Preprints
There are 4725 Preprints listed.
Gradient-boosted equivalent sources
Published: 2021-02-25
Subjects: Earth Sciences, Geophysics and Seismology
The equivalent source technique is a powerful and widely used method for processing gravity and magnetic data. Nevertheless, its major drawback is the large computational cost in terms of processing time and computer memory. We present two techniques for reducing the computational cost of equivalent source processing: block-averaging source locations and the gradient-boosted equivalent source [...]
Shallow or deep? A reinterpretation of the Rifian Corridor’s unique sandy contourites
Published: 2021-02-25
Subjects: Climate, Earth Sciences, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Paleontology, Sedimentology, Stratigraphy
This study proposes that sandstone layers exposed in the Fez-Meknes region of Northern Morocco (Ben Allou (Sidi Chaded) and El Adergha localities), have been misinterpreted as unique examples of geostrophically-driven, deep marine (150 - 400 m water depth) sandy contourites. Instead, our independent paleontological, sedimentological, and stratigraphic analyses show that these sandstones represent [...]
Diversity, Equity, and Inclusion: tackling under-representation and recognition of talents in Geochemistry and Cosmochemistry
Published: 2021-02-25
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
Diversity, at every step along the scientific path, drives innovative research. Scientific societies, like the Geochemical Society (GS) and the European Association of Geochemistry (EAG), have a significant influence over which discoveries and innovators are celebrated. Such choices impact the future of research, and therefore influence the evolution of our discipline and its relationship to the [...]
Lithostratigraphy and chemostratigraphy of salt diapir sedimentary inclusions: unravelling Ediacaran salt–sediment interaction in the Flinders Ranges
Published: 2021-02-25
Subjects: Chemistry, Earth Sciences, Physical Sciences and Mathematics
Patawarta Diapir, located in the Central Flinders Ranges, South Australia, has been interpreted as a single allochthonous salt sheet containing Tonian-aged igneous and layered evaporite sedimentary intrasalt inclusions derived from the Callanna Group. Using detailed field mapping, petrographic analysis, and lithostratigraphic correlation within Patawarta Diapir, five primarily silty limestone [...]
Nature of the Cuvier Abyssal Plain crust, offshore NW Australia
Published: 2021-02-24
Subjects: Physical Sciences and Mathematics
Magnetic stripes have long been assumed to be indicative of oceanic crust. However, continental crust heavily intruded by magma can also record magnetic stripes. We re-evaluate the nature of the Cuvier Abyssal Plain (CAP), offshore NW Australia, which hosts magnetic stripes and has previously been defined as oceanic crust. We show chemical data from a basalt within the CAP, previously described [...]
No cryosphere-confined aquifer below InSight on Mars
Published: 2021-02-24
Subjects: Planetary Geophysics and Seismology, Planetary Hydrology, Planetary Sciences
The seismometer deployed by the InSight lander measured the seismic velocity of the Martian crust. We use a rock physics model to interpret those velocities and constrain hydrogeological properties. The seismic velocity of the upper ~10 km is too low to be ice-saturated. Hence there is no cryosphere that confines deeper aquifers. An increase in seismic velocity at depths of ~10 km could be [...]
Episodicity and Migration of Low Frequency Earthquakes modeled with Fast Fluid Pressure Transients in the Permeable Subduction Interface
Published: 2021-02-24
Subjects: Geophysics and Seismology
In many subduction zones, the plate interface hosts intermittent, low-frequency, low-magnitude seismic tremor and low-frequency earthquakes (LFEs). Seismic activity clusters in episodic bursts that migrate along the fault zone in complex ways. Geological structures in fossil tremor source regions testify to large and pervasive variations of fluid pressure and permeability. Here, we explore the [...]
Stable a posteriori LES of 2D turbulence using convolutional neural networks: Backscattering analysis and generalization to higher Re via transfer learning
Published: 2021-02-24
Subjects: Engineering
There is a growing interest in developing data-driven subgrid-scale (SGS) models for large-eddy simulation (LES) using machine learning (ML). In a priori (offline) tests, some recent studies have found ML-based data-driven SGS models that are trained on high-fidelity data (e.g., from direct numerical simulation, DNS) to outperform baseline physics-based models and accurately capture [...]
Evidence for crustal removal, tectonic erosion and flare-ups from the Japanese evolving forearc sediment provenance
Published: 2021-02-24
Subjects: Earth Sciences, Geochemistry, Geology, Tectonics and Structure
Forearc basins preserve the geologic record relating strictly to arc magmatism. The provenance of forearc sediment can be used to differentiate periods of crustal growth, accretion, and destruction, enhanced magmatism, advancing and retreating subduction slabs, delamination, etc. All these tectonic events systems predict differing degrees of sedimentary reworking of the older forearc units. [...]
Global climate-driven trade-offs between the water retention and cooling benefits of urban greening
Published: 2021-02-24
Subjects: Civil and Environmental Engineering, Construction Engineering and Management, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Heat-related mortality and flooding are pressing challenges for the >4 billion urban population worldwide, exacerbated by increasing urbanization and climate change. Urban greening, such as green roofs and parks, can potentially help address both problems, but the geographical variation of the relative hydrological and thermal performance benefits of such interventions are unknown. Here we [...]
Displacing fishmeal with protein derived from stranded methane
Published: 2021-02-23
Subjects: Bioresource and Agricultural Engineering, Civil and Environmental Engineering, Engineering, Environmental Engineering
Methane emitted and flared from industrial sources across the United States is a major contributor to global climate change. Methanotrophic bacteria can transform this methane into useful protein-rich biomass for animal feed. In the rapidly growing aquaculture industry, this can replace ocean-caught fishmeal, reducing demands on over-harvested fisheries. Here, we analyze the economic potential of [...]
A record of plume-induced plate rotation triggering seafloor spreading and subduction initiation
Published: 2021-02-23
Subjects: Earth Sciences, Geology, Tectonics and Structure
The formation of a global network of plate boundaries surrounding a mosaic of lithospheric fragments was a key step in the emergence of Earth’s plate tectonics. So far, propositions for plate boundary formation are regional in nature but how plate boundaries are being created over 1000s of km in short periods of geological time remains elusive. Here, we show from geological observations that a [...]
Capturing the spatial variability of algal bloom development in a shallow temperate lake
Published: 2021-02-23
Subjects: Terrestrial and Aquatic Ecology
1. Algal blooms can have profound effects on the structure and function of aquatic ecosystems and have the potential to interrupt valuable ecosystem services. Despite the potential ecological and economic consequences of algal blooms, the spatial dynamics of bloom development in spatially complex ecosystems such as shallow lakes remain poorly characterized. Our goal was to evaluate the magnitude [...]
The Plastic Pathfinder: A Macroplastic Transport and Fate Model for Terrestrial Environments
Published: 2021-02-22
Subjects: Other Environmental Sciences
Land-based plastic waste is the major source for freshwater and marine plastic pollution. Yet, the transport pathways over land remain highly uncertain. Here, we introduce a new conceptual model to forecast plastic transport on land: the Plastic Pathfinder; a numerical model that simulates the spatiotemporal distribution of macroplastic (>0.5 cm) at a river basin scale. The plastic transport [...]
A database of submarine landslides offshore West and Southwest Iberia
Published: 2021-02-22
Subjects: Earth Sciences, Geology
Submarine landslides are major geohazards occurring on distinct seabed domains ranging from shallow coastal areas to the deeper points of the ocean. The nature and relief of the seabed are key factors influencing the location and size of submarine landslides. Efforts have recently been made to compile databases of submarine landslide distribution and morphometry, a crucial task to assess [...]