Preprints
There are 5539 Preprints listed.
Structural and stratigraphic development of Offshore NW Sulawesi, Indonesia
Published: 2021-02-14
Subjects: Earth Sciences, Geology, Geomorphology, Sedimentology, Stratigraphy, Tectonics and Structure
The area of the Offshore NW Sulawesi lies between eastern Sundaland (Borneo) and the North Arm of Sulawesi. Possible influences on the basins include Paleogene rifting in the Celebes Sea and Makassar Strait, Neogene subsidence and uplift in Borneo, late Neogene subduction at the present-day North Sulawesi Trench, and displacements related to the Palu-Koro Fault. This study presents the results of [...]
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 [...]
Halokinetic modulation of sedimentary thickness and architecture: a numerical modelling approach
Published: 2021-02-13
Subjects: Earth Sciences
Subsurface salt flow can deform overlying strata and influence contemporaneous sedimentary processes. Studying salt-sediment interactions is challenging in the subsurface due to poor imaging adjacent to salt, and in the field due to the dissolution of halite. Discrete Element Modelling provides an efficient and inexpensive tool to model stratigraphy and deformation around salt structures, which [...]
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 [...]
Analysis of fine particulates from fuel burning in a reconstructed building at Neolithic Çatalhöyük, Turkey and implications for respiratory health in early settled communities
Published: 2021-02-11
Subjects: Earth Sciences
The use of wood, dung and other biomass fuels can be traced back to early prehistory. Whilst the study of prehistoric fuel use and its environmental impacts is well established, there has been little investigation of the health impacts this would have had, particularly in the Neolithic period, when people went from living in relatively small groups, to living in dense settlements. The UNESCO [...]
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 [...]
Modeling and SAR Imaging of the Sea Surface: a Review of the State-of-the-Art with Simulations
Published: 2021-02-10
Subjects: Oceanography
Among other remote sensing technologies, synthetic aperture radar (SAR) has become firmly established in the practice of oceanographic research. Despite solid experience in this field, comprehensive knowledge and interpretation of ocean/sea and vessel wave signatures on radar images are still very challenging. This is not only due to the complex mechanisms involved in the SAR imaging of moving [...]
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 [...]
Early warning for great earthquakes from characterization of crustal deformation patterns with deep learning
Published: 2021-02-10
Subjects: Earth Sciences
Although infrequent, large (Mw7.5+) earthquakes can be extremely damaging and occur on subduction and intraplate faults worldwide. Earthquake early warning (EEW) systems aim to provide advanced warning before strong shaking and tsunami onsets. These systems estimate earthquake magnitude using the early metrics of waveforms, relying on empirical scaling relationships of abundant past events. [...]
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 [...]
Creating and Promoting Gender Equity and Diversity in Professional Geological Societies: A Focus on AAPG
Published: 2021-02-10
Subjects: Education, Physical Sciences and Mathematics, Social and Behavioral Sciences
When professional organizations allow gender inequity to persist, they continually lose talented, valuable individuals who enrich and lead their groups and drive innovation. This paper presents an analysis of membership data and ways in which member contributions are recognized by the American Association of Petroleum Geologists (AAPG) between 2017-2020, in relation to gender. These are compared [...]
234U/230Th coral growth dating yields reliable ages in restricted basins despite anomalous δ234Ui values
Published: 2021-02-10
Subjects: Geochemistry, Geology, Tectonics and Structure
Late Quaternary coral growth ages from uplifted coastal regions, such as marine terraces and associated palaeoshorelines, are an essential tool used to derive tectonic and fault controlled uplift and deformation rates, and thus contribute to seismic hazard analysis and constrain past global sea levels. Fossil coral growth ages are assessed for reliability based upon whether the δ234Ui (or [...]
Reduced High-Latitude Land Seasonality in Climates with Very High Carbon Dioxide
Published: 2021-02-10
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology
Observations of warm past climates and projections of future climate change show that the Arctic warms more than the global mean, particularly during winter months. Past warm climates such as the early Eocene had above-freezing Arctic continental temperatures year-round. In this paper, we show that a reduced Arctic land seasonality with increased greenhouse gases is a robust consequence of the [...]
Impact of wave-vortical interactions on oceanic submesoscale lateral dispersion
Published: 2021-02-09
Subjects: Physical Sciences and Mathematics
Submesoscale lateral transport of a passive tracer and Lagrangian particles in the ocean is investigated by means of numerical simulations with intermediate models. Using a projection technique, the models are formulated in terms of wave-mode and vortical-mode nonlinear interactions, and they range in complexity from full Boussinesq to waves-only and vortical-modes-only models. We find that, on [...]
The impact of intermittency on bed load sediment transport
Published: 2021-02-09
Subjects: Dynamical Systems, Geomorphology, Statistical, Nonlinear, and Soft Matter Physics
Sediment transport by wind or water near the threshold of grain motion is dominated by rare transport events. This intermittency makes it difficult to calibrate sediment transport laws, or to define an unambiguous threshold for grain entrainment, both of which are crucial for predicting sediment transport rates. We present a model that captures this intermittency and show that the noisy [...]