Preprints
Filtering by Subject: Physical Sciences and Mathematics
A Reduced Order Approach for Probabilistic Inversions of 3D Magnetotelluric Data II: Joint inversion of MT and Surface-Wave Data
Published: 2021-02-25
Subjects: Physical Sciences and Mathematics
Joint probabilistic inversions of magnetotelluric (MT) and seismic data has great potential for imaging the thermochemical structure of the lithosphere as well as mapping fluid/melt pathways and regions of mantle metasomatism. In this contribution we present a novel probabilistic (Bayesian) joint inversion scheme for 3D MT and surface-wave dispersion data particularly designed for large-scale [...]
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: 2021-02-24
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 [...]
Global climate-driven trade-offs between the water retention and cooling benefits of urban greening
Published: 2021-02-23
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 [...]
A baseline for microplastic particle occurrence and distribution in Great Bay Estuary
Published: 2021-02-18
Subjects: Life Sciences, Physical Sciences and Mathematics
We extracted and analyzed microplastics (MP) in archived sediment cores from Great Bay Estuary (GBE) in the Gulf of Maine region of North America. Results indicated that MP are distributed in GBE sediments, 0-30 cm, at an average occurrence of 116 ± 21 particles g-1 and that morphology varies by site and depth. Analysis by sediment depth and age class indicated that MP accumulation increased over [...]
Accelerating the Lagrangian particle tracking of residence time distributions and source water mixing towards large scales
Published: 2021-02-18
Subjects: Physical Sciences and Mathematics
Travel/residence time distributions (TTDs/RTDs) are important tools to evaluate the vulnerability of catchments to contamination and understand many aspects of catchment function and behavior. In recent years, the calculation of TTDs/RTDs based on the Lagrangian particle tracking approach together with the integrated hydrologic modeling has become a popular counterpart to analytical approaches [...]
Insights into the nature of plume-ridge interaction and outflux of H2O from the Galápagos Spreading Centre
Published: 2021-02-18
Subjects: Earth Sciences, Geochemistry, Other Earth Sciences, Physical Sciences and Mathematics, Volcanology
The flow of high-temperature and compositionally-enriched material between mantle plumes and nearby spreading centres influences up to 30% of the global mid-ocean ridge system and represents a significant, but currently unconstrained, flux of volatiles out of the mantle. Here we present new analyses of H2O, F, Cl and S in basaltic glass chips from an archetypal region of plume-ridge interaction, [...]
Laponite gels - visco-elasto-plastic analogues for geological laboratory modelling
Published: 2021-02-16
Subjects: Physical Sciences and Mathematics
Laponite ® is a synthetic clay that, depending on concentration, temperature and curing time, forms a clear, transparent thixotropic fluid or brittle visco-elasto-plastic gel when mixed with water. Here we present the results of rheological and mechanical testing of gel-forming Laponite RD (LRD) to evaluate its suitability as a rock analogue in laboratory analogue experiments. Rheological tests [...]
Co- and postseismic slip behaviors extracted from decadal seafloor geodesy after the 2011 Tohoku-oki earthquake
Published: 2021-02-16
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics
Investigations of the co- and postseismic processes of the 2011 Tohoku-oki earthquake provide essential information on the seismic cycle in the Japan Trench. Although various postseismic models have been proposed, no consensus has been reached, especially on the along-strike extensions of the main rupture due to the lack of conclusive evidence, even in the coseismic process. To decompose the [...]
Numerical modeling of Earth's dynamic surface: a community approach
Published: 2021-02-14
Subjects: Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Geology, Geomorphology, Glaciology, Hydrology, Numerical Analysis and Scientific Computing, Other Environmental Sciences, Physical Sciences and Mathematics, Sedimentology, Soil Science, Stratigraphy
Computational modelling occupies a unique niche in Earth environmental sciences. Models serve not just as scientific technology and infrastructure, but also as digital containers of the scientific community's understanding of the natural world. As this understanding improves, so too must the associated software. This dual nature---models as both infrastructure and hypotheses---means that [...]
Two-sided turbulent surface layer parameterizations for computing air-sea fluxes
Published: 2021-02-13
Subjects: Physical Sciences and Mathematics
Standard methods for determining air – sea fluxes typically rely on bulk algorithms set in the frame of Monin-Obukhov stability theory (MOST), using ocean surface fields and atmosphere near-surface fields. In the context of coupled ocean – atmosphere simulations, the shallowest ocean vertical level is usually used as bulk input and by default, the turbulent closure is one-sided: it extrapolates [...]
High-resolution observations of the North Pacific transition layer from a Lagrangian float
Published: 2021-02-11
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
A crucial region of the ocean surface boundary layer (OSBL) is the strongly-sheared and -stratified transition layer (TL) separating the mixed layer from the upper pycnocline, where a diverse range of waves and instabilities are possible. Previous work suggests that these different waves and instabilities will lead to different OSBL behaviours. Therefore, understanding which physical processes [...]
Using Landsat and Sentinel Imagery to Monitor Alfalfa and Grass Pastures in Western Colorado
Published: 2021-02-10
Subjects: Engineering, Physical Sciences and Mathematics
Crop phenology of alfalfa and grass pasture fields on the western slope of Colorado, USA, was tracked using an NDVI time series derived from Landsat 7 (ETM+), Landsat 8 (OLI) and Sentinel 2a MSI to obtain high temporal frequency information of crop growth stages. These perennial pastures, which occupy a majority of irrigated land in the region and typically have more than one growing/cutting [...]
Improving the Robustness of the Comparison Model Method for the Identification of Hydraulic Transmissivities
Published: 2021-02-10
Subjects: Engineering, Physical Sciences and Mathematics
The Comparison Model Method (CMM) is a relatively simple and computationally efficient direct method for the identification of the transmissivity of a confined aquifer by solution of an inverse problem. However, it suffers some of the classical drawbacks related to ill-posedness and ill-conditioning of inverse methods. Effectiveness of the CMM can be improved by some approaches. First of all, the [...]