Data/hora: 01/06/2024 10:18:21

Provedor de dados: | 5
País: | France
Título: | Direct monitoring reveals initiation of turbidity currents from extremely dilute river plumes
Autores: | Hage, Sophie; Cartigny, Matthieu J.b.; Sumner, Esther J.; Clare, Michael A.; Hughes Clarke, John E.; Talling, Peter J.; Lintern, D. Gwyn; Simmons, Stephen M.; Silva Jacinto, Ricardo; Vellinga, Age J.; Allin, Joshua R.; Azpiroz‐zabala, Maria; Gales, Jenny A.; Hizzett, Jamie L.; Hunt, James E.; Mozzato, Alessandro; Parsons, Daniel R.; Pope, Ed L.; Stacey, Cooper D.; Symons, William O.; Vardy, Mark E.; Watts, Camilla.
Data: | 2019-10
Ano: | 2019
Resumo: | Rivers (on land) and turbidity currents (in the ocean) are the most important sediment transport processes on Earth. Yet, how rivers generate turbidity currents as they enter the coastal ocean remains poorly understood. The current paradigm, based on laboratory experiments, is that turbidity currents are triggered when river plumes exceed a threshold sediment concentration of ~1 kg.m‐3. Here we present direct observations of an exceptionally dilute river‐plume, with sediment concentrations one order of magnitude below this threshold (0.07 kg.m‐3), which generated a fast (1.5 m.s‐1), erosive, short‐lived (6 min) turbidity current. However, no turbidity current occurred during subsequent river‐plumes. We infer that turbidity currents are generated when fine‐sediment, accumulating in a tidal turbidity maximum, is released during spring tide. This means that very dilute river‐plumes can generate turbidity currents more frequently and in a wider range of locations, than previously thought.
Tipo: | Text
Idioma: | Inglês

Identificador:

https://archimer.ifremer.fr/doc/00514/62594/66952.pdf

https://archimer.ifremer.fr/doc/00514/62594/66954.pdf

DOI:10.1029/2019GL084526

https://archimer.ifremer.fr/doc/00514/62594/

Editor: | American Geophysical Union (AGU)
Formato: | application/pdf
Fonte: | Geophysical Research Letters (0094-8276) (American Geophysical Union (AGU)), 2019-10 , Vol. 46 , N. 20 , P. 11310-11320

Fonte:

info:eu-repo/semantics/openAccess

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