Preprints
Filtering by Subject: Geochemistry
Lixa v0.1.2: an open-source, image-informed framework for closed-loop design of leaching processes for domestic critical-mineral recovery, from the pore to the plant scale
Published: 2026-10-14
Subjects: Earth Sciences, Engineering, Geochemistry, Hydrology, Mining Engineering, Physical Sciences and Mathematics
Leaching takes a metal out of a rock and into a solution. In the United States, rare earth elements, lithium and scandium occur mostly in rocks where the metal is thinly spread through a porous matrix: weathered clays, coal ash, lithium claystones and bauxite residue. For such rocks the leaching recipe (reagent, concentration, temperature, particle size, liquid-to-solid ratio and contact time) [...]
MELVIS: An open-source web application for computing and modelling the viscosity of volcanic melts
Published: 2026-10-13
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics, Volcanology
The viscosity of volcanic melts governs magma transport, eruption dynamics, and a broad range of magmatic processes, so predicting it as a function of temperature, composition, and dissolved water content is central to physical volcanology. Yet no freely accessible tool integrates global machine-learning predictions, physically motivated viscosity equations, and composition-specific models [...]
X-ray microdiffraction mapping on experimentally synthesized clinopyroxenes
Published: 2026-10-12
Subjects: Earth Sciences, Geochemistry, Geology, Volcanology
Crystallographic parameters serve as fundamental archives of crystallization environments, with pressure generally acting as a key variable governing crystal formation. In magmatic systems, tracking crystallographic and chemical parameters in clinopyroxene is critical for robust magmatic thermobarometry and reconstructing crystal life histories. While chemical thermobarometry is limited by melt [...]
Drilled petit-spot basalts reveal asthenospheric mantle heterogeneity before subduction
Published: 2026-10-09
Subjects: Geochemistry, Geology
Submarine petit-spot volcanoes form where oceanic plates bend and flex before sinking into subduction zones, providing a rare opportunity to sample mantle-derived melts before subduction. Here we report results from the first scientific drilling of a sediment-buried petit-spot volcano during International Ocean Drilling Programme Expedition 502, recovering basalts from a previously inaccessible [...]
When and why does CO2 mineralization in basalts stall? A critical review of microscale passivation, pore-clogging mechanisms and the multiscale imaging needed to resolve them
Published: 2026-10-08
Subjects: Geochemistry, Geology
In-situ CO2 mineralization in basalts is among the most secure forms of geological carbon storage. Field pilots report rapid mineralization and, where monitored, stable injectivity, yet many laboratory experiments show that carbonation slows or stops long before the reactive cation inventory of the rock is consumed. We synthesise four field pilots (CarbFix1, CarbFix2, Wallula, Jizan) and 37 [...]
Bulk iron-sulfur ratio (Fe/S) conditional proxy for sulfurized, TOC-rich sediments: insights and comparison of compositional model with real data utilizing the Pyrite-TOC-Fe-S compositional space
Published: 2026-10-04
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics
Bulk iron-sulfur (Fe/S) ratio can be a proxy for sulfurized organic matter in organic-rich shales, particularly those prone to be siliceous or carbonate. First part uses a theoretical model of a compositional system consisting solely of iron, sulfur, TOC, and pyrite to demonstrate how the Fe/S ratio can indicate the presence of sulfurized organic matter using the model’s assumption of sulfur [...]
Model-Based Assessment of Geogenic Radon Exposure in Chaco Canyon and Adjacent Ancestral Puebloan Residential Settings
Published: 2026-09-29
Subjects: Environmental Chemistry, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Public Health, Geochemistry, Other Earth Sciences, Other Environmental Sciences, Other Physics, Paleontology, Sustainability
Naturally occurring radon-222 and its short-lived alpha-emitting progeny are important sources of environmental radioactivity in enclosed, earth-contact spaces, yet their potential relevance to archaeological built environments has rarely been quantified. Here we evaluate chronic radon exposure in Chaco Canyon, where Ancestral Pueblo people occupied earth-contact and semi-subterranean rooms [...]
P-T-t-d history of the Greater Himalayan Sequence in the Zanskar Shear Zone, NW India
Published: 2026-09-23
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Tectonics and Structure
We present a synthesis of pressure-temperature-time-deformation (P-T-t-d) conditions that track the evolution of the Greater Himalaya Sequence (GHS) exhumed along the Zanskar Shear Zone (ZSZ), the western arm of the South Tibetan Detachment and that spans the entirety of the Himalayan range. The dominant mineralogy is Qz + Kfs + Pl + Bt + Grt + Ilm + Sil(Fi) ± Ms ± Ky ± St. P-T paths constructed [...]
Hydrogeochemical Vectoring to Concealed Porphyry Copper Systems Using Unsupervised Machine Learning: A Case Study from Central British Columbia, Canada
Published: 2026-09-23
Subjects: Geochemistry, Geology, Numerical Analysis and Scientific Computing
Environments with thick cover present a challenge to surficial exploration efforts the Canadian Cordillera has extensive Quaternary glacial till and sediment cover, making it difficult to find hidden ore bodies. An alternative is using hydrogeochemistry as an exploration tool, to detect anomalies associated with mineralization. This study demonstrates the hydrogeochemical vectoring to [...]
Mineral-specific ligand and redox dynamics of adsorbed platinum: Pathway-dependent mobility during terrestrial weathering
Published: 2026-09-17
Subjects: Geochemistry
Weathering zones developed above ultramafic rocks, such as oxidized ores, soils, and laterites, concentrate the critical mineral platinum and represent a promising future resource. Prior work has documented Pt accumulation in these zones, including its common association with iron oxides. However, the fundamental mechanisms that control Pt retention versus mobilization during weathering are not [...]
Decoupling Kinetic and Hydrological Controls on Global Silicate Weathering via a Stratified Observational Factorial Framework
Published: 2026-09-17
Subjects: Design of Experiments and Sample Surveys, Geochemistry
Continental silicate weathering acts as the primary geological sink for atmosphericcarbon dioxide over multimillion-year timescales, yet whether weathering fluxes arefundamentally governed by thermodynamic temperature limits or hydrological runoffremains fiercely debated. Resolving this controversy globally has been hindered by thestrong natural collinearity of terrestrial temperature and [...]
Global isotopic proxy records for Ordovician temperature reconstruction
Published: 2026-09-16
Subjects: Earth Sciences, Geochemistry, Geology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
The Ordovician represents a critical interval in the Phanerozoic, marked by two profound biological events: the Great Ordovician Biodiversification Event (GOBE), with an unprecedented tenfold increase in marine species diversity, which was abruptly terminated by the Late Ordovician Mass Extinction (LOME), one of the most severe extinction events in Earth's history, wiping out approximately 85% of [...]
Phanerozoic atmosphere and ocean conditions estimated by a continuous climate and multi-box ocean model
Published: 2026-09-15
Subjects: Biogeochemistry, Geochemistry, Other Earth Sciences
The Phanerozoic Eon has witnessed marked fluctuations in Earth’s climate and the concentrations of elements conducive to life. Understanding what has driven these changes to the Earth system over such a long timeframe has traditionally used ‘box models’ which split the Earth into a small number of chemical reservoirs, with many models utilising a single, combined ocean-atmosphere reservoir. This [...]
Revisiting the felsőbányaite-basaluminite question : nomenclatural synonymy and unresolved structural issues
Published: 2026-09-09
Subjects: Earth Sciences, Geochemistry, Mineral Physics, Soil Science
Felsőbányaite (1853) and basaluminite (1948) share the formula Al4(SO4)(OH)10·4H2O, and were shown to be crystallographically identical in 1997, leading the IMA to discredit basaluminite in 2006 in favor of the older name. This nomenclatural choice is not an issue. Instead, this opinion article explores a more focused contemporary question: is the poorly crystalline material that geochemists [...]
Silicate Weathering Dynamics in the Kasaï Basin and Implications for Enhanced Rock Weathering Applications in the Tropics
Published: 2026-08-25
Subjects: Earth Sciences, Geochemistry, Physical Sciences and Mathematics
Silicate weathering is one of the ultimate geologic sinks of atmospheric CO2. Enhanced rock weathering (ERW), aiming at accelerating this natural process to mitigate anthropogenic warming, has received significant attention due to high projected CO2 removal potential and possible agricultural co-benefits applications in the tropics. Yet, the natural baseline of chemical weathering in low-relief, [...]