Preprints
There are 4717 Preprints listed.
Increased crevassing across accelerating Greenland Ice Sheet margins
Published: 2023-09-02
Subjects: Glaciology
The extent of surface crevassing on the Greenland Ice Sheet is a large source of uncertainty in processes controlling mass loss, including iceberg calving, ice rheology, and water routing. However, no work to date 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 [...]
Garnet fracturing reveals ancient unstable slip events hosted in plate interface metasediments
Published: 2023-09-01
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 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 [...]
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 [...]
Towards an astrochronological framework for the lower Paleoproterozoic Kuruman and Brockman Iron Formations
Published: 2023-09-01
Subjects: Earth Sciences, Physical Sciences and Mathematics, Stratigraphy
Recent evidence for astronomical-induced cycles in banded iron formations (BIFs) hints at the intriguing possibility of developing astrochronological, i.e. precise time-stratigraphic, frameworks for the earliest Proterozoic as also reconstructed for parts of the Mesozoic and Paleozoic. The ca 2.47-Ga Kuruman Iron Formation (Griqualand West Basin, South Africa) and Dales Gorge Member of the [...]
SeisMIC - an Open Source Python Toolset to Compute Velocity Changes from Ambient Seismic Noise
Published: 2023-09-01
Subjects: Computer Sciences, Earth Sciences, Environmental Monitoring, Environmental Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We present SeisMIC, a fast, versatile, and adaptable open-source software to estimate seismic velocity changes from ambient seismic noise. SeisMIC includes a broad set of tools and functions to facilitate end-to-end processing of ambient noise data, from data retrieval and raw data analysis via spectrogram computation, over waveform coherence analysis, to post-processing of the final velocity [...]
Understanding Europe’s forest harvesting regimes
Published: 2023-08-31
Subjects: Environmental Sciences, Forest Management, Forest Sciences, Life Sciences, Natural Resources Management and Policy, Nature and Society Relations
The functioning and structure of most European forests are actively shaped by intensive human use. Harvesting of wood is one of the key processes of forest management, making it a crucial element to include in any large-scale analysis of forest ecosystems. Yet, our understanding of how forests are harvested across Europe is limited, as the true harvest regimes – a realisation of decisions made by [...]
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 [...]
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 free trade is risk sharing, because global aggregate production is more stable than that of individual countries which may be adversely affected by extremes. Here we test the hypothesis that diverse sourcing of crops from multiple trading [...]
Comprehensive review of geomechanics of underground hydrogen storage in depleted reservoirs and salt caverns
Published: 2023-08-31
Subjects: Applied Mechanics, Earth Sciences
Hydrogen is a promising energy carrier for a low-carbon future energy system, as it can be stored on a megaton scale (equivalent to TWh of energy) in subsurface reservoirs. However, safe and efficient underground hydrogen storage requires a thorough understanding of the geomechanics of the host rock under fluid pressure fluctuations. In this context, we summarize the current state of knowledge [...]
Knowledge Graphs for Seismic Data and Metadata
Published: 2023-08-31
Subjects: Databases and Information Systems, Geophysics and Seismology
The increasing scale and diversity of seismic data, and the growing role of big data in seismology, has raised interest in methods to make data exploration more accessible. This paper presents the use of knowledge graphs (KGs) for representing seismic data and metadata to improve data exploration and analysis, focusing on usability, flexibility, and extensibility. Using constraints derived from [...]
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 [...]