The geomorphic evolution of the Jordan River in recent decades indicates that interaction between incision and high-magnitude floods controls sinuosity changes under increasing mouth gradients during base-level fall. The evolution of the river was analyzed based on digital elevation models, remotely sensed imagery, hydrometric data, and a hydraulic model. The response varies along the river. Near the river mouth, where incision rate is high and a deep channel forms, overbank flooding is less likely. There, large floods exert high shear stress within the confined channel, increasing sinuosity. Upstream, near the migrating knickzone channel gradients also increase, incision is more moderate and floods continue to overtop the banks, favoring meander chute cutoffs. The resulting channel has a downstream well-confined meandering segment and an upstream low-sinuosity segment. These new insights regarding spatial differences along an incising channel can improve interpretations of the evolution of ancient planforms and floodplains that responded to base-level decline.
Bibliographical noteFunding Information:
Acknowledgements—This research was supported by the Israel Science Foundation (grants No. 18/1471 and 18/946) and by the Israeli Government (Geological Survey of Israel project number 40555). We wish to thank the editor, associate editor, John Armitage and an anonymous reviewer, for their thorough comments that greatly improved this paper.
This research was supported by the Israel Science Foundation (grants No. 18/1471 and 18/946) and by the Israeli Government (Geological Survey of Israel project number 40555). We wish to thank the editor, associate editor, John Armitage and an anonymous reviewer, for their thorough comments that greatly improved this paper. Landsat imagery data and SRTM DEM were made available by the U.S. Geological Survey (https://earthexplorer.usgs.gov/). The hydrologic data in this study was provided by the Hydrological Survey of Israel. We wish to thank Vladimir Lyakhovsky for his valuable comments and suggestions regarding the analytical solution of the diffusion equation.
© 2018 John Wiley & Sons, Ltd.
- base-level fall
- channel incision
- channel sinuosity
- overbank floods
ASJC Scopus subject areas
- Geography, Planning and Development
- Earth-Surface Processes
- Earth and Planetary Sciences (miscellaneous)