Preprints
There are 7999 Preprints listed.
Massive High-Fidelity Focal Mechanisms Reveal Detailed Structure of Re-Activated Faults During Hydraulic Fracturing in Western Canada
Published: 2025-09-14
Subjects: Geophysics and Seismology
Microseismic focal mechanism solutions (FMSs) are essential for understanding reservoir stress changes and rock fracturing during hydraulic fracturing. While machine learning has shown strong performance in seismic data processing tasks, including phase picking and magnitude estimation, as well as identifying P-wave first-motion polarity for moderate to large earthquakes to invert FMSs, its [...]
A Hybrid Iron/Green-Rust-Urea Model for Prebiotic Chemistry: A Synthesis of Testable Pathways for Planetary Astrobiology
Published: 2025-09-17
Subjects: Earth Sciences, Geochemistry, Planetary Geochemistry, Planetary Geology, Planetary Hydrology, Planetary Sciences
We propose a quantitative, testable framework for abiogenesis that links submarine alkaline vents, which supply H₂, ΔpH, and Fe/Fe–S catalysis, to subaerial hot-spring fields that provide wet–dry concentration and UV-driven photoredox chemistry. To bridge dilution between environments, we specify mobile “holding pens” (green-rust/iron flocs, silica mats, pumice rafts, and sea-surface [...]
Breaking the Cycle: Short Recurrence and Overshoot of an M9-class Kamchatka Earthquake
Published: 2025-09-18
Subjects: Physical Sciences and Mathematics
M9-class megathrust earthquakes in subduction zones are generally thought to release slip deficits on the plate interface accumulated over centuries. However, the 2025 Kamchatka earthquake (Mw 8.8--8.9) ruptured nearly the same area as the 1952 Mw 9.0 event, as shown by the aftershock distribution. This unusually short recurrence interval challenges conventional seismic-cycle models used for [...]
Adverse Climate: Addressing Inclusion and Diversity Issues in the IPCC's Sixth Assessment and beyond
Published: 2025-09-17
Subjects: Social and Behavioral Sciences
In this essay, we reflect on what it means for the scientific community to collaborate effectively in global scientific assessments, drawing on our experience within the Intergovernmental Panel on Climate Change (IPCC) and with relevance beyond the IPCC to many other scientific collaborations. We amplify IPCC author voices through lived-experience narratives that reveal how systemic barriers [...]
Efficient Self-Attention Based Joint Optimization for Lithology and Petrophysical Parameter Estimation in the Athabasca Oil Sands
Published: 2025-09-17
Subjects: Artificial Intelligence and Robotics, Earth Sciences, Geology, Geophysics and Seismology
Accurately identifying lithology and petrophysical parameters, such as porosity and water saturation, are essential in reservoir characterization. Manual interpretation of well-log data, the conventional approach, is not only labor-intensive but also susceptible to human errors. To address these challenges of lithology identification and petrophysical parameter estimation in the Athabasca Oil [...]
FLOCCULATION, GRAVITY FLOWS, AND TOTAL ORGANIC CARBON HOTSPOTS IN LAKE: INSIGHTS FROM FLUME EXPERIMENTS
Published: 2025-09-17
Subjects: Earth Sciences, Physical Sciences and Mathematics
Lakes serve as one of the significant sinks for organic carbon. For lake deposits, it is generally accepted that water depth is a primary control on the spatial distribution of total organic carbon (TOC) accumulation because the deeper part of a lake potentially has a higher organic population to be settled. However, lake TOC distribution is often spatially variable regardless of water depth, and [...]
Dynamic Reservoir Modeling for Water Security under Climatic and Anthropogenic Pressures in Aburrá Valley
Published: 2025-09-02
Subjects: Civil and Environmental Engineering
Water security in Aburrá Valley, Colombia, relies heavily on the Riogrande II and La Fe reservoirs, which face increasing pressures from climate variability, land use change, and rising demand. Although SWAT+ is a powerful hydrological modeling tool, its reservoir module cannot represent dynamic changes in demand, land use, or external water inflow. To address these limitations, we developed [...]
The Shapes and Sizes of Macroplastics and Other Litter in Rivers
Published: 2025-09-17
Subjects: Engineering, Life Sciences, Physical Sciences and Mathematics
Limited data exists on physical and geometric properties of river litter. To resolve this, we reveal the physical-structural relationships of river litter, using two of the most comprehensive datasets generated to date. First, we dissect the properties of river litter using a detailed dataset of over 14,052 riverbank items, for which their dimensions (longest L₁, intermediate L₂, shortest L₃) and [...]
Support for Forest Conservation Imperatives: A Robust Approach for Multi-dimensional, Spatially Explicit Resilience Assessment
Published: 2025-09-18
Subjects: Environmental Indicators and Impact Assessment, Forest Management, Natural Resources and Conservation, Terrestrial and Aquatic Ecology
Forest ecosystems are ecologically, socially, and culturally valuable, and are arguably considered essential to global sustainability. Climate change and altered disturbance regimes are threatening the future of forests around the globe. Many countries are coming together to support and implement conservation and monitoring initiatives to improve future prospects for the restoration and [...]
Global news reports reveal the human dimensions of water scarcity
Published: 2026-11-05
Subjects: Civil and Environmental Engineering, Engineering
Water scarcity has conventionally been estimated using hydrologic models that quantify pressure on water resources. Yet hydrologic stress does not necessarily translate into water shortages, as human adaptation can buffer physical constraints while infrastructure and institutional failures can create scarcity even where water is abundant. Here, we use large language models to identify news [...]
Disturbance and incomplete recovery in the Cerrado-Amazon transition: Implications for conservation of a critical tropical ecotone
Published: 2025-10-20
Subjects: Geography, Remote Sensing, Social and Behavioral Sciences
The Cerrado-Amazon Transition (CAT) is the world's largest tropical forest–savanna ecotone and a key component of Brazil's “Arc of Deforestation”. It harbours high biodiversity but remains weakly protected and increasingly exposed to agricultural expansion, deforestation, and fire. Using Landsat time series (1986–2020), we developed a disturbance–recovery framework to track how repeated and [...]
Minkowski Functionals as Analytical Predictors of Permeability in Porous Microstructures
Published: 2025-09-19
Subjects: Civil and Environmental Engineering, Engineering, Materials Science and Engineering, Mechanical Engineering
Understanding the relationship between microstructure and macroscopic properties in porous media remains crucial for numerous applications in geoscience and engineering. For example, accurate predictability of permeability is essential for optimizing fluid flow processes in applications such as hydrocarbon recovery, groundwater management, and carbon or energy storage. The Kozeny-Carman equation [...]
Volcanic CO2 degassing and microbial carbon fixation in a caldera offshore
Published: 2026-03-14
Subjects: Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Volcanology
Calderas are subsided volcanic terrains formed by the destructive power of some of the largest volcanic eruptions on Earth. Many such depressions globally are today submerged by crater lakes or seawater, rendering them less accessible to scientific scrutiny, and hence more complicated to monitor during unrest. One of such systems is the restless, partly submerged Campi Flegrei caldera (CFc) near [...]
Machine Learning Generated Streamflow Drought Forecasts for the Conterminous United States (CONUS): Developing and Evaluating an Operational Tool to Enhance Sub-seasonal to Seasonal Streamflow Drought Early Warning for Gaged Locations
Published: 2025-09-19
Subjects: Hydrology, Water Resource Management
Forecasts of streamflow drought, when streamflow declines below typical levels, are notably less available than for floods or meteorological drought, despite widespread impacts. To address this gap, we apply machine learning (ML) models to forecast streamflow drought 1-13 weeks into the future at > 3,000 streamgage locations across the conterminous United States (CONUS). We applied two ML [...]
Unreliable Results of a Commercial Real-Time Water Quality Sensor in Identifying Fecal Contamination of Drinking Water
Published: 2025-09-19
Subjects: Civil and Environmental Engineering
Low-cost technologies are increasingly being explored and marketed as capable of filling gaps in global water quality monitoring (WQM), especially in resource-limited settings. This study evaluates a commercially available, low-cost triboelectric-based sensor that is marketed for real-time detection of E. coli in drinking and environmental waters. A result of 0 indicates contaminated water, [...]