Preprints
There are 5114 Preprints listed.
Rapid transformation of biogenic silica to authigenic clay during reverse weathering
Published: 2024-10-01
Subjects: Earth Sciences, Geochemistry
Formation of authigenic clay minerals during early diagenesis of marine sediments, termed “reverse weathering” (RW), is an important process for regulating ocean pH and atmospheric CO2 over geologic time scales. It is also considered a“missing sink” of the modern marine Si cycle. Although the importance of RW has been increasingly recognized, the rate and mechanisms of this process remain [...]
Comprehensive Assessment of Drought Impact on Crop Yields Across Iowa Over Two Decades (2000-2022)
Published: 2024-09-30
Subjects: Civil and Environmental Engineering, Engineering
Corn and soybeans are pivotal crops in the U.S. agricultural landscape, providing essential vitamins and oils. These two crops dominate approximately 90% of crop production in Iowa. However, their yields are significantly impacted by recurrent drought conditions. A prolonged deficiency in soil moisture characterizes agricultural drought due to sustained precipitation shortfalls. This study aims [...]
Predicting Harmful Algal Blooms Using Explainable Deep Learning Models: A Comparative Study
Published: 2024-09-29
Subjects: Environmental Engineering
Harmful algal blooms (HABs) have emerged as a significant environmental challenge, impacting aquatic ecosystems, drinking water supply systems, and human health due to the combined effects of human activities and climate change. This study investigates the performance of deep learning models, particularly the Transformer model, as there are limited studies exploring its effectiveness in HAB [...]
Landscape evolution of the Black Forest: From the Variscan orogeny to the modern era
Published: 2024-09-28
Subjects: Geomorphology, Glaciology, Soil Science
With a maximum elevation of 1493 m above sea-level, the Black Forest (Schwarzwald in German) is the second highest mountain range in Germany. It is subdivided in three main natural regions, the northern, central, and southern Black Forest. The Variscan basement of the Black Forest consists of plutonic and metamorphic rocks. Sedimentary rocks formed during the Mesozoic under marine and terrestrial [...]
Who talks about climate, peace and security? A social media analysis to identify key actors
Published: 2024-09-28
Subjects: International and Area Studies
Uncovering key actors within a policy network provides pathways for engagement, consensus-building, partnership development, and understanding the diffusion of knowledge in a given debate. Given the unprecedented scale of the climate emergency, the emerging field of climate security has rapidly gained centrality in academic and policy fora, as well as in the public debate. Yet, a systematic [...]
Seismicity-constrained fault detection and characterization with a multitask machine learning model
Published: 2024-09-28
Subjects: Physical Sciences and Mathematics
Geological fault detection and characterization from geophysical data have been one of the center challenges in geophysics and seismology as it holds the key to understanding subsurface dynamics ranging from borehole, reservoir, to regional scales. While paradigms of auto or semi-auto fault delineation either based on seismicity location analysis or on seismic migration image reflector [...]
Unveiling Year-Round Cropland Cover by Soil-Specific Spectral Unmixing of Landsat and Sentinel-2 Time Series
Published: 2024-09-28
Subjects: Agriculture, Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring
Croplands are essential for food security but also impact the environment, biodiversity, and climate. Understanding, monitoring, modeling, and managing these impacts require accurate, comprehensive information on cropland vegetation cover. This study aimed to continuously monitor the state and vegetative processes of cropland, focusing on the assessment of bare soil and its cover with [...]
Improved Precision and Reference Materials for Stable Carbon Isotope Analysis in Basaltic Glasses using Secondary Ion Mass Spectrometry
Published: 2024-09-27
Subjects: Earth Sciences, Geochemistry, Volcanology
We introduce three new reference materials and a new high-precision set-up for stable carbon isotope analysis in basaltic glasses using large-geometry secondary ion mass spectrometry (SIMS) instrument. The new hydrous basaltic reference materials, characterised for carbon concentration and isotope composition by step-heating gas extraction and manometry followed by isotope ratio mass [...]
Assessing the timing of deep ocean oxygenation from uranium elemental and isotopic compositions of ophiolites
Published: 2024-09-26
Subjects: Earth Sciences, Geochemistry, Geology
The concentration of dissolved oxygen in the deep oceans has varied over Earth History, with the timing of the transition from anoxic to oxic deep oceans debated. Under modern-day, oxic, deep ocean conditions, alteration of the upper sections of mafic oceanic crust with U-rich seawater leads to U enrichment, low Th/U ratios, and heterogeneous 238U/235U ratios relative to fresh mid-ocean ridge [...]
Prioritizing Safety, Advancing Efficiency: Developing a New Total Phosphorous Microwave Digestion Method for Sediment Core Nutrient Analysis
Published: 2024-09-26
Subjects: Biogeochemistry, Environmental Chemistry, Inorganic Chemistry, Soil Science
Long-term datasets are invaluable resources for understanding broad-level temporal patterns in ecosystems. For over two decades, UC Davis and Lake County Water Resources Department have collaborated on a long-term monitoring project of Clear Lake sediment nutrient concentrations, in an effort to better understand nutrient cycling in Clear Lake. When the need for a new total phosphorus digestion [...]
Groundwater use to reduce natural hazard susceptibilities and inequities in the metacrisis
Published: 2024-09-26
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics
Long-term thinking is broadly advocated for groundwater - the largest available freshwater resource that is essential for drinking water, irrigation and ecosystems around the world. Long-term thinking is crucial to support sustainability of this slowly renewed resource, but here we propose another crucial, novel and emerging approach for groundwater: short-term use over days and months during or [...]
3D wave propagation and earthquake dynamic rupture simulations in complex poroelastic media
Published: 2024-09-26
Subjects: Geophysics and Seismology
Numerical simulations of earthquakes and seismic wave propagation require accurate material models of the solid Earth. In contrast to purely elastic rheology, poroelasticity accounts for pore fluid pressure and fluid flow in porous media. Poroelastic effects can alter both the seismic wave field and the dynamic rupture characteristics of earthquakes. For example, the presence of fluids may affect [...]
Regional Source-type Discrimination Using Nonlinear Alignment Algorithms
Published: 2024-09-26
Subjects: Physical Sciences and Mathematics
The discrimination problem in seismology aims to accurately classify different underground source types based on local, regional and/or teleseismic observations of ground motion. Typical discriminant approaches are rooted in fundamental, physics-based differences in radiation pattern or wave excitation, which can be frequency dependent and may not make use of the full waveform. In this paper, we [...]
High-resolution geophysical monitoring of moisture accumulation preceding slope movement – a path to improved early warning
Published: 2024-09-25
Subjects: Environmental Monitoring, Geomorphology, Geophysics and Seismology, Hydrology
Slope failures are an ongoing global threat leading to significant numbers of fatalities and infrastructure damage. Landslide impact on communities can be reduced using efficient early warning systems to plan mitigation measures and protect elements at risk. This manuscript presents an innovative geophysical approach to monitoring landslide dynamics, which combines Electrical Resistivity [...]
Normal fault interactions in seismic cycles and the impact of fault network geometry
Published: 2024-09-25
Subjects: Physical Sciences and Mathematics
Understanding the mechanisms behind the characteristics of earthquake cycles on normal faults is challenging due to their long recurrence times. Despite their moderate magnitude, normal faulting earthquakes can produce considerable damage. We investigate the effects of fault network geometry and spacing on the seismic cycle of a system of two normal faults modelled with rate-and-state friction [...]