Preprints
Filtering by Subject: Geology
From rifting to collision: deep closure of a Wilson cycle during the Archean–Paleoproterozoic transition at the Carajás-Bacajá boundary, Amazonian Craton
Published: 2026-10-21
Subjects: Earth Sciences, Geochemistry, Geology, Tectonics and Structure
The Carajás-Bacajá boundary preserves complementary archives of continental rifting, passive-margin development, subduction, collision and post-collisional exhumation across the Archean-Paleoproterozoic transition. We present whole-rock lithogeochemistry, Sm-Nd isotopes, U-Pb zircon geochronology and thermobarometry from the Vila Santa Fé-Rio Preto association, a mafic-felsic granulitic [...]
Decoupling ore formation, ductile fabric and hydrothermal upgrading in the giant Salobo IOCG deposit, Carajás Province, Brazil
Published: 2026-10-21
Subjects: Earth Sciences, Geochemistry, Geology, Tectonics and Structure
The Salobo deposit is the largest Cu-Au deposit of the Carajás Mineral Province, northern Brazil, and is hosted by altered volcanosedimentary schists of the Itacaiúnas Supergroup along the Cinzento Lineament. Multiscale structural analysis, mineral chemistry and published geochronology define four structural families: Pre-Dn, Dn, Dn+1 and Dn+2. The Pre-Dn event comprises high-temperature K, K-Fe [...]
MCR-GeoChem: Aharmonized, quality-flagged open compilation of whole-rock and mineral geochemistry for the 1.1 Ga Midcontinent Rift in Michigan, Minnesota, and Wisconsin
Published: 2026-10-21
Subjects: Earth Sciences, Education, Environmental Sciences, Geochemistry, Geology, Higher Education, Physical Sciences and Mathematics
Nickel, copper, cobalt, and the platinum-group metals are all on the final 2025 U.S. List of Critical Minerals, and the 1.1-billion-year-old Midcontinent Rift around Lake Superior hosts some of the largest domestic resources of them. The rock chemistry needed to study these systems is public but fragmented: it is spread across the U.S. Geological Survey (USGS) National Geochemical Database, [...]
3D inversions of magnetic and gravity data for the Yaouré region, Ivory Coast: a greenstone belt characterization
Published: 2026-10-21
Subjects: Earth Sciences, Geology, Geophysics and Seismology
We carried out 3D inverse modeling of full tensor gravity gradiometry data, its derived products (Tz and Tz residual), and magnetic data to recover the density and magnetic susceptibility distributions of the Yaouré Greenstone Belt in Ivory Coast, West Africa. The study area presents significant challenges: it lacks well-defined stratigraphy and structural measurements, and it lies close to the [...]
Earth's Bad Decades: A Sedimentary Record of the Chicxulub Aftermath from the New Jersey Coastal Plain and Offshore
Published: 2026-10-16
Subjects: Earth Sciences, Geochemistry, Geology, Geophysics and Seismology, Sedimentology, Stratigraphy
The New Jersey Coastal Plain (NJCP) preserves records of the Chicxulub impact approximately 2,500 km from the crater, providing a unique archive of ejecta fallout, sediment reworking, ecological disruption, and recovery following the end-Cretaceous mass extinction. Preservation of impact deposits varies with depositional setting. Offshore sections beneath the NJ continental shelf and slope [...]
Characteristics and consequences of H2O undersaturation and low melt fertility in mountain belt interiors
Published: 2026-10-15
Subjects: Earth Sciences, Geology, Tectonics and Structure
Continental deformation and crustal magmatism in orogenic settings are fundamentally linked to fluid availability and melting processes. Critical rheological transitions occur at approximately 7% melt volume, whereby melt-film connectivity reduces rock strength by as much as c. 90%, and at 20%, marking an onset of solid-to-liquid behaviour. The Mesoproterozoic Grenville orogen in Canada provides [...]
Active hazardous slow faults drive drainage evolution in the Atacama Desert
Published: 2026-10-14
Subjects: Earth Sciences, Geology, Geomorphology, Hydrology, Tectonics and Structure
The Atacama Desert of the Central Andean forearc is the driest non-polar region on Earth, where extremely low erosion rates preserve geomorphic markers over Myr timescales. Between 19°S and 20°S, subtle Quaternary east-vergent reverse faults deform the west-sloping landscape and disrupt drainage development. This setting provides a unique opportunity to investigate fault evolution, uplift [...]
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 [...]
The critical role of stored energy in metamorphism
Published: 2026-10-09
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics
The mechanical behaviour of the Earth is widely assumed to change with increasing timescale as rocks progressively relax imposed stresses [1]. On short timescales, elasticity dominates and its release drives earthquakes [2]; at intermediate timescales, viscoelastic relaxation facilitates processes such as glacial rebound [3]; whereas over geological timescales viscous deformation dominates, [...]
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 [...]
Understanding Earthquake Physics with On-Fault Observatories
Published: 2026-10-02
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
Earthquakes often strike without warning. Current fault monitoring infrastructure is not sensitive enough to detect signals such as accelerating fault creep or dilation, which laboratory experiments and numerical models predict may precede large earthquakes. Here we argue that a paradigm shift is needed and technically achievable: from inferring faulting processes from a distance with surface [...]
Leveraging Ocean Data and Models: Building the Data Infrastructure, Workforce, and Modeling Capacity to Synthesize Earth’s Ocean Observations
Published: 2026-09-25
Subjects: Artificial Intelligence and Robotics, Atmospheric Sciences, Biogeochemistry, Climate, Computer Sciences, Databases and Information Systems, Earth Sciences, Environmental Sciences, Fresh Water Studies, Geology, Hydrology, Meteorology, Numerical Analysis and Scientific Computing, Oceanography, Other Earth Sciences, Other Oceanography and Atmospheric Sciences and Meteorology
NASA’s aquatic and marine research enterprise within the overarching NASA Biosphere Program is entering an era of unprecedented data abundance. MODIS and the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission already generate ocean color data at rates that strain legacy processing and archiving workflows, and forthcoming missions will add further volume and complexity. These satellite [...]
Deep seismo-volcanic tremors constrain the magma supply from the mantle
Published: 2026-09-24
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics, Volcanology
Volcanic eruptions are driven by magma supplied from the mantle, yet deep magmatic flux remains poorly constrained. Here we propose to quantify it based on deep seismic tremors. We adopt a model of tremor generation by rapid growth of gas bubbles in response to magma decompression and establish a physical relationship between the cumulative seismic moment and the volume of the ascending magma. By [...]