast of the northern Antarctic Peninsula. In the South Shetland Islands, Upper Jurassic deep-marine sediments are uncomformably overlain by a Lower Cretaceous volcaniclastic sequence that crops out on Livingston, Snow and Low islands. U-Pb zircon ages are presented for the upper [...]
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula
Published: 2019-07-31
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical and isotopic data are sparse. We combine new geochronological (LA-ICP-MS zircon U-Pb), geochemical, [...]
Analog forecasting of extreme-causing weather patterns using deep learning
Published: 2019-07-31
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Computational Engineering, Computer Sciences, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Numerical weather prediction (NWP) models require ever-growing computing time/resources, but still, have difficulties with predicting weather extremes. Here we introduce a data-driven framework that is based on analog forecasting (prediction using past similar patterns) and employs a novel deep learning pattern-recognition technique (capsule neural networks, CapsNets) and impact-based [...]