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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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.
Cited articles
Attal, M., Mudd, S. M., Hurst, M. D., Weinman, B., Yoo, K., and Naylor, M.:
Impact of change in erosion rate and landscape steepness on hillslope and
fluvial sediments grain size in the Feather River basin (Sierra Nevada,
California), Earth Surf. Dynam., 3, 201–222, https://doi.org/10.5194/esurf-3-201-2015, 2015.
Bekaddour, T., Schlunegger, F., Attal, M., and Norton, K. P.: Lateral
sediment sources and knickzones as controls on spatio-temporal variations of
sediment transport in an Alpine river, Sedimentology, 60, 342–357,
https://doi.org/10.1111/sed.12009, 2013.
Brasington, J., Vericat, D., and Rychkov, I.: Modeling river bed morphology,
roughness, and surface sedimentology using high resolution terrestrial laser
scanning, Water Resour. Res., 48, 1–18, https://doi.org/10.1029/2012WR012223, 2012.
Bunte, K. and Abt, S. R.: Sampling Surface and Subsurface Particle-Size
Distributions in Wadable Gravel- and Cobble-Bed Streams for Analyses in
Sediment Transport, Hydraulics, and Streambed Monitoring, 428 pp. https://doi.org/10.2737/RMRS-GTR-74, 2001.
Buscombe, D.: Estimation of grain-size distributions and associated
parameters from digital images of sediment, Sediment. Geol., 210, 1–10,
https://doi.org/10.1016/j.sedgeo.2008.06.007, 2008.
Buscombe, D.: Transferable wavelet method for grain-size distribution from
images of sediment surfaces and thin sections, and other natural granular
patterns, Sedimentology, 60, 1709–1732, https://doi.org/10.1111/sed.12049, 2013.
Buscombe, D.: SediNet: a configurable deep learning model for mixed
qualitative and quantitative optical granulometry, Earth Surf. Proc. Land., 45, 638–651, https://doi.org/10.1002/esp.4760, 2020.
Buscombe, D., Rubin, D. M., and Warrick, J. A.: A universal approximation of
grain size from images of noncohesive sediment, J. Geophys. Res.-Earth, 115, 1–17, https://doi.org/10.1029/2009jf001477, 2010.
Butler, J. B., Lane, S. N., and Chandler, J. H.: Automated extraction of
grain-size data from gravel surfaces using digital image processing, J.
Hydraul. Res., 39, 519–529, https://doi.org/10.1080/00221686.2001.9628276, 2001.
Carbonneau, P. E. and Dietrich, J. T.: Cost-effective non-metric
photogrammetry from consumer-grade sUAS: implications for direct georeferencing of structure from motion photogrammetry, Earth Surf. Proc.
Land., 42, 473–486, https://doi.org/10.1002/esp.4012, 2017.
Carbonneau, P. E., Lane, S. N., and Bergeron, N. E.: Cost-effective non-metric close-range digital photogrammetry and its application to a study
of coarse gravel river beds, Int. J. Remote Sens., 24, 2837–2854,
https://doi.org/10.1080/01431160110108364, 2003.
Carbonneau, P. E., Lane, S. N., and Bergeron, N. E.: Catchment-scale mapping
of surface grain size in gravel bed rivers using airborne digital imagery,
Water Resour. Res., 40, 1–11, https://doi.org/10.1029/2003WR002759, 2004.
Carbonneau, P. E., Bergeron, N., and Lane, S. N.: Automated grain size
measurements from airborne remote sensing for long profile measurements of
fluvial grain sizes, Water Resour. Res., 41, 1–9, https://doi.org/10.1029/2005WR003994, 2005.
Carbonneau, P. E., Bizzi, S., and Marchetti, G.: Robotic photosieving from
low-cost multirotor sUAS: a proof-of-concept, Earth Surf. Proc. Land., 43, 1160–1166, https://doi.org/10.1002/esp.4298, 2018.
Carrivick, J. L. and Smith, M. W.: Fluvial and aquatic applications of
Structure from Motion photogrammetry and unmanned aerial vehicle/drone
technology, Wiley Interdisciplin. Rev. Water, 6, e1328,
https://doi.org/10.1002/wat2.1328, 2019.
Chardon, V., Piasny, G., and Schmitt, L.: Comparison of software accuracy to estimate the bed grain size distribution from digital images: A test performed along the Rhine River, River Res. Appl., 38, 358–367, https://doi.org/10.1002/rra.3910, 2022.
Chen, X., Hassan, M. A., and Fu, X.: Convolutional neural networks for
image-based sediment detection applied to a large terrestrial and airborne
dataset, Earth Surf. Dynam., 10, 349–366, https://doi.org/10.5194/esurf-10-349-2022, 2022.
Church, M., Hassan, M. A., and Wolcott, J. F.: Stabilizing self-organized
structures in gravel-bed stream channels: Field and experimental observations, Water Resour. Res., 34, 3169–3179, https://doi.org/10.1029/98WR00484, 1998.
Cook, K. L. and Dietze, M.: Short Communication: A simple workflow for
robust low-cost UAV-derived change detection without ground control points,
Earth Surf. Dynam., 7, 1009–1017, https://doi.org/10.5194/esurf-7-1009-2019, 2019.
Detert, M. and Weitbrecht, V.: Automatic object detection to analyze the
geometry of gravel grains – A free stand-alone tool, River Flow 2012, Proc. Int. Conf. Fluv. Hydraul., 1, 595–600, 2012.
Dunne, K. B. J. and Jerolmack, D. J.: Evidence of, and a proposed explanation for, bimodal transport states in alluvial rivers, Earth Surf. Dynam., 6, 583–594, https://doi.org/10.5194/esurf-6-583-2018, 2018.
Eaton, B. C., Moore, R. D., and MacKenzie, L. G.: Percentile-based grain
size distribution analysis tools (GSDtools) – estimating confidence limits
and hypothesis tests for comparing two samples, Earth Surf. Dynam., 7,
789–806, https://doi.org/10.5194/esurf-7-789-2019, 2019.
Eltner, A. and Sofia, G.: Structure from motion photogrammetric technique,
in: 1st Edn., Elsevier B.V., 1–24, https://doi.org/10.1016/B978-0-444-64177-9.00001-1, 2020.
Eltner, A., Kaiser, A., Castillo, C., Rock, G., Neugirg, F., and Abellán, A.: Image-based surface reconstruction in geomorphometry-merits, limits and developments, Earth Surf. Dynam., 4, 359–389, https://doi.org/10.5194/esurf-4-359-2016, 2016.
Fonstad, M. A., Dietrich, J. T., Courville, B. C., Jensen, J. L., and
Carbonneau, P. E.: Topographic structure from motion: A new development in
photogrammetric measurement, Earth Surf. Proc. Land., 38, 421–430,
https://doi.org/10.1002/esp.3366, 2013.
Graham, D. J., Reid, I., and Rice, S. P.: Automated sizing of coarse-grained
sediments: Image-processing procedures, Math. Geol., 37, 1–28,
https://doi.org/10.1007/s11004-005-8745-x, 2005.
Grant, G. E.: The Geomorphic Response of Gravel-Bed Rivers to Dams:
Perspectives and Prospects, in: Gravel-Bed Rivers, John Wiley & Sons, Ltd, Chichester, UK, 165–181, https://doi.org/10.1002/9781119952497.ch15, 2012.
Griffiths, D. and Burningham, H.: Comparison of pre- and self-calibrated
camera calibration models for UAS-derived nadir imagery for a SfM application, Prog. Phys. Geogr., 43, 215–235, https://doi.org/10.1177/0309133318788964, 2019.
Hastedt, H., Luhmann, T., Przybilla, H.-J., and Rofallski, R.: Evaluation Of Interior Orientation Modelling For Cameras With Aspheric Lenses And Image Pre-Processing With Special Emphasis To SFM Reconstruction, Int. Arch.
Photogram. Remote Sens. Spat. Inf. Sci., XLIII-B2-2, 17–24,
https://doi.org/10.5194/isprs-archives-XLIII-B2-2021-17-2021, 2021.
Ibbeken, H. and Schleyer, R.: Photo-sieving: A method for grain-size analysis of coarse-grained, unconsolidated bedding surfaces, Earth Surf. Proc. Land., 11, 59–77, https://doi.org/10.1002/esp.3290110108, 1986.
James, M. R. and Robson, S.: Straightforward reconstruction of 3D surfaces
and topography with a camera: Accuracy and geoscience application, J.
Geophys. Res.-Earth, 117, F03017, https://doi.org/10.1029/2011JF002289, 2012.
James, M. R. and Robson, S.: Mitigating systematic error in topographic
models derived from UAV and ground-based image networks, Earth Surf. Proc. Land., 39, 1413–1420, https://doi.org/10.1002/esp.3609, 2014.
James, M. R., Robson, S., and Smith, M. W.: 3-D uncertainty-based topographic change detection with structure-from-motion photogrammetry: precision maps for ground control and directly georeferenced surveys, Earth Surf. Proc. Land., 42, 1769–1788, https://doi.org/10.1002/esp.4125, 2017a.
James, M. R., Robson, S., d'Oleire-Oltmanns, S., and Niethammer, U.:
Optimising UAV topographic surveys processed with structure-from-motion:
Ground control quality, quantity and bundle adjustment, Geomorphology, 280, 51–66, https://doi.org/10.1016/j.geomorph.2016.11.021, 2017b.
James, M. R., Antoniazza, G., Robson, S., and Lane, S. N.: Mitigating
systematic error in topographic models for geomorphic change detection:
accuracy, precision and considerations beyond off-nadir imagery, Earth Surf.
Proc. Land., 45, 2251–2271, https://doi.org/10.1002/esp.4878, 2020.
Kondolf, G. M. and Wolman, M. G.: The sizes of salmonid spawning gravels,
Water Resour. Res., 29, 2275–2285, https://doi.org/10.1029/93WR00402, 1993.
Lamb, M. P. and Venditti, J. G.: The grain size gap and abrupt gravel-sand
transitions in rivers due to suspension fallout, Geophys. Res. Lett., 43,
3777–3785, https://doi.org/10.1002/2016GL068713, 2016.
Lang, N., Irniger, A., Rozniak, A., Hunziker, R., Wegner, J. D., and
Schindler, K.: GRAINet: mapping grain size distributions in river beds from
UAV images with convolutional neural networks, Hydrol. Earth Syst. Sci., 25,
2567–2597, https://doi.org/10.5194/hess-25-2567-2021, 2021.
Mair, D., Henrique, A., Prado, D., Garefalakis, P., Lechmann, A., Whittaker, A., and Schlunegger, F.: Data and code for: Grain size of fluvial gravel bars from close-range UAV imagery – uncertainty in segmentation-based data, Zenodo [code and data set], https://doi.org/10.5281/zenodo.6415047, 2022.
Marchetti, G., Bizzi, S., Belletti, B., Lastoria, B., Comiti, F., and Carbonneau, P. E.: Mapping riverbed sediment size from Sentinel‐2 satellite data, Earth Surf. Proc. Land., 47, 2544–2559, https://doi.org/10.1002/esp.5394, 2022.
O'Connor, J., Smith, M. J., and James, M. R.: Cameras and settings for aerial surveys in the geosciences: Optimising image data, Prog. Phys. Geogr., 41, 325–344, https://doi.org/10.1177/0309133317703092, 2017.
Over, J.-S. R., Ritchie, A. C., Kranenburg, C. J., Jenna A., B., Buscombe,
D., Noble, T., Sherwood, C. R., Warrick, J. A., and Wernette, P. A.: Processing Coastal Imagery With Agisoft Metashape Professional Edition ,
Version 1.6 — Structure From Motion Workflow Documentation, US Geol.
Surv. Open-File Rep. 2021–1039, US Geological Survey, 1–45, https://doi.org/10.3133/ofr20211039, 2021.
Pearson, E., Smith, M. W., Klaar, M. J., and Brown, L. E.: Can high
resolution 3D topographic surveys provide reliable grain size estimates in
gravel bed rivers?, Geomorphology, 293, 143–155, https://doi.org/10.1016/j.geomorph.2017.05.015, 2017.
Piégay, H., Arnaud, F., Belletti, B., Bertrand, M., Bizzi, S., Carbonneau, P., Dufour, S., Liébault, F., Ruiz-Villanueva, V., and
Slater, L.: Remotely sensed rivers in the Anthropocene: state of the art and
prospects, Earth Surf. Proc. Land., 45, 157–188, https://doi.org/10.1002/esp.4787, 2020.
Pitlick, J., Recking, A., Liebault, F., Misset, C., Piton, G., and Vazquez-Tarrio, D.: Sediment Production in French Alpine Rivers, Water
Resour. Res., 57, 1–23, https://doi.org/10.1029/2021wr030470, 2021.
Purinton, B. and Bookhagen, B.: Introducing PebbleCounts: a grain-sizing tool for photo surveys of dynamic gravel-bed rivers, Earth Surf. Dynam., 7, 859–877, https://doi.org/10.5194/esurf-7-859-2019, 2019.
Purinton, B. and Bookhagen, B.: Tracking Downstream Variability in Large
Grain-Size Distributions in the South-Central Andes, J. Geophys. Res.-Earth, 126, 1–29, https://doi.org/10.1029/2021JF006260, 2021.
Rubin, D. M.: A simple autocorrelation algorithm for determining grain size
from digital images of sediment, J. Sediment. Res., 74, 160–165,
https://doi.org/10.1306/052203740160, 2004.
Sanz-Ablanedo, E., Chandler, J. H., Ballesteros-Pérez, P., and
Rodríguez-Pérez, J. R.: Reducing systematic dome errors in digital
elevation models through better UAV flight design, Earth Surf. Proc. Land., 45, 2134–2147, https://doi.org/10.1002/esp.4871, 2020.
Schlunegger, F., Delunel, R., and Garefalakis, P.: Short communication:
Field data reveal that the transport probability of clasts in Peruvian and
Swiss streams mainly depends on the sorting of the grains, Earth Surf. Dynam., 8, 717–728, https://doi.org/10.5194/esurf-8-717-2020, 2020.
Shields, A.: Anwendung der Aehnlichkeitsmechanik und der Turbulenzforschung auf die Geschiebebewegung, Mitteilungen der Preuss. Versuchanstalt für Wasserbau und Schiffbau, 26, 1–26, 1936.
Smith, M. W. and Vericat, D.: From experimental plots to experimental
landscapes: Topography, erosion and deposition in sub-humid badlands from
Structure-from-Motion photogrammetry, Earth Surf. Proc. Land., 40, 1656–1671, https://doi.org/10.1002/esp.3747, 2015.
Sulaiman, M. S., Sinnakaudan, S. K., Ng, S. F., and Strom, K.: Application
of automated grain sizing technique (AGS) for bed load samples at Rasil
River: A case study for supply limited channel, Catena, 121, 330–343, https://doi.org/10.1016/j.catena.2014.05.013, 2014.
Swisstopo: Swiss Positioning Service swipos,
https://www.swisstopo.admin.ch/en/geodata/geoservices/swipos.html, last access: 26 February 2022.
Tofelde, S., Bernhardt, A., Guerit, L., and Romans, B. W.: Times Associated
With Source-to-Sink Propagation of Environmental Signals During Landscape
Transience, Front. Earth Sci., 9, 1–26, https://doi.org/10.3389/feart.2021.628315, 2021.
Van den Berg, F. and Schlunegger, F.: Alluvial cover dynamics in response to
floods of various magnitudes: The effect of the release of glaciogenic
material in a Swiss Alpine catchment, Geomorphology, 141–142, 121–133, https://doi.org/10.1016/j.geomorph.2011.12.030, 2012.
Vázquez-Tarrío, D., Borgniet, L., Liébault, F., and Recking, A.: Using UAS optical imagery and SfM photogrammetry to characterize the surface grain size of gravel bars in a braided river (Vénéon River, French Alps), Geomorphology, 285, 94–105, https://doi.org/10.1016/j.geomorph.2017.01.039, 2017.
Whittaker, A. C., Attal, M., and Allen, P. A.: Characterising the origin,
nature and fate of sediment exported from catchments perturbed by active
tectonics, Basin Res., 22, 809–828, https://doi.org/10.1111/j.1365-2117.2009.00447.x, 2010.
Wohl, E. E., Anthony, D. J., Madsen, S. W., and Thompson, D. M.: A
comparison of surface sampling methods for coarse fluvial sediments, Water
Resour. Res., 32, 3219–3226, https://doi.org/10.1029/96WR01527, 1996.
Wolcott, J. and Church, M.: Strategies for sampling spatially heterogeneous
phenomena: the example of river gravels, J. Sediment. Petrol., 61, 534–543,
https://doi.org/10.1306/D4267753-2B26-11D7-8648000102C1865D, 1991.
Wolman, M. G.: A method of sampling coarse river-bed material, Trans. Am.
Geophys. Union, 35, 951, https://doi.org/10.1029/TR035i006p00951, 1954.
Woodget, A. S. and Austrums, R.: Subaerial gravel size measurement using
topographic data derived from a UAV-SfM approach, Earth Surf. Proc. Land., 42, 1434–1443, https://doi.org/10.1002/esp.4139, 2017.
Woodget, A. S., Fyffe, C., and Carbonneau, P. E.: From manned to unmanned
aircraft: Adapting airborne particle size mapping methodologies to the
characteristics of sUAS and SfM, Earth Surf. Proc. Land., 43, 857–870, https://doi.org/10.1002/esp.4285, 2018.
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...
