Articles | Volume 10, issue 6
https://doi.org/10.5194/esurf-10-1097-2022
© 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-10-1097-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Episodic sediment supply to alluvial fans: implications for fan incision and morphometry
Anya S. Leenman
CORRESPONDING AUTHOR
Department of Geography, University of British Columbia, Vancouver, Canada
School of Geography and the Environment, University of Oxford, Oxford, UK
Brett C. Eaton
Department of Geography, University of British Columbia, Vancouver, Canada
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Nastaran Nematollahi, Brett Eaton, and Sarah Davidson
EGUsphere, https://doi.org/10.5194/egusphere-2025-5934, https://doi.org/10.5194/egusphere-2025-5934, 2026
This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
Short summary
Short summary
We studied how river channels on an alluvial fan shift and reorganize over time. Using a physical experiment and high-resolution images, we tracked how the main channel moved and when it suddenly jumped to new paths. We found that small changes in how sediment moves across the fan can delay or prevent major shifts, showing that fans often regulate themselves in ways that help explain their unpredictable behavior.
David L. Adams and Brett C. Eaton
Earth Surf. Dynam., 10, 895–907, https://doi.org/10.5194/esurf-10-895-2022, https://doi.org/10.5194/esurf-10-895-2022, 2022
Short summary
Short summary
Channel processes under flood conditions are important for river science and management as they involve high volumes of sediment transport and erosion. However, these processes remain poorly understood as the data are difficult to collect. Using a physical model of a river, we found that simple equations based on the mean shear stress and median grain size predicted sediment transport as accurately as ones that accounted for the full range of shear stresses.
William H. Booker and Brett C. Eaton
Earth Surf. Dynam., 10, 247–260, https://doi.org/10.5194/esurf-10-247-2022, https://doi.org/10.5194/esurf-10-247-2022, 2022
Short summary
Short summary
Channel behaviour is a qualitative aspect of river research that needs development to produce a framework of analysis between and within types of channels. We seek to produce a quantitative metric that can capture how a channel changes using a pair of experiments and collecting easy to obtain data. We demonstrate that this new technique is capable of discerning between river types and may provide a new tool with which we may describe channel behaviour.
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Short summary
The supply of sediment (sand and gravel) carried by a stream out of a steep mountain valley is widely thought to control the gradient of the fan-shaped landforms that streams often build where they leave their valley. We tested this idea in a set of
sandboxexperiments with oscillating high and low sediment supply. Even though the average sediment supply never changed, longer oscillations built flatter fans, indicating how wetter climates might affect these mountain landforms.
The supply of sediment (sand and gravel) carried by a stream out of a steep mountain valley is...