Preprints
There are 8003 Preprints listed.
Forward-testing mineral prospectivity models with discovery dates: Quebec graphite and nickel
Published: 2026-10-27
Subjects: Geology, Mining Engineering
Mineral prospectivity models are usually evaluated with spatial cross-validation, but known occurrences cluster around past exploration, so this may measure performance within the explored footprint rather than the ability to rank later discoveries. We trained seven prospectivity models on graphite and nickel occurrences known in Quebec, Canada, before 2000 and tested how they ranked cells with [...]
Apatite inclusions in zircon reveal a crustal origin for HREE depletion in Archean granitoids
Published: 2026-10-29
Subjects: Physical Sciences and Mathematics
Reconstructing the geodynamic conditions of the Hadean and Archean is essential for understanding Earth’s evolution and the conditions that ultimately enabled life to emerge. Archean tonalite–trondhjemite–granodiorite (TTG) suites have been studied extensively because their evolved compositions provide clues to the processes that formed the early continental crust. Their trace-element signatures, [...]
Development and validation of a field-compatible workflow for molecular diagnostics of microbial water quality
Published: 2026-11-03
Subjects: Microbiology
Molecular diagnostics provide advantages in many areas of water quality analysis compared to cultivation-based methods, yet their implementation remains limited mainly due to reliance on specialized instruments, trained personnel and regulatory barriers. To bridge this gap, we developed and evaluated a rapid and field-compatible workflow for the assessment of microbiological water quality. The [...]
Structure Function Sampling Uncertainty: A Gaussian-Increment Reference Framework
Published: 2026-10-28
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology
Structure functions (SFs) are widely used to characterize scale-dependent variability in geophysical fields, but their sampling uncertainty is difficult to quantify because pairwise increments are generally dependent. Dependence arises from both shared observations and spatial covariance of the underlying field, so pair counts alone do not determine uncertainty. The sampling variance is governed [...]
Triple oxygen isotope equilibrium between calcite and water: new constraints over 8–200 °C and their metrological implications
Published: 2026-10-28
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
High-precision measurements of carbonate oxygen-17 compositions are increasingly used for studying paleo-environments, hydrology, diagenesis, or biomineralization processes. Calibrating triple oxygen isotope equilibrium fractionations between calcite and water as a function of temperature provides a critical baseline for many applications. Here we report new observations constraining these [...]
Droughts are dominated by anomalous circulation not anomalous atmospheric moisture content
Published: 2026-10-29
Subjects: Atmospheric Sciences, Climate
Agricultural drought is a sustained soil moisture deficit caused by reduced net moisture flux to the land surface. We show that agricultural droughts can occur when the atmosphere is anomalously wet, challenging the assumption that surface drying reflects atmospheric moisture deficits. Precipitation declines during drought even under increased atmospheric moisture, indicating low precipitation [...]
Geological concept revision during appraisal drilling: a replay of the McLeod VMS deposit, Matagami
Published: 2026-11-04
Subjects: Physical Sciences and Mathematics
Appraisal drilling is designed around a geological concept, yet discovery records show that such concepts are often partly wrong and revised late. We propose a procedure that updates the geological concept during drilling and quantifies the cost of delayed revision. The concept is written as a lattice of geological elements, each present or absent with a prior weight, so that revision becomes [...]
A domain-specific atomistic model for Earth’s core materials
Published: 2026-11-04
Subjects: Earth Sciences, Mineral Physics
Understanding Earth’s core requires accurate descriptions of multicomponent iron alloys under extreme conditions. Here, we develop the Earth’s Core Atomistic Model (ECAM) for Fe–Ni–S–Si–O–C–H alloys through sampling with a foundational atomistic model, targeted ab initio simulations, and iterative exploration. A compact dataset selected from nearly half a million configurations is consistently [...]
Repeatability-dependent detection thresholds for time-lapse seismic CO₂ monitoring
Published: 2026-11-03
Subjects: Geophysics and Seismology
We quantify the smallest CO₂ layer that a time-lapse seismic survey pair can detect as a function of repeatability, measured by the normalized root-mean-square (NRMS) difference, in a Sleipner-like synthetic study. Gassmann fluid substitution under four mixing treatments feeds one-dimensional layer models, checked against two-dimensional finite-difference gathers, and calibrated nonrepeatability [...]
Hotspots of Efficient Large-scale Circulation Response to Idealized Diabatic Heating
Published: 2026-10-30
Subjects: Atmospheric Sciences, Climate
Soil moisture anomalies can influence large-scale atmospheric circulation and thereby affect remote regions. However, the seasonal and geographical dependence of these circulation responses has been largely unexplored. Here, we conduct idealized experiments with a Linear Baroclinic Model, imposing identical low-level diabatic heating anomalies across global land to examine atmospheric circulation [...]
Where the Water Begins: A Field Guide to Six Streams Rising in the Knuckles Mountain Range, Sri Lanka
Published: 2026-10-30
Subjects: Hydrology, Physical and Environmental Geography, Water Resource Management
The Knuckles mountain range in central Sri Lanka is one of the wettest parts of the Mahaweli basin, and the streams that rise on its slopes feed the Victoria, Randenigala, Moragahakanda and Kalu Ganga reservoirs on which irrigation, hydropower and drinking water for a large part of the country depend. Walkers in the range meet these streams every day, yet there is no single account of where each [...]
Typhoons reseal mountain groundwater systems after earthquake damage
Published: 2026-09-04
Subjects: Physical Sciences and Mathematics
Bedrock groundwater supplies water services to half the global population. Earthquakes can disrupt this resource for years by changing subsurface permeability. Several mechanisms have been proposed for these changes, but their influence remains debated, because hydrological observations alone cannot distinguish them. We combine groundwater-derived permeability with seismic wavespeed, a measure of [...]
Simulated heatwave increases CO₂ efflux from unvegetated saltpans and amplifies CH₄ efflux from vegetated saltmarshes
Published: 2026-11-04
Subjects: Terrestrial and Aquatic Ecology
Atmospheric heatwaves are increasing in frequency, intensity and duration under anthropogenic climate change, yet their effects on greenhouse gas (GHG) fluxes from coastal wetlands remain poorly understood. Coastal wetlands, including saltmarshes and saltpans (also called salt flat and sabkha), are globally significant carbon stores, but their vulnerability to extreme heat has rarely been tested [...]
Characterising Methane Concentration Variability at Coal Stockpiles in a Surface Coal Mine
Published: 2026-10-29
Subjects: Engineering, Physical Sciences and Mathematics
The spatiotemporal variability of atmospheric methane concentration at surface coal mines remains insufficiently characterised. The impact of local meteorology and mining activities on methane emission have not yet been fully evaluated. In this study, ground observations of the methane concentration along with meteorology were carried out around coal stockpiles (CSP) in an active surface coal [...]
Post-processing Subglacial Physics Model with Per-site JEPA Specialist Models Enable Natural-language Glaciological Intelligence
Published: 2026-10-29
Subjects: Physical Sciences and Mathematics
Glaciers slide over their beds, and how fast they slide depends on the pressure of meltwater trapped beneath them. This subglacial environment is nearly impossible to observe directly and is one of the largest uncertainties in how fast glaciers lose ice and how much water they deliver to communities downstream. Ice-sheet models represent it with empirical rules that are hard to test, and although [...]