Articles | Volume 10, issue 5
https://doi.org/10.5194/esurf-10-953-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-10-953-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Oct 2022
Research article |
| 07 Oct 2022
| 07 Oct 2022
Grain size of fluvial gravel bars from close-range UAV imagery – uncertainty in segmentation-based data
Institute of Geological Sciences, University of Bern,
Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Ariel Henrique Do Prado
Institute of Geological Sciences, University of Bern,
Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Philippos Garefalakis
Institute of Geological Sciences, University of Bern,
Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Alessandro Lechmann
Institute of Geological Sciences, University of Bern,
Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Alexander Whittaker
Department of Earth Science and Engineering, Imperial College, South Kensington Campus, London, SW7 2AZ, United Kingdom
Fritz Schlunegger
Institute of Geological Sciences, University of Bern,
Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
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Renas I. Koshnaw, Fritz Schlunegger, and Daniel F. Stockli
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As continental plates collide, mountain belts grow. This study investigated the provenance of rocks from the northwestern segment of the Zagros mountain belt to unravel the convergence history of the Arabian and Eurasian plates. Provenance data synthesis and field relationships suggest that the Zagros Mountains developed as a result of the oceanic crust emplacement on the Arabian continental plate, followed by the Arabia–Eurasia collision and later uplift of the broader region.
Owen A. Anfinson, Daniel F. Stockli, Joseph C. Miller, Andreas Möller, and Fritz Schlunegger
Solid Earth, 11, 2197–2220, https://doi.org/10.5194/se-11-2197-2020, https://doi.org/10.5194/se-11-2197-2020, 2020
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We present new U–Pb age data to provide insights into the source of sediment for the Molasse Sedimentary Basin in Switzerland. The paper aims to help shed light on the processes that built the Central Alpine Mountains between ~35 and ~15 Ma. A primary conclusion drawn from the results is that at ~21 Ma there was a significant change in the sediment sources for the basin. We feel this change indicates major tectonic changes within the Central Alps.
Samuel Mock, Christoph von Hagke, Fritz Schlunegger, István Dunkl, and Marco Herwegh
Solid Earth, 11, 1823–1847, https://doi.org/10.5194/se-11-1823-2020, https://doi.org/10.5194/se-11-1823-2020, 2020
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Based on thermochronological data, we infer thrusting along-strike the northern rim of the Central Alps between 12–4 Ma. While the lithology influences the pattern of thrusting at the local scale, we observe that thrusting in the foreland is a long-wavelength feature occurring between Lake Geneva and Salzburg. This coincides with the geometry and dynamics of the attached lithospheric slab at depth. Thus, thrusting in the foreland is at least partly linked to changes in slab dynamics.
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Short summary
Grain size data are important for studying and managing rivers, but they are difficult to obtain in the field. Therefore, methods have been developed that use images from small and remotely piloted aircraft. However, uncertainty in grain size data from such image-based products is understudied. Here we present a new way of uncertainty estimation that includes fully modeled errors. We use this technique to assess the effect of several image acquisition aspects on grain size uncertainty.
Grain size data are important for studying and managing rivers, but they are difficult to obtain...
