Preprints
There are 7999 Preprints listed.
Identifying potential hotspots of land use/land cover change in the last 3 decades, Uttarakhand, NW Himalaya
Published: 2022-07-05
Subjects: Physical Sciences and Mathematics
Uttarakhand region in the NW Himalaya has experienced two extreme climatic-geomorphic events within last 10 years that killed more than 6000 people. Though these events, like many others in the Himalaya, have been attributed to climate-change and anthropogenic disturbances, identification of potential hotspots of land use/land cover change is rarely attempted to make future inferences for [...]
The root to the Galápagos mantle plume on the core-mantle boundary
Published: 2022-07-01
Subjects: Earth Sciences, Physical Sciences and Mathematics
Ultra-low velocity zones (ULVZs) are thin anomalous patches on the boundary between the Earth's core and mantle, revealed by their effects on the seismic waves that propagate through them. Here we map a broad ULVZ near the Galápagos hotspot using shear-diffracted waves. Forward modelling assuming a cylindrical shape shows the patch is ~600 km wide, ~20 km high, and its shear velocities are ~25% [...]
Reconstructing Rotomahana Basin topography to disclose the lost White Terraces─ New Zealand’s Eighth Wonder of the World
Published: 2022-07-05
Subjects: Geographic Information Sciences, Geomorphology, Other Earth Sciences, Other Environmental Sciences, Physical and Environmental Geography, Spatial Science, Stratigraphy, Volcanology
The greatest geoscience and tourist attractions in the southern hemisphere were the Pink and White Terraces, the lost Eighth Wonder of the World. British, American and European tourists bypassed local calcareous terraces, for the sea voyage to New Zealand where the siliceous terraces astonished a global audience. Their allure remains. In 1886, the Mount Tarawera eruption buried the terraces. They [...]
Geochemical evidence for the nonexistence of supercritical geothermal fluids at the Yangbajing geothermal field, southern Tibet
Published: 2022-07-07
Subjects: Hydrology, Oil, Gas, and Energy
Exploring and exploiting high-temperature (even supercritical) geothermal resources are significant to meet energy demands and reduce carbon emissions. The Yangbajing geothermal field is the most exploited in China, with the currently highest temperature (329.8 °C) measured in a geothermal well. However, whether there are supercritical geothermal fluids beneath the deep parts of this geothermal [...]
The Lock-Down Effects of COVID-19 on the Air Pollution Indices in Iran and Its Neighbors
Published: 2022-07-02
Subjects: Applied Statistics, Environmental Public Health, Environmental Sciences, Environmental Studies, Near and Middle Eastern Studies, Other Statistics and Probability, Statistical Methodology, Statistical Models
Introduction The Covid-19 restrictions have a lot of various peripheral negative and positive effects like economic shocks and decreasing air pollution, respectively. Many studies showed NO2 reduction in most parts of the world. Method Iran and its land and maritime neighbors have about 7.4% of the world population and 6.3% and 5.8% of World COVID-19 cases and deaths, respectively. The air [...]
Pore-scale imaging of hydrogen displacement and trapping in porous media
Published: 2022-07-05
Subjects: Physical Sciences and Mathematics
Hydrogen can act as an energy store to balance supply and demand in the renewable energy sector. Hydrogen storage in subsurface porous media could deliver high storage capacities but the volume of recoverable hydrogen is unknown. We imaged the displacement and capillary trapping of hydrogen by brine in a Clashach sandstone cylinder at 2-7 MPa pore fluid pressure using X-ray computed [...]
A geothermal heat flow model of Africa based on Random Forest Regression
Published: 2022-07-07
Subjects: Physical Sciences and Mathematics
We generate a geothermal heat flow model over Africa using random forest regression based on sixteen different geophysical and geological quantities (among them are Moho depth, Curie temperature depth, gravity anomalies, topography, and seismic wave velocities). The training of the random forest is based on direct heat flow measurements collected in the compilation of Lucazeau (2019). The final [...]
Initiation of deposition in supercritical turbidity currents downstream of a slope break.
Published: 2022-07-07
Subjects: Earth Sciences
Turbidity currents flowing across the ocean floor encounter changes of the local bathymetry including abrupt reductions in slope gradient also known as slope breaks. Turbidity currents flowing across a slope break will change their flow dynamics and may start to deposit as a consequence. Previous experiments on turbidity currents crossing a slope break have indeed observed abrupt changes of flow [...]
Climate-Driven Risk of Extreme Wildfire in California
Published: 2022-07-09
Subjects: Physical Sciences and Mathematics
California has experienced increased instances of extreme wildfire behavior in recent years, but the extent to which this is due to anthropogenic warming has been difficult to determine. Here we quantify empirical relationships between temperature and the risk of extreme daily wildfire growth (>10,000 acres) in California and use these relationships to estimate how extreme growth risk is changing [...]
Mercury stable isotope composition of lichens and mosses from northern Eurasia
Published: 2022-07-07
Subjects: Physical Sciences and Mathematics
Mercury (Hg) concentrations in lichens and mosses can be used as surrogates for atmospheric Hg deposition to continental surfaces. In this study we collected and analyzed Hg concentrations and isotopic composition of epiphytic tree lichens and terricolous lichens and mosses from remote locations across the Eurasian Arctic and sub-Arctic (50 to 72o N, 30 to 180o E). Total Hg (THg) concentrations [...]
High-Precision Triple Oxygen Isotope Analysis of Carbon Dioxide by Tunable Infrared Laser Absorption Spectroscopy
Published: 2022-07-12
Subjects: Physical Sciences and Mathematics
Precision measurements of the stable isotope ratios of oxygen (18O/16O, 17O/16O) in CO2 are critical to atmospheric monitoring and terrestrial climate research. High-precision 17O measurements by isotope ratio mass spectrometry (IRMS) are challenging because they require complicated sample preparation procedures, long measurement times, and relatively large samples sizes. Recently, tunable [...]
The Role of Salt Tectonics in the Energy Transition: An Overview and Future Challenges
Published: 2022-07-07
Subjects: Physical Sciences and Mathematics
The fundamental properties of salt have long been exploited in the search for hydrocarbons, as they influence many of the hydrocarbon play elements. This industrial application has driven the pursuit of salt tectonic knowledge over the last century and led to major conceptual advances in the field. However, the current need, and social-political demand, to decarbonize suggests that the [...]
Comparison of methods for coupled earthquake and tsunami modeling
Published: 2022-07-09
Subjects: Geophysics and Seismology
Tsunami generation by offshore earthquakes is a problem of scientific interest and practical relevance, and one that requires numerical modeling for data interpretation and hazard assessment. Most numerical models utilize two-step methods with one-way coupling between separate earthquake and tsunami models, based on approximations that might limit the applicability and accuracy of the resulting [...]
Machine-learning correction of the local effects on neutron monitor and muon detector count rates at Syowa Station in the Antarctic
Published: 2022-07-09
Subjects: Physical Sciences and Mathematics
Solar modulation of galactic cosmic rays around the solar minimum in 2019-2020 looks different in the secondary neutrons and muons observed at the ground. To compare the solar modulation of primary cosmic rays in detail, we must remove the possible seasonal variations caused by the atmosphere and surrounding environment. As such surrounding environment effects, we evaluate the snow cover effect [...]
Thermobar: An Open-Source Python3 Tool for Thermobarometry and Hygrometry
Published: 2022-07-09
Subjects: Physical Sciences and Mathematics
We present Thermobar, a new open-source Python3 package for calculating pressures, temperatures, and melt compositions from mineral and mineral-melt equilibrium. Thermobar allows users to perform calculations with >100 popular parametrizations involving liquid, olivine-liquid, olivine-spinel, pyroxene only, pyroxene-liquid, two pyroxene, feldspar-liquid, two feldspar, amphibole only, [...]