Dunes in the world’s big rivers are characterized by low-angle lee-side slopes and a complex shape

Cisneros, Julia; Best, Jim; van Dijk, Thaiënne; Almeida, Renato Paes de; Amsler, Mario; Boldt, Justin; Freitas, Bernardo; Galeazzi, Cristiano; Huizinga, Richard; Ianniruberto, Marco; Ma, Hongbo; Nittrouer, Jeffrey A.; Oberg, Kevin; Orfeo, Oscar; Parsons, Dan; Szupiany, Ricardo; Wang, Ping; Zhang, Yuanfeng

Abstract

Dunes are present in all the worlds’ big rivers and form critical agents of bedload transport, constitute appreciable sources of bed roughness and flow resistance, and generate stratification that is the most common depositional element of ancient alluvium. Yet our current models of dunes are conditioned by the geometry of bedforms observed in small rivers and laboratory experiments, and in which the downstream leeside angle is often assumed to be at the angle-of-repose. Here we show, using high-resolution bathymetry from a range of the worlds great rivers, that dunes are instead characterized predominantly by low-angle leeside slopes (

Citation

Cisneros, J., Best, J., van Dijk, T., Almeida, R. P. D., Amsler, M., Boldt, J., Freitas, B., Galeazzi, C., Huizinga, R., Ianniruberto, M., Ma, H., Nittrouer, J. A., Oberg, K., Orfeo, O., Parsons, D., Szupiany, R., Wang, P., & Zhang, Y. (2020). Dunes in the world’s big rivers are characterized by low-angle lee-side slopes and a complex shape. Nature Geoscience, 13(2), 156-162. https://doi.org/10.1038/s41561-019-0511-7

• Journal Article Type: Article
• Acceptance Date: Nov 20, 2019
• Online Publication Date: Jan 20, 2020
• Publication Date: 2020-02
• Deposit Date: Jan 20, 2020
• Publicly Available Date: Jul 21, 2020
• Journal: Nature Geoscience
• Print ISSN: 1752-0894
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 2
• Pages: 156-162
• DOI: https://doi.org/10.1038/s41561-019-0511-7
• Keywords: General Earth and Planetary Sciences
• Public URL: https://hull-repository.worktribe.com/output/3377630
• Publisher URL: https://www.nature.com/articles/s41561-019-0511-7