Preprints
Filtering by Subject: Earth Sciences
Lithologic Period Predicts Yttrium Enrichment in Western United States Stream Sediments
Published: 2026-11-02
Subjects: Applied Statistics, Design of Experiments and Sample Surveys, Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Statistical Methodology, Statistical Models, Statistics and Probability
Screening ground for heavy rare earth prospecting potential at regional scale depends upon archived geochemistry, because favorable intrusive terrain in the western U.S. greatly exceeds what any drilling program could evaluate directly. This research examined whether the lithologic period of intrusive igneous terrain can reliably predict acid-leachable yttrium using only the stream sediment [...]
A sixth-century groundwater manual tested against India's well network: plant indicators and depth claims in Varāhamihira's Bṛhatsaṃhitā
Published: 2026-11-01
Subjects: Earth Sciences, Hydrology, Life Sciences, Physical Sciences and Mathematics
The Dakārgala chapter of Varāhamihira's Bṛhatsaṃhitā (sixth century CE) is one of the oldest detailed manuals for finding groundwater. It names trees, often together with anthills, as signs of water and gives the depth at which water will be found. It is often cited as early hydrological knowledge, but its claims have not been tested systematically. We coded the chapter's plant indicators and 48 [...]
Climate Risk Intelligence Index (CRII): An AI-Augmented Satellite-Based Climate Vulnerability Assessment Framework for India
Published: 2026-10-30
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Monitoring
Climate change has emerged as a major global challenge affecting environmental sustainability, hydrological stability, urban resilience, and ecosystem health. Conventional climate vulnerability assessment systems primarily rely on static rule-based frameworks and isolated environmental indicators, limiting contextual interpretability and adaptive reasoning across geographically diverse regions. [...]
High-resolution 14C stratigraphy reveals decadal periodicity in stromatolite lamination
Published: 2026-10-30
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Stromatolites constitute amongst the oldest evidence for life on Earth and preserve laminated records throughout most of geological time. However, the timescales represented by their lamination remain poorly constrained. Here, we report the first high-resolution 14C dating combined with Bayesian age-depth modelling for three Holocene stromatolites from contrasting depositional environments. The [...]
Brazil’s climate targets impaired by the potential cessation of the Amazon carbon sink
Published: 2026-10-30
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Environmental Studies, Forest Sciences, Life Sciences, Other Earth Sciences, Sustainability
In accordance with the recommendations of the Intergovernmental Panel on Climate Change (IPCC), countries utilize the "managed land" proxy for their national greenhouse gas (GHG) emission inventories. This implies deducting “passive” carbon removals from countrywide gross GHG emissions. Long-term forest plots indicate that the carbon sink in structurally intact Amazon forest has weakened by [...]
Prospectivity model for magmatic Nickel, Copper, Cobalt, and Platinum-Group Elements in the Midcontinent Rift
Published: 2026-10-30
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Volcanology
Much of the Midcontinent Rift is concealed beneath glacial sediment, which limits direct geological observation and makes it difficult to evaluate the potential for undiscovered magmatic Ni–Cu–PGE deposits with publicly available data. The 1.1 Ga rift hosts the Eagle Ni–Cu–PGE deposit of northern Michigan, one of the few domestic sources of nickel, a critical mineral of the United States. We [...]
Dehydration of Serpentinized Ultramafic Rocks as a Candidate Deep Crustal Source of Natural Hydrogen and Hydrocarbons: Experimental Evidence from the Lesser Caucasus
Published: 2026-10-29
Subjects: Earth Sciences, Geology, Geophysics and Seismology
Natural hydrogen generated by serpentinization — the hydration of ultramafic rocks, in which ferrous iron is oxidised and molecular hydrogen is liberated from water — has recently been shown to proceed at rates of only 0.1 to 0.5 tonnes H₂ yr⁻¹ km⁻³ of reactive rock, implying that economically significant accumulations would require 10³ to 10⁴ years to develop [1]. A complementary process [...]
Late Paleocene leaf macroflora from a destroyed outcrop of the Marcelina Formation, Paso Diablo Mine, Venezuela: a rescue record
Published: 2026-10-29
Subjects: Earth Sciences, Geology, Other Plant Sciences, Paleobiology, Paleontology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
In 2016, a production blast at a mining face of the Paso Diablo Mine (Guasare Basin, northwestern Venezuela) exposed a level rich in fossil leaves of the Marcelina Formation (late Paleocene), located between coal seams 4O and 4M. The material was removed as overburden by a mining shovel a few hours after it was documented. We present the first published record of leaf macroflora from this [...]
Protracted Dyking of High-Viscosity Magma into Near-Solidus Rock at Casiri, Peru
Published: 2026-10-29
Subjects: Earth Sciences, Physical Sciences and Mathematics
Dykes are a key mechanism for material transport within volcanic arcs and typically propagate over days to months. We document an unusually slow dyking episode in the arc of southern Peru that lasted for 1.5 years. The dyke opened up to 0.5 m from 2-8 km depth and was coupled with inflation of an underlying arc-parallel magma reservoir. To reconcile the slow opening of such a thin dyke with [...]
Triple oxygen isotope equilibrium between calcite and water: new constraints over 8–200 °C and their metrological implications
Published: 2026-10-29
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 [...]
Laboratory Spectroradiometric Temperature Retrieval of Silicates Using Linearized Wien Approximations and Polynomial Regression
Published: 2026-10-27
Subjects: Earth Sciences, Geochemistry, Geophysics and Seismology, Mineral Physics
Thermal infrared (TIR) remote sensing provides critical diagnostic capabilities for surface temperature and spectral emissivity retrieval. However, extracting these parameters from at-target radiance measurements is fundamentally ill-posed because Planck's radiation law non-linearly couples kinetic temperature and spectral emissivity, creating an underdetermined system of N spectral bands with [...]
Erosion-induced momentum production and system acceleration govern landslide mobility
Published: 2026-10-26
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Geology, Geomorphology, Geotechnical Engineering, Glaciology, Hydraulic Engineering, Hydrology, Physical Sciences and Mathematics, Risk Analysis, Sedimentology, Social and Behavioral Sciences
Erosion can fundamentally alter landslide acceleration through the produced momentum. However, existing analytical landslide velocity models do not account for the energy dissipation associated with erosion-induced system acceleration. Here, I present a novel, complete dynamical velocity model for erosive landslides that incorporates two intrinsically coupled mechanically essential processes: [...]
Contour-crossing calculations quantify decadal changes in the pCO2 impacts of inorganic chemical weathering in the North American Arctic
Published: 2026-10-26
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Hydrology, Physical Sciences and Mathematics
Degradation of Arctic permafrost is altering biogeochemical dynamics by exposing previously frozen sediment to water, acids, and oxidants. While thaw-driven enhancement of carbonate and silicate mineral weathering results in drawdown of atmospheric carbon dioxide (pCO2), acting as a negative feedback on modern climate change, enhancement of sulfide mineral oxidation increases pCO2 and acts as a [...]
Data-efficient prediction of rare earth leaching from industrial residues with physics-constrained machine learning
Published: 2026-10-25
Subjects: Earth Sciences, Engineering, Geochemistry, Mining Engineering, Physical Sciences and Mathematics
Coal ash, mine-water sludge, red mud and phosphogypsum contain rare earth elements, and each new feedstock needs its own leaching recipe. LixaLearn couples a small neural network to closed-form rate laws for four metal hosts (exchange sites, fast-dissolving minerals, slow-dissolving minerals and a locked fraction), with part of the fast host limited by the solubility of its mineral. The network [...]
Assessing Basin Amplification and Rupture Directivity Effects Using Physics-Based Ground Motion Simulations in Wellington
Published: 2026-10-24
Subjects: Earth Sciences, Geophysics and Seismology
Near-surface velocity structure plays a crucial role in modulating ground motion, and, in turn, contributes to seismic risk. However, a complete understanding of the basin effect is limited, owing to the paucity of detailed shallow basin structure, geological structures and near-field seismic sources. In this study, we perform physics-based simulations of ground motions incorporating the [...]