Preprints
Filtering by Subject: Physical Sciences and Mathematics
Quantifying relationships between environmental factors and power dissipation on the most prolific days in the largest tornado ‘outbreaks’
Published: 2018-11-20
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
An outbreak can occur as a single day or a multi-day event characterized by many tornadoes associated with specific regional scale environmental factors. The objective of this research is to quantify the relationship between environmental factors and tornado activity using big tornado days that occur in the largest multi-day groups in the United States. First, the largest groups across space and [...]
Applications of Deep Learning to Ocean Data Inference and Sub-Grid Parameterisation
Published: 2018-11-20
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Oceanographic observations are limited by sampling rates, while ocean models are limited by finite resolution and high viscosity and diffusion coefficients. Therefore both data from observations and ocean models lack information at small-scales. Methods are needed to either extract information, extrapolate, or up-scale existing oceanographic datasets, to account for the unresolved physical [...]
Earth Science is Ready for Preprints: The First Year of EarthArXiv
Published: 2018-11-13
Subjects: Earth Sciences, Education, Physical Sciences and Mathematics
Preprints — scholarly papers that precede publication in a peer-reviewed journal — speed the delivery and accessibility of academic work and lead to faster reuse by the scientific community, as evidenced by rapid citations and social media discussions. In the past year, EarthArXiv has emerged as a community-led initiative devoted to open scholarly communication. EarthArXiv became the first [...]
Simulated environmental photo- and auto-oxidation of ambrein
Published: 2018-11-12
Subjects: Environmental Sciences, Medicine and Health Sciences, Other Environmental Sciences, Physical Sciences and Mathematics
In alcoholic solutions (tinctures), the tricyclic triterpenoid alcohol, ambrein, which is usually the main ingredient of the natural product ambergris, undergoes photo-oxidation to a number of odorous products. Such tinctures are valuable in perfumery. Similar reactions are thought to occur in the marine environment, when flotsam and jetsam ambergris are exposed to sunlight. However, [...]
Rapid and accurate estimates of streamflow depletion caused by groundwater pumping using analytical depletion functions
Published: 2018-11-12
Subjects: Civil and Environmental Engineering, Civil Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydrology, Natural Resources Management and Policy, Physical Sciences and Mathematics, Water Resource Management
Reductions in streamflow due to groundwater pumping (‘streamflow depletion’) can negatively impact water users and aquatic ecosystems but are challenging to estimate due to the time and expertise required to develop numerical models often used for water management. Here, we develop analytical depletion functions, which are simpler approaches consisting of (i) stream proximity criteria which [...]
A Small Scale Study of the Weathering Rates of Marble Gravestones Dated from 1958-1962
Published: 2018-11-12
Subjects: Earth Sciences, Environmental Sciences, Geology, Physical Sciences and Mathematics
Marble is known to weather quicker when exposed to air pollution. This has led to the suggestion that gravestones could be used to study the long term degradation of marble and be used as indicators of past pollution levels. This small scale study examined the weathering rates of a group of marble gravestones of similar age and location. The study found no evidence to suggest that these [...]
Early and persistent supershear rupture of the 2018 Mw 7.5 Palu earthquake
Published: 2018-11-09
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Supershear earthquakes with rupture velocity exceeding shear-wave speeds, previously observed in laboratory experiments and large strike-slip events, often have an initial sub-shear stage before they transition to supershear. In this study, integrated geophysical observations of the 2018 Mw 7.5 Palu, Indonesia earthquake, provide robust evidence of an early and persistent supershear rupture [...]
A Simple Model for Deglacial Meltwater Pulses
Published: 2018-11-08
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
Evidence from radiocarbon dating and complex ice sheet modeling suggests that the fastest rate of sea level rise in Earths recent history coincided with collapse of the ice saddle between the Laurentide and Cordilleran ice sheets during the last deglaciation. In this study, we derive a simple, two-equation model of two ice sheets intersecting in an ice saddle. We show that two conditions are [...]
Co-location of the downdip end of seismic coupling and the continental shelf break
Published: 2018-11-08
Subjects: Earth Sciences, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics
Along subduction margins, the morphology of the near shore domain records the combined action of erosion from ocean waves and permanent tectonic deformation from the convergence of plates. We observe that at subduction margins around the globe, the edge of continental shelves tends to be located above the downdip end of seismic coupling on the megathrust (locking depth). Coastlines lie farther [...]
An investigation of multi-fault rupture scenarios using a variety of Coulomb stress modelling criteria: methods paper and full results
Published: 2018-11-07
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
A series of Coulomb stress models are used to simulate the independently-derived (Holden et al., 2011) rupture process of Mw 7.1 Darfield earthquake. The 7-fault source model of Beavan et al. (2012) is used for all models. Model differences include (i) differences in the static stress thresholds (0,1,5,10 MPa) that must be reached or exceeded to initiate rupture on a receiver fault, (ii) [...]
How do sea-level curves influence modeled marine terrace sequences?
Published: 2018-11-07
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics, Tectonics and Structure
Sequences of uplifted marine terraces are widespread and reflect the interaction between climatic and tectonic processes at multiple scales, yet their analysis is typically biased by the chosen sea-level (SL) curve. Here we explore the influence of Quaternary SL curves on the geometry of marine terrace sequences using landscape evolution models (LEMs). First, we modeled the young, rapidly [...]
A PCA-based framework for determining remotely-sensed geological surface orientations and their statistical quality
Published: 2018-11-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Planetary Geology, Planetary Sciences, Planetary Sedimentology, Statistical Methodology, Statistics and Probability, Stratigraphy, Tectonics and Structure
The orientations of planar rock layers are fundamental to our understanding of structural geology and stratigraphy. Remote-sensing platforms including satellites, unmanned aerial vehicles (UAVs), and LIDAR scanners are increasingly used to build three-dimensional models of structural features on Earth and other planets. Remotely-gathered orientation measurements are straightforward to calculate [...]
Preservation of autogenic processes and allogenic forcings within set-scale aeolian architecture II: the scour-and-fill dominated Jurassic Page Sandstone, Arizona, USA
Published: 2018-11-07
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
The stratigraphic architecture of aeolian sandstones is thought to record signals originating from both autogenic dune behavior and allogenic environmental boundary conditions within which the dune field evolves. Mapping of outcrop-scale surfaces and sets of cross-strata between these surfaces for the Jurassic Page Sandstone near Page, Arizona, USA, demonstrates that the stratigraphic signature [...]
Growth folds above propagating normal faults
Published: 2018-11-07
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Stratigraphy, Tectonics and Structure
Growth folds above the upper tips of normal faults are ubiquitous in extensional settings, especially during the early phases of extension and in salt-rich basins. As slip accumulates on the underlying normal fault, the geometry and size of the fold changes. These changes reflect the dip, throw, displacement and propagation rate of the underlying normal fault, as well as the thickness and [...]
Spatial variability of late Holocene and 20th century sea-level rise along the Atlantic coast of the United States
Published: 2018-11-06
Subjects: Climate, Earth Sciences, Environmental Sciences, Geology, Geomorphology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Sedimentology
Accurate estimates of global sea-level rise in the pre-satellite era provide a context for 21st century sea-level predictions, but the use of tide-gauge records is complicated by the contributions from changes in land level due to glacial isostatic adjustment (GIA). We have constructed a rigorous quality-controlled database of late Holocene sea-level indices from the U.S. Atlantic coast, [...]