Preprints
There are 7999 Preprints listed.
Generation of LOMU type alkali basalts in East Asia by melting and melt metasomatism of the asthenospheric mantle by a Paleoproterozoic subducted slab component
Published: 2023-08-30
Subjects: Geochemistry, Geology, Volcanology
The origin of alkali basalts with distinctive time-integrated low U/Pb (low µ, LOMU) from East Asia is controversial due to the complex geochemical and tectonic signatures reported from this region. We report new data on the petrology and geochemistry of the Higashi-Matsuura and Kita-Matsuura alkali basalts from southwest Japan, which confirm the presence of a LOMU-type mantle component below the [...]
Independent estimates of net carbon uptake in croplands: UAV-LiDAR and machine learning vs. eddy-covariance
Published: 2023-08-30
Subjects: Engineering, Life Sciences, Physical Sciences and Mathematics
Understanding sequestration of organic carbon (C) in agroecosystems is of primary importance for greenhouse gas (GHG) accounting in managed ecosystems, reducing the environmental footprint of land use, and inform crediting programs. However, a broader application of precise C accounting is currently constrained by a limited number of direct flux measurements. Aside well-studied ecosystems via the [...]
Yield strength determination based on dissipative energetic transition
Published: 2023-08-30
Subjects: Applied Mechanics, Civil Engineering, Earth Sciences
Mechanical yield strength is one of the most crucial mechanical properties to consider to remain operating in safe elastic regimes. Despite its importance, it remains ambiguous to measure as different disciplines acknowledge different definitions. Most common examples include the deviation from linear elasticity or the peak stress. This difference has significant consequences for the modelling of [...]
Garnet fracturing reveals ancient unstable slip events hosted in plate interface metasediments
Published: 2023-09-02
Subjects: Physical Sciences and Mathematics
A paradox exists between the great number of intermediate-depth earthquakes occurring along active subduction interfaces worldwide and the extreme scarcity of paleo-seismic events recorded in exhumed metasedimentary rocks from ancient subduction zones. Recrystallization, shearing as well as exhumation-related overprinting generally contribute to the nearly-complete erasing of markers of unstable [...]
Deformation and frictional failure of granular media in 3D analog and numerical experiments
Published: 2023-09-01
Subjects: Physical Sciences and Mathematics
Frictional sliding along grain boundaries in brittle shear zones can result in the fragmentation of individual grains, which ultimately can impact slip dynamics. During deformation at small scales, stick-slip motion can occur between grains when existing force chains break due to grain rearrangement or failure, resulting in frictional sliding of granular material. The rearrangement of the grains [...]
The Whakamaru Magmatic System (Taupō Volcanic Zone, New Zealand), Part 1: Evidence from tephra deposits for the eruption of multiple magma types through time
Published: 2023-08-31
Subjects: Physical Sciences and Mathematics
The Whakamaru group eruptions (349 ± 4 ka; Downs et al., 2014) are the largest known eruptions in the history of the young Taupō Volcanic Zone, Aotearoa New Zealand. The complex field relationships of the ignimbrites have thus far obscured the timing and history of their eruption(s). We present new evidence from fall deposits correlated with the Whakamaru eruptions to complement the ignimbrite [...]
The Whakamaru Magmatic System (Taupō Volcanic Zone, New Zealand), Part 2: Evidence from ignimbrite deposits for pre-eruptive distribution of melt-dominated magma and magma mushes
Published: 2023-08-31
Subjects: Physical Sciences and Mathematics
The complex volcanology and petrology of the Whakamaru volcanic deposits in Aotearoa New Zealand have thus far obscured the number of eruptive phases and the relative timing of these eruption(s). We investigate pumice clasts from multiple localities to elucidate the relative timing of the eruptions, with a focus on the pre-eruptive conditions of the melt-dominated magma bodies that fed the [...]
The uncertain future of mountaintop-removal-mined landscapes 2: Modeling the influence of topography and vegetation
Published: 2023-09-02
Subjects: Geomorphology
Erosion following human disturbance threatens ecosystem health and inhibits effective land use. Mountaintop removal/valley fill (MTR/VF) mined landscapes of the Appalachian Coalfields region, USA, provide a unique opportunity to quantify the geomorphic trajectory of disturbed lands. Here we assess how MTR/VF-induced changes to topography and vegetation influence spatiotemporal erosion patterns in [...]
Global trade and the resilience of food supply to extreme weather exposure
Published: 2023-08-31
Subjects: Agriculture, Physical and Environmental Geography, Sustainability
Climate change is increasing the risk of extreme weather events, potentially threatening crop yields and global food security. A key benefit of international trade is risk sharing, because global aggregate production is more stable than that of individual countries which may be adversely affected by extremes. However, countries vary in the degree to which they source commodities from trading [...]
The Role of Continental Heterogeneity on the Evolution of Continental Margin Topography at Subduction Zones
Published: 2023-09-01
Subjects: Earth Sciences, Geophysics and Seismology, Other Earth Sciences, Physical Sciences and Mathematics, Tectonics and Structure
The nature of the overriding plate plays a major role in shaping subduction zone processes. In particular, the highly heterogeneous continental lithosphere modulates intra-plate tectonics and the surface evolution of our planet. However, the role of continental heterogeneity is relatively under-explored for the dynamics of subduction models. We investigate the influence of rheological and density [...]
Machine Learning Photogrammetric Analysis of Images Provides a Scalable Approach to Study Riverbed Grain Size Distributions
Published: 2023-09-01
Subjects: Earth Sciences, Geomorphology, Hydrology
The distribution of sediment grain size in streams and rivers is often quantified by the median grain size (d50), a key metric for understanding and predicting hydrologic and biogeochemical function of streams and rivers. Manual methods to measure d50 are time-consuming and ignore larger grains, while model-based methods to estimate d50 often over-generalize basin characteristics, and therefore [...]
Full-waveform inversion as a tool to predict fault zone properties
Published: 2023-09-02
Subjects: Geology
Understanding the physical properties of fault zones is essential for various subsurface applications, including carbon capture and geologic storage, geothermal energy, and seismic hazard assessment. Despite improvements in fault imaging and visualisation, predicting the physical properties of faults and fault zones in the subsurface remains challenging, even with high-quality seismic reflection [...]
The Role of Normal Fault Growth History in Influencing Fault Seal Potential, Samson Dome, Offshore Norway
Published: 2023-09-02
Subjects: Geology
The growth of normal faults can influence subsurface fluid flow and entrapment within rift basins. However, fault seal studies typically view faults as static structures, with their growth and the potential related temporal changes in hydraulic properties being ignored. In this study, we use borehole data and a high-quality 3D full-stack depth migrated seismic reflection volume to analyse the [...]
An Ice-Free Arctic Ocean During the Last Interglacial: An unsupported statement
Published: 2023-09-01
Subjects: Physical Sciences and Mathematics
The Last Interglacial has attracted the attention of researchers as it was globally characterized by a climate optimum warmer than that of the preindustrial period. In particular, several attempts at reconstructing the Arctic Ocean sea-ice extent of this interval were made based on marine sedimentary archives, all failed to find clear evidence of sea-ice-free conditions. An article published [...]
Increased crevassing across accelerating Greenland Ice Sheet margins
Published: 2023-09-02
Subjects: Glaciology
Surface crevassing on the Greenland Ice Sheet is a large source of uncertainty in processes controlling mass loss, including calving, ice rheology, and water routing. However, no work has comprehensively mapped the location of surface crevasses or examined their evolution through time. Here, we use high-resolution digital elevation models to map the 3-dimensional volume of crevasse fields across [...]