Preprints
There are 7996 Preprints listed.
Evaluating the geochemistry and paired silicon and oxygen isotope record of quartz in siliceous rocks from the ~3 Ga Buhwa Greenstone Belt, Zimbabwe, a critical link to deciphering the Archean silica cycle
Published: 2020-11-10
Subjects: Physical Sciences and Mathematics
The balance of the Archean silica cycle links fundamentally to large scale processes that govern the composition of the ocean. Shifting contributions from continental or hydrothermal inputs of silica to the ocean is commonly recorded in silica-rich chemical precipitates. Such information is critical to interpreting primordial conditions in early life environments but reading the archive of [...]
Examining the impact of the Great Barrier Reef on tsunami propagation using numerical simulations
Published: 2020-11-09
Subjects: Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Coral reefs may provide a beneficial first line of defence against tsunami hazards, though this is currently debated. Using a fully nonlinear, Boussinesq propagation model, we examine the buffering capacity of the Great Barrier Reef against tsunamis triggered by several hypothetical sources: a series of far-field, Solomon Islands earthquake sources of various magnitudes (Mw 8.0, Mw 8.5, and Mw [...]
Utilizing Distributed Acoustic Sensing and Ocean Bottom Fiber Optic Cables for Submarine Structural Characterization
Published: 2020-11-09
Subjects: Geophysics and Seismology, Oceanography
The sparsity of permanent seismic instrumentation in marine environments often limits the availability of subsea information on geohazards, including active fault systems, in both time and space. One sensing resource that may provide observational access to the seafloor environment are existing networks of ocean bottom fiber optic cables; these cables, coupled to modern distributed acoustic [...]
Global lockdown potential impact on achieving Sustainable Development Goals
Published: 2020-11-17
Subjects: Environmental Studies, Life Sciences
Coronavirus disease (COVID-19) pandemic has led to a lockdown worldwide. This restriction on human movements and activities significantly influences society and the environment. We examined the consequences of global lockdown for human movement and nitrogen dioxide (NO2) emissions using an air pollution index and dataset and satellite image analyses. We also evaluated the immediate (during [...]
The effects of 180 years of aging on the physical and seismic properties of partially saturated sands
Published: 2020-11-12
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics, Sedimentology
Constraining how the physical properties and seismic responses of recently deposited sands change with time is important for understanding earthquake site response, subsurface fluid flow, and early stages lithification. Currently, however, there is no detailed (cm-scale) assessment of how sand physical properties and associated seismic velocities evolve over the first two centuries after [...]
On the use of rock physics models for studying the critical zone
Published: 2020-11-12
Subjects: Geophysics and Seismology, Physical Sciences and Mathematics, Sedimentology
How effective are rock physics models for relating seismic velocities to the physical properties of sediments, fluids, and cement within the critical zone, and what factors most substantially influence the models’ accuracies? We answer these questions by testing and analyzing the accuracies of seven rock physics models (Hertz-Mindlin, Walton, Jenkins, Digby, stiff sand, soft sand, and contact [...]
Radiocarbon Protocols and First Intercomparison Results from the Chronos 14Carbon-Cycle Facility, University of New South Wales, Sydney, Australia
Published: 2020-11-12
Subjects: Physical Sciences and Mathematics
The Chronos 14Carbon-Cycle Facility is a new radiocarbon laboratory at the University of New South Wales, Australia. Built around an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) Accelerator Mass Spectrometer (AMS) installed in October 2019, the facility was established to address major challenges in the Earth, Environmental and Archaeological sciences. Here we report an overview of the [...]
Microseismicity appears to outline highly coupled regions on the Central Chile megathrust
Published: 2020-11-12
Subjects: Physical Sciences and Mathematics
We compiled a novel microseismicity catalog for the Central Chile megathrust (29-35◦S), comprising 8750 earthquakes between 04/2014 and 12/2018. These events describe a pattern of three trenchward open half-ellipses, consisting of a continuous, coast-parallel seismicity band at 30-45 km depth, and narrow elongated seismicity clusters that protrude to the shallow megathrust and separate largely [...]
The Influence of Dust Levels on Atmospheric Carbon Dioxide and Global Temperature
Published: 2020-11-13
Subjects: Physical Sciences and Mathematics
The purpose of this paper is to examine the causality between DUST, CO2 and temperature for the Vostok ice core data series [Vostok Data Series], dating from 420 000 years ago, and the EPICA C Dome data going back 800 000 years. In addition, the time-varying volatility and coefficient of variation in the CO2, dust and temperature is examined, as well as their dynamic correlations and [...]
ENSO Drives Child Undernutrition in the Global Tropics
Published: 2020-11-12
Subjects: Applied Statistics, Climate, Environmental Public Health, Environmental Sciences, Environmental Studies, Other Environmental Sciences, Public Health, Social and Behavioral Sciences, Sustainability
The El Nino Southern Oscillation (ENSO) is a principal component of global climate variability known to influence a host of social and economic outcomes, but its systematic effects on human health remain poorly understood. We estimate ENSO’s association with child nutrition at global scale by combining variation in ENSO intensity from 1986-2018 with children’s height and weight from 186 surveys [...]
Boron isotopic signatures of melt inclusions from North Iceland reveal recycled material in the Icelandic mantle source
Published: 2020-11-13
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Volcanology
Trace element and volatile heterogeneity in the Earth's mantle is in?uenced by the recycling of oceanic lithosphere through subduction. Oceanic island basalts commonly have high concentrations of volatiles compared to mid-ocean ridge basalts, but the extent to which this enrichment is linked to recycled mantle domains remains unclear. Boron is an ideal tracer of recycled subducted material, since [...]
International Meeting 40 years of the 1980 Azores Earthquake, 6th - 7th October 2020 - Conference Report
Published: 2020-11-16
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Geophysics and Seismology, Other Civil and Environmental Engineering
The main goal of the International Meeting “40 Years of the 1980 Azores Earthquake” was promoting a reflection of the earthquake of January 1st, 1980, and the advances since them on topics like seismology, seismic hazard, and risk, building rehabilitation and public policies. Nevertheless, due to the COVID-19 outbreak, the organizing committee decided that the meeting should be online and [...]
Radiative feedbacks on land surface change and associated tropical precipitation shifts
Published: 2020-11-17
Subjects: Physical Sciences and Mathematics
Changes in land surface albedo and land surface evaporation modulate the atmospheric energy budget by changing temperatures, water vapor, clouds, snow and ice cover, and the partitioning of surface energy fluxes. Here idealized perturbations to land surface properties are imposed in a global model to understand how such forcings drive shifts in zonal mean atmospheric energy transport and zonal [...]
How fast can minibasins translate down a slope? Observations from 2D numerical models
Published: 2020-11-18
Subjects: Earth Sciences, Physical Sciences and Mathematics
Minibasins are important features in salt-bearing basins and they are mostly found in salt-detached continental slopes where the sedimentary cover undergoes seaward translation. One question which is relevant to understand the structural evolution of salt-detached slopes is how fast can the sedimentary cover and the minibasins translate. The aim of this study is three-fold: 1) to compare [...]
Architecture and sequence stratigraphy of the Upper Coralline Limestone formation, Malta – implications for Eastern Mediterranean restriction prior to the Messinian Salinity Crisis
Published: 2020-11-18
Subjects: Geology, Sedimentology, Stratigraphy
The Eastern and Western Mediterranean are separated by an elevated plateau that regulates water exchange between these two basins. The Maltese archipelago, situated atop this topographic high, offers a unique window into the evolution of this plateau in the lead up to the Messinian Salinity Crisis (MSC). The Upper Coralline Limestone formation was deposited between the late Tortonian and the [...]