Preprints
Filtering by Subject: Physical Sciences and Mathematics
The vulnerability of tidal flats and multi-channel estuaries to dredging and disposal
Published: 2019-04-05
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geomorphology, Other Civil and Environmental Engineering, Physical Sciences and Mathematics
Shipping fairways in estuaries are continuously dredged to maintain access for large vessels to major ports. However, several estuaries worldwide show adverse side effects to dredging activities, including a shift from multi-channel systems to single-channel systems and the loss of ecologically valuable intertidal flats. We used a time series of bathymetry of the Western Scheldt estuary (the [...]
Earthquake cycle modeling of the Cascadia subduction zone
Published: 2019-04-05
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The Cascadia subduction zone hosts great $\mathrm{M}_\mathrm{W} > 8.5$ earthquakes, but studying these events is hindered by our short observational record. Earthquake cycle simulation provides an alternative window into the behavior of the subduction zone. Here, we present simulations over 3,800 years, 14 ruptures and hundreds of slow slip events on a high-fidelity geometric representation of [...]
Dispersion, accumulation and the ultimate fate of microplastics in deep-marine environments: A review and future directions
Published: 2019-04-04
Subjects: Earth Sciences, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Natural Resources and Conservation, Physical Sciences and Mathematics, Sustainability
An estimated 8.3 billion tonnes of non-biodegradable plastic has been produced over the last 65 years. Much of this is not recycled and is disposed into the sedimentary system, has a long environmental residence time and accumulates in sedimentary systems worldwide, posing a threat to important ecosystems and potentially human health. We synthesise existing knowledge of seafloor microplastic [...]
Mapping geospatial processes affecting the environmental fate of agricultural pesticides in Africa
Published: 2019-04-02
Subjects: Environmental Health and Protection, Environmental Sciences, Physical Sciences and Mathematics
The application of agricultural pesticides in Africa has high negative effects on human health and the environment. To analyse the effect, spatial data characterizing the environmental fate of agricultural pesticides are needed. However, poor availability and quality of data that quantify pesticide application and pesticide fate limit direct analysis of the effect. This study selected key [...]
Determining cooling rates from mica 40Ar/39Ar thermochronology data: effect of cooling path shape
Published: 2019-04-02
Subjects: Earth Sciences, Geochemistry, Geology, Other Earth Sciences, Physical Sciences and Mathematics
Tectonic models are commonly underpinned by metamorphic cooling rates derived from diffusive-loss thermochronology data. Such cooling ages are usually linked to temperature via Dodson’s 1973 closure temperature (TC) formulation, which specifies a 1/time-shaped cooling path. Geologists, however, commonly discuss cooling rates as a linear temperature/time shape. We present the results of a series [...]
Ridge Subduction and Afterslip Control Aftershock Distribution of the 2016 Mw 7.8 Ecuador Earthquake
Published: 2019-04-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We characterise the aftershock sequence following the 2016 Mw=7.8 Pedernales earthquake. More than 10,000 events were detected and located, with magnitudes up to 6.9. Most of the aftershock seismicity results from interplate thrust faulting, but we also observe a few normal and strike-slip mechanisms. Seismicity extends for more than 300 km along strike, and is constrained between the trench and [...]
Boundary element methods for earthquake modeling with realistic 3D geometries
Published: 2019-04-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Boundary element methods have become a foundational tool in earthquake science for the modeling of earthquake cycle kinematics. Despite their wide use and convenience typical rectangular and triangular constant slip dislocation methods produce stress singularities at the edges of every element rendering these models physically unrealistic. As we demonstrate, in an earthquake cycle simulation [...]
A global survey on the perceptions and impacts of gender inequality in the Earth and space sciences
Published: 2019-04-01
Subjects: Earth Sciences, Environmental Studies, Physical Sciences and Mathematics, Social and Behavioral Sciences
The leaky pipeline phenomenon refers to the disproportionate decline of female scientists at higher academic career levels and is a major problem in the natural sciences. Identifying the underlying causes is challenging, and thus, solving the problem remains difficult. To better understand the reasons for the leaky pipeline, we assess the perceptions and impacts of gender bias and imbalance—two [...]
A simplified seasonal forecasting strategy, applied to wind and solar power in Europe
Published: 2019-04-01
Subjects: Applied Statistics, Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics, Physics, Probability, Statistics and Probability, Sustainability
We demonstrate levels of skill for forecasts of seasonal-mean wind speed and solar irradiance in Europe, using seasonal forecast systems available from the Copernicus Climate Change Service (C3S). While skill is patchy, there is potential for the development of climate services for the energy sector. Following previous studies, we show that, where there is skill, a simple linear regression-based [...]
The Cyclic Preservation of Clastic and Evaporitic Sabkha Sediments: Insights from the Cedar Mesa Sandstone Formation of the Cutler Group, Utah, USA
Published: 2019-04-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology
The strata of arid continental basins commonly comprise evaporitic sediments deposited in sabkha settings combined with clastic sediments derived from aeolian, fluvial and/or lacustrine settings. The sedimentary character of these mixed successions and the degree to which evaporitic strata influence their composition, both contribute towards the economic potential of the evaporitic and the [...]
A macroscale hydrogeological numerical model of the Suio hydrothermal system (central Italy)
Published: 2019-04-01
Subjects: Earth Sciences, Environmental Sciences, Geochemistry, Geology, Natural Resources and Conservation, Physical Sciences and Mathematics, Water Resource Management
The complex behaviour of the Suio hydrothermal system (central Italy) and its potential exploitation as a renewable energy source are still unclear. To quantitatively evaluate the geothermal resource, the Suio hydrothermal system has been investigated with a hydrogeological numerical model that couples fluid flow, thermal convection, and transport of diluted species inside a hybrid [...]
Observation and explanation of spurious seismic signals emerging in teleseismic noise correlations
Published: 2019-04-01
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Deep body waves have been reconstructed from seismic noise correlations in recent studies. The authors note their great potential for deep-Earth imaging. In addition to the expected physical seismic phases, some spurious arrivals having no correspondence in earthquake seismograms are observed from the noise correlations. The origins of the noise-derived body waves have not been well understood. [...]
Audit of Petroleum Exploration Wells in the UK Rockall Basin: 1980-2006
Published: 2019-04-01
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
The UK Rockall Basin is one of the most underexplored areas of the UK Continental Shelf (UKCS) with only 12 exploration wells drilled since 1980, in a basin area that is equal in size to the entire North Sea hydrocarbon province (NNS, CNS & SNS). With only one discovery, made in 2000 (Benbecula South 154/1-1 Gas discovery), the general view of the basin from an exploration viewpoint has not [...]
The flow of fresh groundwater and solutes to the world’s oceans and coastal ecosystems
Published: 2019-03-31
Subjects: Earth Sciences, Hydrology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The flow of fresh groundwater towards the world oceans may provide substantial inputs of nutrients and solutes to the oceans. Here we present a spatially resolved global model of coastal groundwater discharge to show that the contribution of fresh groundwater is lower than most previous estimates and accounts for only ~0.6% of the freshwater input and ~2% of the solute input to the oceans. [...]
Minimal surfaces in porous media: pore-scale imaging of multiphase flow in an altered-wettability Bentheimer sandstone
Published: 2019-03-29
Subjects: Earth Sciences, Fluid Dynamics, Physical Sciences and Mathematics, Physics
We observed features of pore scale fluid distributions during oil-brine displacement in a mixed-wet sandstone rock sample. High-resolution X-ray imaging was used in combination with differential pressure measurements to measure relative permeability and capillary pressure simultaneously during a steady-state waterflood experiment on a sample of Bentheimer sandstone 51.6 mm long and 6.1 mm in [...]