Preprints
Filtering by Subject: Earth Sciences
Quantification and interpretation of the climate variability record
Published: 2020-05-25
Subjects: Applied Mathematics, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This paper is currently in review for Global and Planetary Change. \\ The spectral view of variability is a compelling and adaptable tool for understanding variability of the climate. In the Mitchell (1976) seminal paper, it was used to express, on one graph with log scales, a very wide range of climate variations from millions of years to days. The spectral approach is particularly useful for [...]
Deep ductile shear localization facilitates near-orthogonal strike-slip faulting in a thin brittle lithosphere
Published: 2020-05-25
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Some active fault systems comprise near-orthogonal conjugate strike-slip faults, as highlighted by the 2019 Ridgecrest and the 2012 Indian Ocean earthquake sequences. In conventional failure theory, orthogonal faulting requires a pressure-insensitive rock strength, which is unlikely in the brittle lithosphere. Here, we conduct 3D numerical simulations to test the hypothesis that near-orthogonal [...]
Fault-controlled base-of-scarp deposits
Published: 2020-05-25
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology
The term base-of-scarp is proposed for those submarine deposits controlled by a fault and physically disconnected from their more proximal counterpart located on the footwall, although genetically linked to it. These systems differ from conventional fault-controlled deltas, such as shoal- and Gilbert-type, because they are entirely subaqueous and lack equilibrium morphology — a steady-state in [...]
The influence of spreading rate and permeability on melt focusing beneath mid-ocean ridges
Published: 2020-05-25
Subjects: Earth Sciences, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics
At mid-ocean ridges, oceanic crust is emplaced in a narrow neovolcanic region on the seafloor, whereas basaltic melt that forms this oceanic crust is generated in a wide region beneath as suggested by a few geophysical surveys. The combined observations suggest that melt generated in a wide region at depths has to be transported horizontally to a small region at the surface. We present results [...]
On the thermo-poro-mechanics of chemically active faults
Published: 2020-05-21
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Geophysics and Seismology, Geotechnical Engineering, Physical Sciences and Mathematics
Shear zones in outcrops and core drillings on active faults commonly reveal two scales of localization, with centimeter to tens of meters thick deformation zones embedding much narrower zones of mm- to cm-scale. The narrow zones are often attributed to some form of fast instability such as earthquakes or slow slip events. Surprisingly, the double localisation phenomenon seem to be independent of [...]
Holocene tephrochronology of Kerguelen Archipelago, Subantarctic Indian Ocean
Published: 2020-05-21
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Volcanology
Up to now, no geochemical or geochronological data has been published about Holocene volcanic activity on the Kerguelen Archipelago. Here we present the first continuous Holocene chronology of volcanic eruptions on the archipelago. We compared sedimentological, geochronological and geochemical data from two lake sediment cores taken in two different depocenters of Lake Armor, located ca. 70 km [...]
Jarosite formation in deep Antarctic ice provides a window into acidic, water-limited weathering on Mars
Published: 2020-05-20
Subjects: Cosmochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Planetary Geochemistry, Planetary Glaciology, Planetary Sciences
Many interpretations have been proposed to explain the presence of jarosite within Martian surficial sediments, including the possibility that it precipitated within paleo-ice deposits owing to englacial weathering of dust. But until now a similar mechanism was not observed on Earth nor in other planetary settings. We report the first multi-analytical indication of jarosite formation within deep [...]
A toolbox to quickly prepare flood inundation models for LISFLOOD-FP simulations
Published: 2020-05-20
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Hydrodynamic floodplain inundation models have been popular for many years and used extensively in engineering applications. Continental scale flood studies are now achievable using such models due to the development of terrain elevation, hydrography and river width datasets with global coverage. However, deploying flood models at any scale is time-consuming since input data needs to be processed [...]
The perpetual fragility of creeping hillslopes
Published: 2020-05-18
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Soil-mantled hillslopes owe their smooth, convex shape to creep; the slow and persistent, gravity-driven motion of grains on slopes below the angle of repose. Existing models presume that soil creep occurs via mechanical displacement of grains by (bio)physical disturbances. Recent simulations, however, suggest that soil can creep without these disturbances, due to internal relaxation dynamics [...]
Human Health Benefits of the Minamata Convention on Mercury
Published: 2020-05-18
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Earth Sciences, Environmental Health and Protection, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Minamata Convention is a legally-binding international treaty aimed at reducing the anthropogenic release of mercury, a potent neurotoxin. However, its human health benefit has not been quantified on a global scale. Here we evaluate the Convention’s benefit by a coupled climate-atmosphere-land-ocean-ecosystem model and a human mercury exposure component that considers all food categories. We [...]
Probabilistic soil moisture dynamics of water- and energy-limited ecosystems
Published: 2020-05-18
Subjects: Agriculture, Agronomy and Crop Sciences Life Sciences, Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Forest Sciences, Hydrology, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Statistical Models, Statistics and Probability
This paper presents an extension of the stochastic ecohydrological model for soil moisture dynamics at a point of Rodriguez-Iturbe et al. (1999) and Laio et al. (2001). In the original model, evapotranspiration is a function of soil moisture and vegetation parameters, so that the model is suitable for water-limited environments. Our extension introduces a dependence on maximum evapotranspiration [...]
Influence of Minibasin Obstruction on Canopy Dynamics in the northern Gulf of Mexico
Published: 2020-05-18
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
In salt-detached gravity-gliding/spreading systems the detachment geometry is a key control on the downslope mobility of the supra-salt sequence. Here we used regional 3D seismic data to examine a salt-stock canopy in the northern Gulf of Mexico slope, in an area where supra-canopy minibasins subsided vertically and translated downslope above a complex base-of-salt. If thick enough, minibasins [...]
Time-Series Prediction Approaches to Forecasting Deformation in Sentinel-1 InSAR Data
Published: 2020-05-18
Subjects: Earth Sciences, Physical Sciences and Mathematics
Time series of displacement are now routinely available from satellite InSAR and are used for flagging anomalous ground motion, but not yet for forecasting. Here we test the capabilities of conventional time series analysis and forecasting methods such as SARIMA and supervised machine learning approaches such as Long Short Term Memory (LSTM) in comparison to simple function extrapolation methods. [...]
Increasing economic drought impacts in Europe with anthropogenic warming
Published: 2020-05-14
Subjects: Climate, Earth Sciences, Environmental Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics
While climate change will alter the distribution in time and space of water, quantifications of drought risk in view of global warming remain little explored. Here, we show that in Europe drought damages could strongly increase with global warming and cause a strong regional imbalance in future drought impacts. In the absence of climate action (4°C in 2100 and no adaptation) annual drought losses [...]
What is the hydrologically effective size of a catchment?
Published: 2020-05-14
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Linking human activities and climate change with their consequences for water availability is a prerequisite for sustainable water management, which is traditionally performed at topographically delineated catchments. However, inter-catchment groundwater flow results in effective catchment sizes other than sizes suggested by topography. Here, we introduce the notion of effective catchment size [...]