Preprints
There are 5933 Preprints listed.
The precession constant and its long-term variation
Published: 2020-12-08
Subjects: Astrophysics and Astronomy, Earth Sciences, Physical Sciences and Mathematics, Planetary Sciences
The dynamical flattening of the Earth, H, related to the precession constant, is a fundamental astro-geodetic parameter that appears in studies of the Earth's rotation and orbital evolution. We present numerical predictions and observations of the variation in H over time scales ranging from tens of millions of years to decades. The geophysical processes controlling this variation include [...]
VESIcal Part I: An open-source thermodynamic model engine for mixed volatile (H2O-CO2) solubility in silicate melts
Published: 2020-12-08
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Planetary Geochemistry, Planetary Geology, Planetary Sciences, Volcanology
Thermodynamics has been fundamental to the interpretation of geologic data and modeling of geologic systems for decades. However, more recent advancements in computational capabilities and a marked increase in researchers’ accessibility to computing tools has outpaced the functionality and extensibility of currently available modeling tools. Here we present VESIcal (Volatile Equilibria and [...]
International disparities in open access practices in the Earth Sciences
Published: 2020-12-08
Subjects: Earth Sciences, Physical Sciences and Mathematics
Background. Open Access (OA) describes the free, unrestricted access to and re-use of research articles. Recently, a new wave of interest, debate, and practice surrounding OA publishing has emerged. Objectives. The paper presented here focuses on international disparities in OA publication practices of the Earth Science community. We aim to provide an overview of actual publication practices and [...]
Planted mangroves cap toxic oil spill
Published: 2020-12-07
Subjects: Life Sciences
Mangroves are known to provide many ecosystem services, however there is little information on their potential role to cap and immobilise toxic levels of total petroleum hydrocarbons (TPH). Using an Australian case study, we investigated the capacity of planted mangroves (Avicennia marina) to immobilise TPH within a small embayment subjected to multiple oil spills throughout the 1980s. Mangroves [...]
Conditions for aeolian transport in the Solar System
Published: 2020-12-06
Subjects: Planetary Geomorphology
Sand dunes arise wherever loose sediment is mobilized by winds that exceed threshold speeds, and grains are sufficiently strong to survive collisions. The ubiquity of dunes in our solar system is remarkable and confounding; their occurrence under conditions of thin atmospheres, and/or friable materials, challenges our understanding of sediment transport mechanics. Current threshold theories lose [...]
Reconstructing Magma Storage Depths for the 2018 Kīlauean Eruption from Melt inclusion CO2 Contents: The Importance of Vapor Bubbles
Published: 2020-12-04
Subjects: Earth Sciences
The 2018 lower East Rift Zone (LERZ) eruption and the accompanying collapse of the summit caldera marked the most destructive episode of activity at Kīlauea Volcano in the last 200 years. The eruption was extremely well-monitored, with extensive real-time lava sampling as well as continuous geodetic data capturing the caldera collapse. This multi-parameter dataset provides an exceptional [...]
Assessment of quartz grain growth and the application of the wattmeter to predict recrystallized grain sizes
Published: 2020-12-04
Subjects: Geology, Mineral Physics, Tectonics and Structure
We investigated relationships between the recrystallized grain size and stress in experimentally deformed water-added quartz aggregates. For stresses >100 MPa there is a variation in the measured recrystallized grain size for a given stress. We found this variation correlates with a change in the c-axis fabric in general shear experiments, where samples with larger recrystallized grain sizes for [...]
Global Liquefied Natural Gas Expansion Exceeds Demand for Coal-to-gas Switching in Paris Compliant Pathways
Published: 2020-12-04
Subjects: Oil, Gas, and Energy, Sustainability
The shift from coal to natural gas (NG) in the power sector has led to significant reductions in carbon emissions. The shale gas revolution that led to this shift is now fueling a global expansion in liquefied natural gas (LNG) export infrastructure. In this work, we assess the viability of LNG expansion to reduce global carbon emissions through coal-to-gas switching in the power sector under [...]
An Active Learning Pipeline to Detect Hurricane Washover in Post-Storm Aerial Images
Published: 2020-12-02
Subjects: Environmental Monitoring, Geomorphology, Physical Sciences and Mathematics
We present an active learning pipeline to identify hurricane impacts on coastal landscapes. Previously unlabeled post-storm images are used in a three component workflow — first an online interface is used to crowd-source labels for imagery; second, a convolutional neural network is trained using the labeled images; third, model predictions are displayed on an interactive map. Both the labeler [...]
Stalagmite carbon isotopes suggest deglacial increase in soil respiration in Western Europe driven by temperature change
Published: 2020-12-02
Subjects: Biogeochemistry, Climate, Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Speleology
The temperate region of Western Europe underwent dramatic climatic and environmental change during the last deglaciation. Much of what is known about the terrestrial ecosystem response to deglacial warming stems from pollen preserved in sediment sequences, providing information on vegetation composition. Other ecosystem processes, such as soil respiration, remain poorly constrained over past [...]
Coordination numbers in natural beach sand
Published: 2020-12-02
Subjects: Geophysics and Seismology, Geotechnical Engineering, Sedimentology
Coordination number controls elastic moduli, seismic velocity, and force transmission in sands and is thus a critical factor controlling the resistance of sands to deformation. Previous studies quantified relationships between coordination number, porosity, grain size, sphericity, and effective stress in pluviated or modeled sands. Here, we determine if these relationships hold in [...]
Listening for the Landing: Detecting Perseverance’s landing with InSight
Published: 2020-12-02
Subjects: Physical Sciences and Mathematics
The entry, descent, and landing (EDL) sequence of NASA's Mars 2020 Perseverance rover will act as a seismic source of known temporal and spatial localization. We evaluate whether the signals produced by this event will be detectable at the InSight lander (3452~km away), comparing expected signal amplitudes to noise levels at the instrument. Modeling is undertaken to predict the propagation of the [...]
Operationalising coastal resilience to flood and erosion hazard: A demonstration for England
Published: 2020-12-02
Subjects: Geomorphology, Nature and Society Relations, Physical and Environmental Geography, Sustainability
Resilience is widely seen as an important attribute of coastal systems and, as a concept, is increasingly prominent in policy documents. However, there are conflicting ideas on what constitutes resilience and its operationalisation as an overarching principle of coastal management remains limited. In this paper, we show how resilience to coastal flood and erosion hazard could be measured and [...]
Recording earthquakes for tomographic imaging of the mantle beneath the South Pacific by autonomous MERMAID floats
Published: 2020-12-02
Subjects: Geophysics and Seismology
We present the first 16 months of data returned from a mobile array of 16 freely floating diving instruments, named MERMAID for Mobile Earthquake Recording in Marine Areas by Independent Divers, launched in French Polynesia in late 2018. Our 16 are a subset of the 50 MERMAID deployed over a number of cruises in this vast and understudied oceanic province as part of the collaborative South Pacific [...]
Cascadia megathrust earthquake rupture model constrained by geodetic fault locking
Published: 2020-11-30
Subjects: Earth Sciences
Paleo-earthquakes along the Cascadia subduction zone inferred from offshore sediments and Japan coastal tsunami deposits approximated to M9+ and ruptured the entire margin. However, due to the lack of modern megathrust earthquake records and generally quiescence of subduction fault seismicity, the potential megathrust rupture scenario and influence of downdip limit of the seismogenic zone are [...]