Preprints
There are 4726 Preprints listed.
Diatom community responses to long-term multiple stressors at Lake Gusinoye, Siberia
Published: 2018-08-28
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Global freshwater systems are threatened by multiple anthropogenic stressors via impacts on ecological structure and function necessary to maintain their health. In order to properly manage freshwater ecosystems, we must have a better understanding of the ecological response to human‐induced stressors, especially in multiple stressor environments. When long‐term observational records are scarce [...]
Powers of 10: cross-scale optimization of social agencies for rapid climate and sustainability action
Published: 2018-08-27
Subjects: Education, Environmental Sciences, Environmental Studies, Geography, International and Area Studies, Library and Information Science, Life Sciences, Medicine and Health Sciences, Physical Sciences and Mathematics, Social and Behavioral Sciences, Sustainability
Achieving the goals of the Paris Agreement and related sustainability initiatives will require halving of greenhouse gas emissions each decade from now on through to 2050, when net zero emissions should be achieved. To reach such significant reductions requires a rapid and strategic scaling of existing and emerging technologies and practices, coupled with economic and social transformation and [...]
Earthquake Swarms and Slow Slip on a Sliver Fault in the Mexican Subduction Zone
Published: 2018-08-25
Subjects: Earth Sciences, Geophysics and Seismology, Life Sciences, Physical Sciences and Mathematics
The Mexican Subduction Zone is an ideal location for studying subduction processes due to the short trench-to-coast distances that bring broad portions of the seismogenic and transition zones of the plate interface inland. Using a recently generated seismicity catalog from a local network in Oaxaca, we identified 20 swarms of earthquakes (M<5) from 2006-2012. Swarms outline what appears to be [...]
A Review of Machine Learning Applications to Coastal Sediment Transport and Morphodynamics
Published: 2018-08-23
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
A range of computer science methods termed machine learning (ML) enables the extraction of insight and quantitative relationships from multidimensional datasets. Here, we review the use of ML on supervised regression tasks in studies of coastal morphodynamics and sediment transport. We examine aspects of ‘what’ and ‘why’, such as ‘what’ science problems ML tools have been used to address, ‘what’ [...]
DEM-based Geomorphological Mapping and Landforms Characterization of a Tropical Karst Environment in Southeastern Brazil
Published: 2018-08-23
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
This work presents a 1:10,000 geomorphological mapping of an area in southeastern Brazil, based on morphometric analysis of Digital Elevation Models (DEMs), while classical methods focus on photo interpretation. Data derived from the DEM include elevation, slope gradient, slope aspect, vertical and horizontal curvatures, amplitude, elongation and wavelength of landforms. These parameters were [...]
A calibration workflow for coastal dune models
Published: 2018-08-21
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Numerical models of coastal dune growth encode feedbacks and nonlinearities between sediment transport and plant growth. The range of processes and tunable parameters involved make model calibration an important step when using models for prediction. In this paper we outline a method to calibrate models of coastal dune formation and describe the process from end to end. The first step is [...]
Controls of basement fabric on rift coupling and development of normal fault geometries: Insights from the Rukwa – North Malawi Rift
Published: 2018-08-20
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
The Rukwa Rift and North Malawi Rift Segments (RNMRS) both define a major rift-oblique segment of the East African Rift System (EARS), and although the two young rifts show colinear approaching geometries, they are often regarded as discrete rifts due to the presence of the intervening Mbozi Block uplift located in-between. This problem has been complicated by the dominance of the Rungwe volcanic [...]
Using polygonal layer-bound normal faults as tools to delimit clastic reservoirs in the Levant Basin offshore Lebanon
Published: 2018-08-19
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure
The Levant Basin offshore Lebanon contains an array of layer-bound normal faults in the Oligo-Miocene units. The faults are believed to have nucleated in soft-grained sediments similar to polygonal fault systems worldwide, and as a result are influenced by lithological heterogeneities in the host rock unit. We used 3D seismic data and amplitude extraction from offshore Lebanon to map deepwater [...]
Using bar preservation to constrain reworking in channel-dominated fluvial stratigraphy
Published: 2018-08-16
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Fluvial deposits comprising more than 80% channel facies are often thought to have accumulated during intervals of relatively slow subsidence in sedimentary basins. This interpretation stems from the conceptual model that migrating and avulsing rivers rework their own deposits during times of limited accommodation creation, preferentially removing and bypassing fine floodplain deposits. [...]
Zealandia 2008
Published: 2018-08-16
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
Zealandia is a submerged continent in the southwest Pacific Ocean that can be regarded as a rifted part of eastern Australia and West Antarctica. Described simply, the pre-Gondwana-breakup Zealandia geological record is one of a Cambrian to Early Cretaceous Gondwana convergent margin, followed by Late Cretaceous continental rifting. Arizona Geological Society Digest 22, 227-233.
Landers 1992 "reloaded": Integrative dynamic earthquake rupture modeling
Published: 2018-08-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The 1992 $M_w$ 7.3 Landers earthquake is perhaps one of the best studied seismic events. However, many aspects of the dynamics of the rupture process are still puzzling, e.g. the rupture transfer between fault segments. We present 3D spontaneous dynamic rupture simulations, incorporating the interplay of fault geometry, topography, 3D rheology, off- fault plasticity and viscoelastic attenuation. [...]
Dalangtan Saline Playa in a Hyperarid Region of Tibet Plateua-III: Correlated Multiscale Surface Mineralogy and Geochemistry Survey
Published: 2018-08-15
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
We report the first multiscale, systematic field-based testing of correlations between orbital scale advanced spaceborne thermal emission and reflection radiometer visible near-infrared (VNIR)/shortwave infrared (SWIR) reflectance and thermal infrared relative emissivity and outcrop scale Raman spectroscopy, VNIR reflectance, X-ray diffraction (XRD), and laser-induced breakdown spectroscopy [...]
Modifications to Internal Tide Conversion Parameterizations and Implementation into Barotropic Ocean Models
Published: 2018-08-15
Subjects: Civil and Environmental Engineering, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Parameterization of the tidal energy conversion from barotropic to baroclinic modes through internal tide generation over rough and steep submarine topography is a necessary dissipative force for barotropic ocean models. We present and unify two forms of parameterizations that differ by assuming that wave generation is either only due to the local topographic features, or that it includes the [...]
Weak and slow, strong and fast: How shear zones evolve in a dry continental crust (Musgrave Ranges, Central Australia)
Published: 2018-08-15
Subjects: Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The strike-slip Davenport Shear Zone in Central Australia developed during the Petermann Orogeny (~ 550 Ma) in an intracontinental lower crustal setting under dry sub-eclogite facies conditions (~ 650 °C, 1.2 GPa). This ca. 5 km wide mylonite zone encloses several large low-strain domains, allowing a detailed study of the initiation of shear zones and their progressive development. [...]
Intraplate seismic events off Sumatra: 3-D source evolution
Published: 2018-08-15
Subjects: Earth Sciences, Physical Sciences and Mathematics
Four large, dominantly strike-slip, earthquakes have occurred in recent years in the Wharton Basin off the coast of Sumatra. The southernmost was the Mw 7.9 event on 2000 June 18, followed by the largest known intraplate earthquake – the Mw 8.6 event on 2012 April 11, with an Mw 8.2 ‘aftershock’ within a few hours. The most recent Mw 7.8 event on 2016 March 2 happened in an area with no [...]