Articles | Volume 25, issue 12
https://doi.org/10.5194/nhess-25-4863-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-25-4863-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Deep learning-based object detection on LiDAR-derived hillshade images: insights into grain size distribution and longitudinal sorting of debris flows
Paul E. Schmid
Chair of Engineering Geology, Department of Earth and Planetary Sciences, ETH Zürich, Zürich, Switzerland
Jacob Hirschberg
CORRESPONDING AUTHOR
Chair of Engineering Geology, Department of Earth and Planetary Sciences, ETH Zürich, Zürich, Switzerland
Swiss Federal Institute for Forest, Snow, and Landscape Research WSL, Birmensdorf, Switzerland
Raffaele Spielmann
Chair of Engineering Geology, Department of Earth and Planetary Sciences, ETH Zürich, Zürich, Switzerland
Swiss Federal Institute for Forest, Snow, and Landscape Research WSL, Birmensdorf, Switzerland
Jordan Aaron
Chair of Engineering Geology, Department of Earth and Planetary Sciences, ETH Zürich, Zürich, Switzerland
Swiss Federal Institute for Forest, Snow, and Landscape Research WSL, Birmensdorf, Switzerland
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Induced earthquakes present a major obstacle for developing geoenergy resources. These occur during hydraulic stimulations that enhance fluid pathways in the rock. In the Bedretto Underground Laboratory, hydraulic stimulations are investigated in a downscaled manner. A workflow to analyze the hazard posed by induced earthquakes is applied at different stages of the test program. The hazard estimates illustrate the difficulty in reducing the uncertainty due to the variable seismogenic responses.
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EGUsphere, https://doi.org/10.5194/egusphere-2025-2788, https://doi.org/10.5194/egusphere-2025-2788, 2025
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In mid-May, 2023, the village of Brienz/Brinzauls in the Swiss canton of Graubunden was evacuated, and one month later a flowlike landslide emplaced with velocities of ~25 m/s and narrowly missed impacting the village. Landslides at this site have emplaced with velocities that can vary by 5 order-of-magnitude, a puzzling observation which we analyse in the present work. Our results show that the range of scenarios usually considered in landslide risk analyses must be expanded.
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Debris-flow prediction is often based on rainfall thresholds, but uncertainty assessments are rare. We established rainfall thresholds using two approaches and find that 25 debris flows are needed for uncertainties to converge in an Alpine basin and that the suitable method differs for regional compared to local thresholds. Finally, we demonstrate the potential of a statistical learning algorithm to improve threshold performance. These findings are helpful for early warning system development.
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Short summary
Debris flows are fast-moving water-sediment mixtures in steep channels, posing risks to infrastructure and lives. Traditional analysis is slow and labor-intensive. This study presents a method using laserscanners and deep learning to detect and track moving objects during active events. By converting three-dimensional data to two-dimensional images, it enables fast, accurate measurement of object speed and size. This improves debris-flow monitoring, enhancing hazard understanding and mitigation.
Debris flows are fast-moving water-sediment mixtures in steep channels, posing risks to...
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