Preprints
Filtering by Subject: Earth Sciences
An Evaluation between Time-term, Reciprocal Time and Refraction Tomography Analysis Methods for obtaining 2-D shallow Seismic Velocity Models over Synthetic Traveltimes
Published: 2018-10-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Shallow seismic refraction is the principal geophysical method for environmental and engineering site investigations to image the shallow subsurface. We present an assessment of three inversion methods, namely Time-Term inversion, Reciprocal Time methods and Refraction tomography inversion by using commercial software (SeisImager™) by using a synthetic first-arrival-time dataset that was made by [...]
Disruption of Long-Term Effusive-Explosive Activity at Santiaguito, Guatemala
Published: 2018-10-19
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
Rapid transitions in eruptive activity during lava dome eruptions pose significant challenges for monitoring and hazard assessment efforts. A comprehensive understanding of the dynamic evolution of active lava dome systems requires extensive multi-parametric datasets to fully constrain and understand rapid shifts in eruptive behavior, but few such datasets have been compiled. The Santiaguito lava [...]
Advancing global flood hazard simulations by improving comparability, benchmarking, and integration of global flood models
Published: 2018-10-19
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
In recent years, a range of global flood models (GFMs) were developed, each utilizing different process descriptions as well as validation data sets and methods. To quantify the magnitude of these differences, studies assessed the performance of GFMs on the continental and catchment level. Since the default models set-ups resulted in locally marked [...]
Natural and Anthropogenic Controls on Wood Loads in River Corridors of the Rocky, Cascade, and Olympic Mountains, USA
Published: 2018-10-18
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Wood in rivers creates habitat, shapes the morphology of valley bottoms, and acts as a pool of organic carbon (OC). Effective riverine wood management depends on a robust understanding of the spatial distribution of wood throughout river networks. This motivates the analysis of wood load in relation to both reach- and basin-scale processes. We present wood load data coupled with precipitation, [...]
Holocene climate variability of Mesopotamia and its impact on the history of civilisation
Published: 2018-10-18
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Mesopotamia, known as the cradle of civilisation, gave rise to the first state-based urban societies with sophistic political hierarchies. Its rich history full of important cultural achievements was accompanied by fundamental environmental changes over the Holocene. While geo-bio-archives from the broader region reflect slightly varying climate histories, there is a clear consensus on a more [...]
The deposition and alteration history of the northeast Syrtis Major layered sulfates
Published: 2018-10-16
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
Ancient stratigraphy on Isidis Basins western margin records the history of water on early Mars. Noachian units are overlain by layered, basaltic-composition sedimentary rocks that are enriched in polyhydrated sulfates and capped by more resistant units. The layered sulfates – uniquely exposed at northeast Syrtis Major – comprise a sedimentary sequence up to 600-m thick that has undergone a [...]
Paired organic matter and pyrite δ34S records reveal mechanisms of carbon, sulfur, and iron cycle disruption during Ocean Anoxic Event 2
Published: 2018-10-15
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Sulfur (S) isotope compositions of pyrites in the sedimentary record have played an important part in our understanding of biogeochemical cycling in the geologic record. However, the kinetics of pyritization are complex and depend strongly on the reactivity and mineralogy of available iron. As a second major sink for sulfide in anoxic sediments, organic matter (OM) provides essential context for [...]
Wavelet-based analysis of ground deformation coupling satellite acquisitions (Sentinel-1, SMOS) and data from shallow and deep wells in Southwestern France
Published: 2018-10-15
Subjects: Aerospace Engineering, Applied Mathematics, Earth Sciences, Engineering, Geophysics and Seismology, Hydrology, Physical Sciences and Mathematics
Acquisitions of the Sentinel-1 satellite are processed and comprehensively analyzed to investigate the ground displacement during a 3-year period above a gas storage site in Southwestern France. Despite quite low vertical displacements (between 4 and 8 mm) compared to the noise level, the local displacements reflects the variations due to charge and discharge during summer and winter periods, [...]
Seismic observation of tsunami at island broadband stations
Published: 2018-10-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Previous studies have reported seismic observations of tsunami recorded at island broadband stations. Coastal loading by the tsunami can explain them. For further quantification, we model tsunami propagation assuming an axisymmetric structure: a conical island with a flat ocean floor. The total tsunami wavefield can be represented by superposition between an incident tsunami wave and the [...]
U–Pb dating of mineral deposits: From age constraints to ore-forming processes
Published: 2018-10-12
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
The knowledge of the timing and duration of ore-forming processes are perhaps one of the most desirable pieces of information that geologists require to draw a complete picture of the deposit and to put its genesis into a coherent regional or even global geological framework. In many cases, it represents an essential parameter for establishing detailed genetic models, and can critically impact on [...]
Structure and elasticity of phlogopite under compression: Geophysical implications
Published: 2018-10-10
Subjects: Earth Sciences, Mineral Physics, Physical Sciences and Mathematics
We investigated the response of the crystal structure, lattice parameters, and unit-cell volume of hydrous layered silicate phlogopite at conditions relevant to subduction zone settings. We have used first principles simulation based on density functional theory to calculate the equation of state and full elastic constant tensor. Based on the generalized gradient approximation, the full single [...]
Glacial hydroclimate of western North America: insights from proxy-model comparison and implications for Lake Bonneville
Published: 2018-10-09
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Decades of paleoclimate research have helped to bring the pattern of hydroclimatic change across North America during the Last Glacial Maximum (LGM) into ever sharper focus. Despite these advances, the drivers of LGM hydroclimatic variability continue to be debated at the continental to basin scale. To explore the driving mechanisms behind LGM hydroclimatic change, we compare an updated network [...]
Lake area constraints on past hydroclimate in the western United States: Application to Pleistocene Lake Bonneville
Published: 2018-10-09
Subjects: Climate, Earth Sciences, Environmental Sciences, Fresh Water Studies, Geology, Geomorphology, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Lake shoreline remnants found in basins of the western United States reflect wetter conditions during Pleistocene glacial periods. The size distribution of paleolakes, such as Lake Bonneville, provide a first-order constraint on the competition between regional precipitation delivery and evaporative demand. In this contribution we downscale previous work using lake mass balance equations and [...]
Geomorphology and Climate Interact to Control Organic Carbon Stock and Age in Mountain River Valley Bottoms
Published: 2018-10-08
Subjects: Biogeochemistry, Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Organic carbon (OC) in valley bottom downed wood and soil that cycles over short to moderate timescales represents a large, dynamic, and poorly quantified pool of carbon whose distribution and residence time affects global climate. We compare four disparate mountain river basins to show that mountain river valley bottoms store substantial estimated OC stocks in floodplain soil and downed wood. [...]
The Provision and Utility of Science and Uncertainty to Decision-Makers: Earth Science Case Studies
Published: 2018-10-08
Subjects: Earth Sciences, Physical Sciences and Mathematics
This document presents case studies that have been submitted for publication at the journal ENVIRONMENT SYSTEMS AND DECISIONS. The collective results of these case studies are analysed in a companion manuscript submitted for publication in MINERVA. These case studies have been internally and externally peer reviewed prior to submission to https://eartharxiv.org. If accepted at ENVIRONMENT SYSTEMS [...]