A general model for the helical structure of geophysical flows in channel bends

Azpiroz-Zabala, M.; Cartigny, M.J.B.; Sumner, E.J.; Clare, M.A.; Talling, P.J.; Parsons, D.R.; Cooper, C.

doi:10.1002/2017gl075721

A general model for the helical structure of geophysical flows in channel bends

Azpiroz-Zabala, M.; Cartigny, M.J.B.; Sumner, E.J.; Clare, M.A.; Talling, P.J.; Parsons, D.R.; Cooper, C.

Authors

M. Azpiroz-Zabala

Dr Matthieu Cartigny matthieu.j.cartigny@durham.ac.uk
Associate Professor

E.J. Sumner

M.A. Clare

Professor Peter Talling peter.j.talling@durham.ac.uk
Professor

D.R. Parsons

C. Cooper

Abstract

Meandering channels formed by geophysical flows (e.g. rivers and seafloor turbidity currents) include the most extensive sediment transport systems on Earth. Previous measurements from rivers show how helical flow at meander bends plays a key role in sediment transport and deposition. Turbidity currents differ from rivers in both density and velocity profiles. These differences, and the lack of field measurements from turbidity currents, have led to multiple models for their helical flow around bends. Here we present the first measurements of helical flow in submarine turbidity currents. These ten flows lasted for 1-to-10 days, were up to ~80-metres thick, and displayed a consistent helical structure. This structure comprised two vertically-stacked cells, with the bottom cell rotating with the opposite direction to helical flow in rivers. Furthermore, we propose a general model that predicts the range of helical flow structures observed in rivers, estuaries and turbidity currents based on their density stratification.

Citation

Azpiroz-Zabala, M., Cartigny, M., Sumner, E., Clare, M., Talling, P., Parsons, D., & Cooper, C. (2017). A general model for the helical structure of geophysical flows in channel bends. Geophysical Research Letters, 44(23), 11,932-11,941. https://doi.org/10.1002/2017gl075721

Journal Article Type	Article
Acceptance Date	Nov 21, 2017
Online Publication Date	Dec 11, 2017
Publication Date	Dec 16, 2017
Deposit Date	Oct 31, 2017
Publicly Available Date	Dec 8, 2017
Journal	Geophysical Research Letters
Print ISSN	0094-8276
Electronic ISSN	1944-8007
Publisher	Wiley
Peer Reviewed	Peer Reviewed
Volume	44
Issue	23
Pages	11,932-11,941
DOI	https://doi.org/10.1002/2017gl075721

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Copyright Statement
© 2017. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.