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Sediment Transport Along the Cap De Creus Canyon Flank During a Mild, Wet Winter : Volume 9, Issue 12 (14/12/2012)

By Martín, J.

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Book Id: WPLBN0003984730
Format Type: PDF Article :
File Size: Pages 42
Reproduction Date: 2015

Title: Sediment Transport Along the Cap De Creus Canyon Flank During a Mild, Wet Winter : Volume 9, Issue 12 (14/12/2012)  
Author: Martín, J.
Volume: Vol. 9, Issue 12
Language: English
Subject: Science, Biogeosciences, Discussions
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2012
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

Citation

APA MLA Chicago

De Madron, X. D., Houpert, L., Canals, M., Palanques, A., Bourrin, F., Calafat, A. M.,...Sanchez-Vidal, A. (2012). Sediment Transport Along the Cap De Creus Canyon Flank During a Mild, Wet Winter : Volume 9, Issue 12 (14/12/2012). Retrieved from http://www.ebooklibrary.org/


Description
Description: Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta 37–49, 08003, Barcelona, Spain. Cap de Creus Canyon (CCC) is known as a preferential conduit for particulate matter leaving the Gulf of Lion continental shelf towards the slope and the deep basin, particularly in winter when storms and dense shelf water cascading coalesce to enhance the seaward export of shelf waters.

During the CASCADE (CAscading, Storm, Convection, Advection and Downwelling Events) cruise in March 2011, deployments of recording instruments within the canyon and vertical profiling of the water column properties were conducted to study with high spatial-temporal resolution the impact of such processes on particulate matter fluxes.

In the context of a mild and wet 2010–2011 winter, no remarkable dense shelf water formation was observed. On the other hand, the experimental setup allowed to study the impact of E-SE storms on the hydrographical structure and the particulate matter fluxes in the CCC. The most remarkable feature in terms of sediment transport was a period of dominant E-SE winds from 12 to 16 March, including two moderate storms of significant wave heights = 4–4.5 m. During this period, a plume of freshened, relatively cold and turbid water flowed at high speeds along the southern flank of CCC in an approximate depth range of 150–350 m. The density of this water mass only reached ~ 28.78 kg m−3, indicating that it did not cascade into the canyon and that merely downwelled into it forced by the accumulation of seawater along the coast during the storms and by the subsequent strong cyclonic circulation induced over the shelf. Suspended sediment load in this turbid intrusion was comparable at three heights above bottom where turbidimeters were installed (10, 75 and 115 m above bottom) on the southern canyon flank and oscillated between 10 and 50 mg L−1. Current speeds were also comparable in the depth range profiled by ADCPs (40 to 150 mab) and reached values up to 90 cm s−1 during the peak of the strongest storm (13 March, Hs = 4.5 m).

Sediment transport at 75 mab on the southern canyon flank was estimated at 1–1.5 t m−2 for the entire deployment while very close to the bottom (5 m above) in the canyon head it was less than 0.6 t m−2 during the same period. We provide a rough estimation of 105 t of sediment transported through the canyon along its southern wall during a 3 day-long period of storm-induced downwelling.

Following the veering of the wind direction (from SE to NW) on 16 March, downwelling ceased, currents inside the canyon reversed from down to up-canyon, and the turbid shelf plume was evacuated from the canyon, most probably flowing along the southern canyon flank and being entrained by the general SW circulation after leaving the canyon confinement.

This study highlights that remarkable sediment transport occurs in the CCC, and particularly along its southern flank, even during mild and wet winters, in absence of cascading and under limited external forcing. The sediment transport associated to eastern storms like the ones described in this paper tends to enter the canyon by its downstream flank, partially affecting the canyon head region. Sediment transport during these events is not constrained near the seafloor but distributed in a depth range of 200–300 m above the bottom. Our paper broadens the understanding of the complex set of atmosphere-driven sediment transport processes acting in this highly dynamic area of the northwestern Mediterranean Sea.


Summary
Sediment transport along the Cap de Creus Canyon flank during a mild, wet winter

Excerpt
Allen, S. E. and Durrieu de Madron, X.: A review of the role of submarine canyons in deep-ocean exchange with the shelf, Ocean Sci., 5, 607–620, doi:10.5194/os-5-607-2009, 2009.; Bonnin, J., Heussner, S., Calafat, A., Fabres, J., Palanques, A., Durrieu de Madron, X., Canals, M., Puig, P., Avril, J., and Delsaut, N.: Comparison of horizontal and downward particle fluxes across canyons of the Gulf of Lions (NW Mediterranean): Meteorological and hydro dynamical forcing, Cont. Shelf Res., 28, 1957–1970, 2008.; Bougis, P. and Ruivo, M.: Sur une descente des eaux superficielles en profondeur (cascading) dans le sud du Golfe du Lion, Bulletin d'Information du Comité Central d'Océanographie et d'Etude des Côtes, 6, 147–154, 1954.; Bourrin, F., Durrieu de Madron, X., and Ludwig, W.: Contribution to the study of coastal rivers and associated prodeltas to sediment supply in the Gulf of Lions, Life Environ., 56, 307–314, 2006.; Bourrin, F., Durrieu de Madron, X., Heussner, S., and Estournel, C.: Impact of winter dense water formation on shelf sediment erosion (evidence from the Gulf of Lions, NW Mediterranean), Cont. Shelf Res., 28, 1984–1999, 2008.; Bourrin, F., Durrieu de Madron, X., Beguery, L., Martín, J., and Houpert, L.: Sediment resuspension and fluxes estimated from glider during a typical winter storm in the Gulf of Lions, NW Mediterranean, in preparation, 2012.; Buscail, R. and Germain, C.: Present-day organic matter sedimentation on the NW Mediterranean margin: Importance of off-shelf export, Limnol. Oceanogr., 42, 217–229, 1997.; Canals, M., Puig, P., Durrieu de Madron, X., Heussner, S., Palanques, A., and Fabres, J.: Flushing submarine canyons, Nature, 444, 354–357, 2006.; DeGeest, A. L., Mullenbach, B. L., Puig, P., Nittrouer, C. A., Drexler, T. M., Durrieu de Madron, X., and Orange, D. L.: Sediment accumulation in the western Gulf of Lions, France: The role of Cap de Creus Canyon in linking shelf and slope sediment dispersal systems, Cont. Shelf Res., 28, 2031–2047, 2008.; Dewey, R. K.: Mooring Design & Dynamics – a Matlab® package for designing and analyzing oceanographic moorings, Mar. Models, 1, 103–157, 1999.; DREAL: http://www.languedoc-roussillon.developpement-durable.gouv.fr/IMG/pdf/DREAL_LR-rapport_coup_de_mer_12-16_mars_2011_cle5d39f7.pdf., 2011.; Drexler, T. M. and Nittrouer, C. A.: Stratigraphic signatures due to flood deposition near the Rhône River: Gulf of Lions, northwest Mediterranean Sea, Cont. Shelf Res., 28, 1877–1894, 2008.; Dufau-Julliand, C., Marsaleix, P., Petrenko, A., and Dekeyser, I.: Three-dimensional modeling of the Gulf of Lion's hydrodynamics (north-west Mediterranean) during January 1999 (MOOGLI3 Experiment) and late winter 1999: Western Mediterranean Intermediate Water's (WIW's) formation and its cascading over the shelf break, J. Geophys. Res., 109, C11002, doi:10.1029/2003JC002019, 2004.; Durrieu de Madron, X., Zervakis, V., Theocharis, A., and Georgopoulos, D.: Comments on Cascades of dense water around the world ocean, Prog. Oceanogr., 64, 83–90, 2005.; Durrieu de Madron, X., Wiberg, P. L., and Puig, P.: Sediment dynamics in the Gulf of Lions: The impact of extreme events, Cont. Shelf Res., 28, 1867–1876, 2008.; Ferré, B., Guizien, K., Durrieu de Madron, X., Palanques, A., Guillén, J., and Grémare, A.: Fine sediment dynamics study during a winter storm in the Gulf of Lion shelf (NW Mediterranean), Cont. Shelf Res., 25, 2410–2427, 2005.; Firing, E. and Hummon, J. M.: Ship-mounted Acoustic Doppler Current Profilers, in: The GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines, edited by: Hood, E. M., Sabine,C. L., and Sloyan, B. M., IOCCP Report Number 14, ICPO Publication

 

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