Preprints
Filtering by Subject: Geochemistry
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, [...]
Mineral stability and porosity dynamics in Halite- and Kainite-bearing rocks after hydrogen batch reaction test: a case study of Realmonte mine, Sicily (Italy)
Published: 2026-08-20
Subjects: Earth Sciences, Geochemistry, Geology, Mineral Physics, Mining Engineering, Oil, Gas, and Energy, Risk Analysis, Stratigraphy, Sustainability
Underground hydrogen storage in salt caverns is among the most mature geological storage options, yet the behaviour of potash-salt lithologies under hydrogen exposure remains entirely uncharacterised. This study presents a multi-technique characterisation, performed on selected representative samples, of Messinian halite and kainite-bearing evaporites from the Realmonte mine (Sicily) subjected to [...]
Reconstructing the P-T-t evolution recorded in garnet through growth and multicomponent diffusion modelling
Published: 2026-08-20
Subjects: Earth Sciences, Geochemistry, Geology
Interpreting the P –T evolution of a region recorded in garnet requires understanding of how the major elements in garnet (Fe, Mg, Mn and Ca) are modified by diffusion. We present an integrated approach that combines thermodynamic modelling with MAGEMin and multicomponent diffusion modelling using UWDiffusion, built on underworld3, to constrain the P–T–t evolution of a garnet pyroxenite from the [...]
Fluorapatite Breakdown and Fluor-edenite Formation in the Pristine Winonaite Calate 047 from Chile's Atacama Desert
Published: 2026-08-13
Subjects: Cosmochemistry, Geochemistry, Mineral Physics, Planetary Geochemistry, Planetary Mineral Physics
We report the discovery and characterization of Calate 047, a new amphibole-bearing winonaite found in Chile's Atacama Desert. This meteorite exhibits a fine-grained granoblastic texture with equigranular silicates (70-350 μm) and extremely magnesian compositions (olivine Fa1.6-1.8, low-Ca pyroxene Wo1.46-1.7Fs0.44-1.17, high-Ca pyroxene Wo45.26-45.81Fs0.70-0.93, plagioclase An17.7-18.8). Calate [...]
River dissolved inorganic carbon losses from the Andes to lowland Amazon via cryptic sedimentary exchange processes
Published: 2026-08-05
Subjects: Biogeochemistry, Earth Sciences, Geochemistry, Geomorphology, Hydrology
River carbon transfers and associated greenhouse gas emissions are a major component of the carbon cycle. Proposals to use rivers and their catchments to increase carbon dioxide (CO2) drawdown, by enhanced rock weathering and river alkalinity enhancement, require secure delivery of dissolved inorganic carbon (DIC) and increased cation loads (e.g. Ca2+) to the ocean. Here we explore the fate of [...]
Topology-Preserving Multifractal Exchange Upscaling for Flow and Reactive Transport in Fractured Crystalline Rock
Published: 2026-07-31
Subjects: Geochemistry, Geology
Groundwater flow and radionuclide transport in fractured crystalline rock are governed by multiscale fracture connectivity, heterogeneous hydraulic properties, matrix diffusion, and coupled geochemical processes. Conventional continuum and discrete-fracture models often have difficulty preserving both geometric complexity and transport-relevant connectivity during upscaling. This study presents a [...]
Manganese Oxidation States Reveal a Continental-Scale Climate-Driven Redox Gradient in Upland Soils
Published: 2026-07-29
Subjects: Biochemistry, Geochemistry, Soil Science
Soil redox conditions regulate soil organic carbon (SOC) persistence and nutrient availability, yet macroclimatic controls in uplands remain unclear because O2 depletion reflects the interactions of moisture, labile carbon, soil texture, and microbial demand. Here we pair manganese (Mn) oxidation state, an integrative redox proxy, with effective water balance (mean annual precipitation minus [...]
Rapid SRO aluminosilicate formation in a narrow pH interval fractionates silicon isotopes
Published: 2026-07-27
Subjects: Earth Sciences, Geochemistry, Soil Science
Short-range ordered (SRO) hydrous aluminosilicates (HAS) are among the earliest secondary phases formed during incongruent silicate weathering, yet the timescales and silicon isotope (δ30Si) fractionation associated with their initial formation remains poorly constrained. We use stepwise room temperature NaOH titration to resolve pH buffering, Si–Al removal, and dissolved δ30Si evolution in two [...]