Preprints
There are 5726 Preprints listed.
A radial hydraulic fracture driven by a Herschel–Bulkley fluid
Published: 2021-05-27
Subjects: Fluid Dynamics, Hydraulic Engineering, Hydrology, Numerical Analysis and Scientific Computing, Oil, Gas, and Energy, Volcanology
We analyse the influence of fluid yield stress on propagation of a radial (penny-shaped) hydraulic fracture in a permeable reservoir. In particular, the Herschel-Bulkley rheological model is adopted that includes yield stress and non-linearity of the shear stress. The rock is assumed to be linear elastic, and the fracture is driven by the point source fluid injection with a constant volumetric [...]
ANALYSIS OF OWNER DRIVEN APPROACH OF HOUSING RECONSTRUCTION AFTER GORKHA EARTHQUAKE 2015: A CASE STUDY OF DHUNIBESHI MUNICIPALITY, DHADING
Published: 2021-05-26
Subjects: Engineering
A 7.6 magnitude earthquake occurred in Gorkha district of Nepal leading more than 9,000 estimated casualties, approximately 23,000 injuries and damages on more than half a million structures. For leading and managing the earthquake recovery and reconstruction in Nepal, a legally mandated agency named National Reconstruction Authority (NRA) was established in December 2015 which facilitate and [...]
Photochemical synthesis of ammonia and amino acids from nitrous oxide
Published: 2021-05-26
Subjects: Life Sciences
Abiotic synthesis of ammonia and amino acids are important for origin of life and early evolution. Ammonia (NH3) and organic nitrogen species may be possibly produced from nitrous oxide (N2O), which is a second abundant nitrogen species in the atmosphere. Here, we report a new photochemical experiment and evaluate whether N2O can be used as a nitrogen source for prebiotic synthesis in the [...]
High-resolution petrographic evidence confirming detrital and biogenic magnetites as remanence carriers for Zongpu carbonates in the Gamba area, South Tibet
Published: 2021-05-26
Subjects: Earth Sciences
Paleocene carbonates from the Gamba area of South Tibet provide the largest paleomagnetic dataset for constraining the paleogeography of the India-Asia collision in the early stage. The characteristic remanences (ChRMs) obtained from this unit were, however, argued for a chemical remagnetization via orogenic fluids. This study carries out a high-resolution petrographic study on the Paleocene [...]
Satellites unveil easily-fixable super-emissions in one of the world's largest methane hotspot regions
Published: 2021-05-26
Subjects: Environmental Sciences
Reduction of fossil fuel-related methane emissions has been identified as an essential means for climate change mitigation, but emission source identification remains elusive. We combine three complementary satellite data sets to survey single methane emission sources on the west coast of Turkmenistan, one of the largest methane hotspots in the world. We found 29 different super-emitters active [...]
Defining a Sustainable Development Target Space for 2030 and 2050
Published: 2021-05-24
Subjects: Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Natural Resource Economics, Other Environmental Sciences, Physical Sciences and Mathematics, Social and Behavioral Sciences, Sustainability
By adopting the Sustainable Development Goals (SDGs), countries worldwide agreed to an agenda for achieving a prosperous, socially inclusive and environmentally sustainable future for all1. This ambition, however, also exposes a critical knowledge gap since science-based insights on how to achieve the 17 SDGs simultaneously are lacking. Quantitative goal-seeking scenario studies could enable [...]
Modelled Soil Temperature Sensitivity to Variable Snow and Vegetation Conditions in Low-Relief Coastal Mountains, Nunatsiavut and NunatuKavut, Labrador
Published: 2021-05-24
Subjects: Other Applied Mathematics, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics
Understanding permafrost vulnerability and resilience to climate warming is critical for predicting impacts on northern communities and ecosystems. The thermal characteristics of near-surface permafrost are influenced by effects from overlying vegetation and snow cover, both of which are changing in northern environments. The association between vegetation and snow is important in the coastal [...]
Simulating land use change trajectories of the Cerrado Hotspot reveals the importance of considering private property sizes for biodiversity conservation
Published: 2021-05-24
Subjects: Life Sciences
Simulating future land use changes can be an important tool to support decisionmaking, especially in areas that are experiencing rapid anthropogenic pressure, such as the Cerrado – Brazilian savanna. Here we used a spatially-explicit model to identify the main drivers of native vegetation loss in the Cerrado, and then projected this loss for 2050 and 2070. We also analyzed the role of [...]
Meteorites that produce K-feldspar-rich ejecta blankets correspond to mass extinctions.
Published: 2021-05-24
Subjects: Applied Statistics, Atmospheric Sciences, Earth Sciences, Geology, Other Planetary Sciences, Paleontology, Physical Sciences and Mathematics
Meteorite impacts load the atmosphere with dust and cover the Earth‘s surface with debris. They have long been debated as a trigger of mass extinctions through Earth‘s history. Impact winters generally last <100 years, whereas ejecta blankets persist for 10^3-10^5 years. Here we show that only meteorite impacts that emplaced ejecta blankets rich in K-feldspar (Kfs) correlate to Earth system [...]
What sets aeolian dune height?
Published: 2021-05-24
Subjects: Climate, Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology, Stratigraphy
Earth's major sand seas are often populated with giant dunes, up to hundreds of meters in height and kilometers in wavelength. These massive sediment piles, visible from space on our planet and across the Solar System, indicate that conditions for sand transport have persisted for millenia. Unraveling how giant dunes form therefore has implications for understanding atmospheric flows and climatic [...]
A Short Note on the Age of the Marwar Supergroup, NW India
Published: 2021-05-23
Subjects: Earth Sciences
We report a summary of geochronological data derived from detrital zircons in the Marwar Supergroup, Rajasthan, India. Although the age of deposition for the Marwar sequence was inferred to be post-Cryogenian, there is a lack of any direct age data. Two recent papers reached different conclusions based on geochronological data. A Rb-Sr age on a felsic flow within the Sonia sandstone yielded [...]
Automated mineralogy as a novel approach for the compositional and textural characterization of spent lithium-ion batteries
Published: 2021-05-21
Subjects: Engineering
Mechanical recycling processes aim to separate particles based on their physical properties, such as size, shape and density, and physico-chemical surface properties, such as wettability. Secondary materials, including electronic waste, are highly complex and heterogeneous, which complicates recycling processes. In order to improve recycling efficiency, characterization of both recycling process [...]
Causal and Predictive Analysis of Climate Change Using Granger Causality
Published: 2021-05-21
Subjects: Climate
Current climate simulation models provide valuable insights but are highly complicated, with numerous parameters, making them complex for assessing the causal impact of anthropogenic and natural factors on global temperatures. We applied multivariate Granger causality to investigate how combinations of forcings affect Earth's surface and ocean temperatures. Clear causal impact was found due to [...]
Consensus-Based Rock Glacier Inventorying in the Torngat Mountains, Northern Labrador
Published: 2021-05-21
Subjects: Physical Sciences and Mathematics
The Torngat Mountains of northern Labrador are an Arctic cordilleran mountain range located at the southern limit of the Canadian Arctic. Sparse observations of periglacial landforms including rock glaciers and ice-cored moraines imply that permafrost may be widespread, but limited in situ information is available for the region. In this study, we provide the first comprehensive feature inventory [...]
Inferring rheology and geometry of subsurface structures by adjoint-based inversion of principal stress directions
Published: 2021-05-21
Subjects: Geology, Geophysics and Seismology, Tectonics and Structure
Imaging subsurface structures, such as salt domes, magma reservoirs, or subducting plates, is a major challenge in geophysics. Seismic imaging methods are, so far, the most precise methods to open a window into the Earth. However, the methods may not yield the exact depth or size of the imaged feature and may become distorted by phenomena such as seismic anisotropy, fluid flow, or compositional [...]