Preprints
Filtering by Subject: Physical Sciences and Mathematics
Detecting rapid lateral changes of upper mantle discontinuities using azimuth-dependent P-wave receiver functions and multimode surface waves
Published: 2025-03-06
Subjects: Physical Sciences and Mathematics
Lateral structural variations in the upper mantle generate azimuthal dependence in receiver functions (RFs) based on incoming directions of body waves. Although these azimuthal variations in RFs have not been considered in earlier studies of RF inversions, they provide a means to image localized changes in upper mantle interfaces. In this study, we incorporate azimuth-dependent RFs into a joint [...]
Velocity of climate change and the vulnerability of mountain lake landscapes
Published: 2025-03-05
Subjects: Life Sciences, Physical Sciences and Mathematics
Freshwater ecosystems in mountain landscapes are increasingly threatened by climate change. Accumulated heat in ecosystems can result in lethal short-term heat exposure, while the velocity of change governs severity and rates of long-term heat exposure. Here, we novelly integrate heat accumulation and velocity of change approaches to classify climate-vulnerable USA mountain lake watersheds. Our [...]
Generative Data Assimilation for Surface Ocean State Estimation from Multi-Modal Satellite Observations
Published: 2025-03-05
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Estimating the surface ocean state at mesoscale eddy-resolving scales is essential for understanding the role of eddies in climate and marine ecosystems. Satellites provide multi-modal observations through sea surface height, temperature (SST), and salinity (SSS). However, each variable is observed with varying resolutions and sparsity, while some variables, such as surface currents, are not yet [...]
Reduced Precipitation on Rapa Nui During the Decline of the Moai Culture
Published: 2025-03-04
Subjects: Atmospheric Sciences, Climate, Environmental Sciences, Environmental Studies, Geography, Human Geography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
From approximately 1200-1600 CE, Polynesian settlers on the island of Rapa Nui engaged in megalithic monument construction, crafting hundreds of Ahu platforms and Moai statues from volcanic bedrock. The decline of this tradition has intrigued archaeologists for decades. The most widely disseminated hypothesis surrounding the demise of the Ahu Moai culture suggests that the Rapanui overexploited [...]
Challenges and Opportunities in Cryosphere in the Hindu Kush Himalaya
Published: 2025-03-04
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Physical Sciences and Mathematics
The Hindu Kush Himalaya cryosphere faces critical challenges from climate change, including rapid glacier melt and reduced snow cover. These changes threaten water resources, ecosystems, and livelihoods across the region. However, opportunities emerge through advanced monitoring technologies and increased scientific understanding. Improved remote sensing and field observations allow better [...]
Conduit dynamics of the Rungwe Pumice eruption (Tanzania): From storage to fragmentation of phonolitic-trachytic magmas
Published: 2025-03-04
Subjects: Physical Sciences and Mathematics
The eruptive style and explosivity of a rising magma are initially shaped by the conditions established in the magmatic plumbing system. However, processes in the conduit during ascent exert a large influence on the final eruption style. Peralkaline magmas—bearing an agpaitic index>1—typically have high water saturation levels, promoting explosive behaviour during ascent. At the same time, [...]
Late Ordovician regional high-pressure metamorphism in Scotland: Caledonian metamorphic climax predated the closure of Iapetus
Published: 2025-03-03
Subjects: Physical Sciences and Mathematics
We document newly recognised Late Ordovician high-pressure (HP) metamorphism in the Scottish Caledonides. Garnet growth at ca. 455–445 Ma within metabasic rocks from the Ross of Mull is constrained to pressures >0.9 GPa and was associated with formation of kyanite-bearing assemblages in meta-pelites that equilibrated at peak conditions of 1.0–1.2 GPa and 700–780°C. This requires the burial of [...]
Performance and Stability Analysis of a GEIOS Proprietary Ionic Nanofluid for Medium to High-Temperature Geothermal Applications
Published: 2025-03-03
Subjects: Chemical Engineering, Engineering, Engineering Science and Materials, Environmental Sciences, Mechanical Engineering, Other Engineering, Physical Sciences and Mathematics, Physics
This study investigates the performance and stability of a proprietary ionic nanofluid developed by GEIOS Technologies for medium to high-temperature geothermal applications. The nanofluid integrates boron nitride nanoparticles, proprietary surface modifiers, and quantum-optimized additives to enhance thermal conductivity, heat transfer efficiency, and operational stability in closed-loop [...]
Novel Nitrogen Hybrid Gas-Based Nanofoam System for Enhanced Geothermal Applications: Nanogeios and GEIOS Geothermal EQG
Published: 2025-03-03
Subjects: Chemical Engineering, Engineering, Materials Science and Engineering, Physical Sciences and Mathematics, Physics
This study presents a novel nitrogen hybrid gas nanofoam system designed for enhanced geothermal applications, validated through comprehensive laboratory testing. The system integrates a nitrogen gas matrix (95% by volume) infused with engineered aluminum oxide (0.6–0.8% vol) and silica (0.3–0.5% vol) nanoparticles, achieving superior thermal conductivity and fracture stability under simulated [...]
Geometric forward modeling of thrust systems underlying shortening landforms on Mercury
Published: 2025-02-28
Subjects: Physical Sciences and Mathematics
Mercury hosts thousands of shortening landforms that are widespread across the entire planet. The shortening is widely accepted to be caused by a combination of thrust faulting and folding, resulting from the global contraction of Mercury caused by long, sustained cooling. Most shortening landforms on Mercury’s surface have been classified into one of two groups: lobate scarps or wrinkle ridges. [...]
Neoproterozoic denudation of a Laurentian superbasin
Published: 2025-02-28
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Tectonics and Structure
It has long been speculated that isolated Paleoproterozoic basins of northern Laurentia are remnants of a once contiguous sedimentary cover due to similarities in stratigraphy, paleocurrent directions, sediment provenance, and geochronological data. However, corroborating evidence for this 'superbasin hypothesis' has been lacking outside the footprints of the preserved basins. We present new [...]
Landscapes on the edge: river intermittency in a warming world
Published: 2025-02-28
Subjects: Physical Sciences and Mathematics
Sediment transport in rivers is not uniform through time. Highly intermittent systems, which only transport bedload during the most significant flow events, are particularly sensitive to changes in climate and precipitation patterns. Quantifying river intermittency is critical for assessing how fluvial landscapes will respond to projected changes in precipitation extremes due to climate change, [...]
Patterns of deformation in the deepest mantle linked to ancient subduction
Published: 2025-02-25
Subjects: Physical Sciences and Mathematics
Shear wave speeds in Earth's deepest mantle (D") that vary with wave propagation and polarization direction -- a property called seismic anisotropy -- offer insights into mantle convection. To date, global patterns of D" anisotropy have been mostly derived from long wavelength radially anisotropic tomography models, which often disagree except for the large-scale degree-2 pattern. Here, we [...]
Trends and ENSO-related variability in Atlantic tropical cyclone intensity and intensification
Published: 2025-02-23
Subjects: Physical Sciences and Mathematics
This study examined trends and ENSO-related variability in Atlantic tropical cyclone intensity, focusing on 24-h intensification, lifetime maximum intensity (LMI), and rapid intensification (RI) in best-track data during the period 1982–2024. Previous studies considered trends and ENSO influences separately, reporting upward trends in intensity and more cases of RI during La Niña conditions. [...]
Thirty Years of the Open Geospatial Consortium - History, Present, and Future
Published: 2025-02-23
Subjects: Engineering, Physical Sciences and Mathematics, Social and Behavioral Sciences
For 30 years, the Open Geospatial Consortium (OGC) has advanced geospatial interoperability through continuous innovation. The OGC provides strategies and Standards that promote adoption, increase efficiencies, create new opportunities, and transform our relationship with the dynamic planet we inhabit. It has fostered global collaborations among companies, governments, academic institutions, and [...]