Preprints
Filtering by Subject: Earth Sciences
Low-temperature thermochronology as a control on vertical movements for semi-quantitative Source-to-Sink analysis: A case study for the Permian to Neogene of Morocco and surroundings
Published: 2019-05-15
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics
Continental passive margins and their hinterlands in the Atlantic realm are the locus of a significant amount of studies that evidence pre-, syn-, and post-rift episodic km-scale exhumation and burial episodes. We submit a 3-steps workflow to obtain 1) exhumation/burial rates, 2) eroded material flux, and 3) paleoreconstructions of source and sink domains. We apply this workflow in onshore [...]
Extension at the coast of the Makran subduction zone (Iran)
Published: 2019-05-14
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
In the Makran subduction zone, earthquake focal mechanisms and geodetic data indicate that the deforming prism currently experiences N-S compression. However, paleostress inversions performed on normal faults observed along the coast reveal local stress components consistent with N-S extension. Previously proposed mechanisms such as gravitational collapse are not in line with N-S compression and [...]
Representation of European hydroclimatic patterns with Self-Organizing Maps
Published: 2019-05-14
Subjects: Climate, Earth Sciences, Environmental Sciences, Hydrology, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Physics, Planetary Sciences
Self-Organizing Maps provide a powerful, non-linear technique of dimensionality reduction that can be used to identify clusters with similar attributes. Here, they were constructed from a 1000-year-long gridded palaeoclimatic dataset, namely the Old World Drought Atlas, to detect regions of homogeneous hydroclimatic variability across the European continent. A classification scheme of 10 regions [...]
Holocene sedimentary record and coastal evolution in the Makran subduction zone (Iran)
Published: 2019-05-14
Subjects: Earth Sciences, Geomorphology, Other Earth Sciences, Physical Sciences and Mathematics, Sedimentology
The Makran coast displays evidence of surface uplift since at least the Late Pleistocene, but it remains uncertain whether this displacement is accommodated by creep on the subduction interface, or in a series of large earthquakes. Here, we address this problem by looking at the short term (Holocene) history of continental vertical displacements recorded in the geomorphology and sedimentary [...]
A Novel Hybrid Finite Element-Spectral Boundary Integral Scheme for Modeling Earthquake Cycles: Application to Rate and State Faults with Low-Velocity Zones
Published: 2019-05-13
Subjects: Applied Mechanics, Earth Sciences, Engineering, Geophysics and Seismology, Mechanical Engineering, Physical Sciences and Mathematics
We present a novel hybrid finite element (FE) - spectral boundary integral (SBI) scheme that enables efficient simulation of earthquake cycles. This combined FE-SBI approach captures the benefits of finite elements in modelling problems with nonlinearities, as well as the computational superiority of SBI. The domain truncation enabled by this scheme allows us to utilize high-resolution finite [...]
Mechanisms of fault mirror formation and fault healing in carbonate rocks
Published: 2019-05-13
Subjects: Earth Sciences, Life Sciences, Mineral Physics, Physical Sciences and Mathematics
The development of smooth, mirror-like surfaces provides insight into the mechanical behaviour of crustal faults during the seismic cycle. To determine the thermo-chemical mechanisms of fault mirror formation, we investigated carbonate fault systems in seismically active areas of central Greece. Using multi-scale electron microscopy combined with Raman and electron energy loss spectroscopy, we [...]
Using a Superconducting Gravimeter in Support of Absolute Gravity Campaigning — A feasibility study
Published: 2019-05-13
Subjects: Earth Sciences, Engineering, Life Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Preparing for joint analysis of absolute gravity (AG) campaigns, this report investigates whether a stationary superconducting gravimeter (SCG) can provide a long-term stable measurement of site-dependent perturbations that help in reduction to the local value of little-$g$ and its secular rate of change. The crucial element concerns the discrimination of instrumental drift components from trends [...]
Overburden deformation induced by dyke-fed conical sandstone intrusions: insights from numerical experiments
Published: 2019-05-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Conical sandstone intrusions, as a distinct type of hydrocarbon reservoirs and carbon sequestration sites, remain poorly understood regarding their emplacement mechanics. Here, we report a numerical modelling study of conical sandstone intrusions using the two-dimensional discrete element method. We built simplified numerical models that contain bonded elastic particles with predefined mechanical [...]
Controls on structural styles and decoupling in stratigraphic sequences with double décollements during thin-skinned contractional tectonics: insights from numerical modelling
Published: 2019-05-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Six series of particle-based numerical experiments were performed to simulate thin-skinned contractional tectonics in stratigraphic sequences with double décollements during horizontal shortening. The models were assigned with varying rock competence, depth and thickness of the upper décollement, which resulted in significantly different styles of deformation and decoupling characteristics above [...]
Influence of nodular structures on fracture development in fine-grained rocks: numerical simulations based on the discrete element method
Published: 2019-05-10
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
Discrete element experiments were performed to simulate fracturing processes in nodule-bearing, fine-grained rocks. Two models that contain a collection of bonded circular particles were subjected to uniaxial compression to yield shortening and fracturing of the particle assembly. Model I with soft nodules produced incremental amount of microfractures within nodules during the early stage of [...]
On the automatic and a priori design of unstructured mesh resolution for coastal ocean circulation models
Published: 2019-05-10
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Civil and Environmental Engineering, Other Earth Sciences, Physical Sciences and Mathematics
This study investigates the design of unstructured mesh resolution and its impact on the modeling of barotropic tides along the United States East Coast and Gulf Coast (ECGC). A discrete representation of a computational ocean domain (mesh design) is necessary due to finite computational resources and an incomplete knowledge of the physical system (e.g., shoreline and seabed topography). The [...]
Complex earthquake behavior on simple faults
Published: 2019-05-10
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
While power-law distributions in seismic moment and interevent times are ubiquitous in regional catalogs, the statistics of individual faults remains controversial. Continuum fault models typically produce characteristic earthquakes or a narrow range of sizes, leading to the view that the regional statistics originates from interaction of multiple faults. I present theoretical arguments and [...]
Revising Contemporary Heat Flux Estimates for the Lena River, Northern Eurasia
Published: 2019-05-10
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
The Lena River heat flux affects the Laptev Sea hydrology. Published long-term estimates range from 14.0 to 15.7 EJ·a-1, based on data from Kyusyur, at the river outlet. A novel daily stream temperature (Tw) dataset was used to evaluate contemporary Lena R. heat flux, which is 16.4±2.7 EJ·a-1 (2002-2011), confirming upward trends in both Tw and water runoff. Our field data from Kyusyur, however, [...]
Growing primordial continental crust self-consistently in global mantle convection models
Published: 2019-05-10
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The majority of continental crust formed during the hotter Archean was composed of Tonalite-Trondhjemite-Granodiorite (TTG) rocks. In contrast to the present-day loci of crust formation around subduction zones and intra-plate tectonic settings, TTGs are formed when hydrated basalt melts at garnet-amphibolite, granulite or eclogite facies conditions. Generating continental crust requires a two [...]
A spatially resolved fluid-solid interaction model for dense granular packs/Soft-Sand.
Published: 2019-05-09
Subjects: Earth Sciences, Engineering, Materials Science and Engineering, Physical Sciences and Mathematics
Fluid flow through dense granular packs or soft sands can be described as a Darcy s flow for low injection rates, as the friction between grain-grain and grain-walls dominate the solid system behaviour. For high injection rates, fluid forces can generate grain displacement forming flow channels or ``fractures, which in turn modify local properties within the system, such as permeability and [...]