Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Flushing submarine canyons

Abstract

The continental slope is a steep, narrow fringe separating the coastal zone from the deep ocean. During low sea-level stands, slides and dense, sediment-laden flows erode the outer continental shelf and the continental slope, leading to the formation of submarine canyons that funnel large volumes of sediment and organic matter from shallow regions to the deep ocean1. During high sea-level stands, such as at present, these canyons still experience occasional sediment gravity flows2–5, which are usually thought to be triggered by sediment failure or river flooding. Here we present observations from a submarine canyon on the Gulf of Lions margin, in the northwest Mediterranean Sea, that demonstrate that these flows can also be triggered by dense shelf water cascading (DSWC)—a type of current that is driven solely by seawater density contrast. Our results show that DSWC can transport large amounts of water and sediment, reshape submarine canyon floors and rapidly affect the deep-sea environment. This cascading is seasonal, resulting from the formation of dense water by cooling and/or evaporation, and occurs on both high- and low-latitude continental margins6–8. DSWC may therefore transport large amounts of sediment and organic matter to the deep ocean. Furthermore, changes in the frequency and intensity of DSWC driven by future climate change may have a significant impact on the supply of organic matter to deep-sea ecosystems and on the amount of carbon stored on continental margins and in ocean basins.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Bathymetry maps and station location.
Figure 2: Time series and sections of key parameters in the CCC.
Figure 3: Deep comparative profiles of key parameters at and off the CCC mouth.
Figure 4: Acoustic image of the CCC floor.

References

  1. Posamentier, H. W., Jervey, M. T. & Vail, P. R. Eustatic controls on clastic deposition I – Conceptual framework. Soc. Econ. Paleontol. Miner. Spec. Publ. 42, 110–124 (1988)

    Google Scholar 

  2. Mulder, T., Weber, O., Anschutz, P., Jorissen, F. & Jouanneau, J. M. A few month-old storm generated turbidite deposited in the Capbreton Canyon (Bay of Biscay, SW France). Geo-Mar. Lett. 21, 149–156 (2001)

    Article  ADS  Google Scholar 

  3. Khripounoff, A. et al. Direct observation of intense turbidity current activity in the Zaire submarine valley at 4000 m depth. Mar. Geol. 194, 151–158 (2003)

    Article  ADS  CAS  Google Scholar 

  4. Paull, C. K. et al. Caught in the act: the 20 December 2001 gravity flow event in Monterey Canyon. Geo-Mar. Lett. 22, 227–232 (2003)

    Article  ADS  Google Scholar 

  5. Puig, P. et al. Storm-induced sediment gravity flows at the head of the Eel submarine canyon, northern California margin. J. Geophys. Res. 109 C03019 doi: 10.1029/2003JC001918 (2004)

    Article  ADS  Google Scholar 

  6. Whitehead, J. A. Dense water off continents. Nature 327, 656 (2002)

    Article  ADS  Google Scholar 

  7. Shapiro, G. I., Huthnance, J. M. & Ivanov, V. V. Dense water cascading off the continental shelf. J. Geophys. Res. 108 3390 doi: 10.1029/2002JC001610 (2003)

    Article  ADS  Google Scholar 

  8. Ivanov, V. V., Shapiro, G. I., Huthnance, J. M., Aleynik, D. L. & Golovin, P. N. Cascades of dense water around the world ocean. Progr. Oceanogr. 60, 47–98 (2004)

    Article  ADS  Google Scholar 

  9. Lacombe, H., Tchernia, P. & Gamberoni, L. Variable bottom water in the Western Mediterranean Basin. Progr. Oceanogr. 14, 319–338, doi:10.1016/00796611(85)90015-1. (1985)

    Article  ADS  Google Scholar 

  10. Durrieu de Madron, X., Zervakis, V., Theocharis, A. & Georgopoulos, D. Comments to "Cascades of dense water around the world ocean”. Progr. Oceanogr. 64, 83–90 (2005)

    Article  ADS  Google Scholar 

  11. Béthoux, J. P., Durrieu de Madron, X., Nyffeler, F. & Tailliez, D. Deep water in the western Mediterranean: peculiar 1999 and 2000 characteristics, shelf formation hypothesis, variability since 1970 and geochemical inferences. J. Mar. Sys. 33–34, 117–131 (2002)

    Article  Google Scholar 

  12. Lopez-Jurado, J. L., Gonzalez-Pola, C. & Velez-Belchi, P. Observation of an abrupt disruption of the long-term warming trend at the Balearic Sea, western Mediterranean Sea, in summer 2005. Geophys. Res. Lett. 32 L24606 doi: 10.1029/2005GL024430 (2005)

    Article  ADS  Google Scholar 

  13. Flood, R. D. Classification of sedimentary furrows and a model for furrows initiation and evolution. Geol. Soc. Am. Bull. 94, 630–639 (1983)

    Article  ADS  Google Scholar 

  14. Flood, R. D. Abyssal bedforms as indicators of changing bottom current flow: examples from the U.S. East Coast continental rise. Paleoceanography 9, 1049–1060 (1994)

    Article  ADS  Google Scholar 

  15. Dasgupta, P. Sediment gravity flow—the conceptual problems. Earth-Sci. Rev. 62, 265–281 (2003)

    Article  ADS  Google Scholar 

  16. Shapiro, G. I. & Hill, A. E. Dynamics of dense water cascades at the shelf edge. J. Phys. Oceanogr. 27, 2381–2394 (1997)

    Article  ADS  Google Scholar 

  17. Masson, D. G., Kenyon, N. H. & Weaver, P. P. E. in Oceanography: An Illustrated Guide (eds Summerhayes, C. P. & Thorpe, S. A.) 146–151 (Manson, London, 1996)

    Google Scholar 

  18. Honjo, S., Manganini, S. M. & Wefer, G. Annual particle flux and a winter outburst of sedimentation in the northern Norwegian Sea. Deep-Sea Res. A 35, 1223–1234 (1988)

    Article  ADS  Google Scholar 

  19. Yoder, J. & Ishimaru, T. Phytoplankton advection off the southeastern United States continental shelf. Cont. Shelf Res. 9, 547–553 (1989)

    Article  ADS  Google Scholar 

  20. Hill, A. E. et al. The Malin cascade in winter 1996. J. Mar. Res. 56, 87–106 (1998)

    Article  Google Scholar 

  21. Avril, B. DOC dynamics in the northwestern Mediterranean Sea (DYFAMED site). Deep-Sea Res. II 49, 2163–2182 (2002)

    Article  ADS  CAS  Google Scholar 

  22. Earth Resources Information Systems Data Center. Global 30 arc second elevation data set. <http://edcwww.cr.usgs.gov/landdaac/gtopo30/gtopo30.html> (1996)

  23. Somot, S., Sevault, F. & Deque, M. Transient climate change scenario simulation of the Mediterranean Sea for the twenty-first century using a high-resolution ocean circulation model. Clim. Dyn. doi: 10.1007/s00382-006-0167-z (published online, 20 July 2006)

  24. HoughtonJ. T.et al. Climate Change 2001: The Scientific Basis (Cambridge Univ. Press, Cambridge, 2001)

  25. Gregory, J. M. et al. A model intercomparison of changes in the Atlantic thermohaline circulation in response to increasing atmospheric CO2 concentration. Geophys. Res. Lett. 32 L12703 doi: 10.1029/2005GL023209 (2005)

    Article  ADS  CAS  Google Scholar 

  26. Tsunogai, S., Watanabe, S. & Sato, T. Is there a "continental shelf pump" for the absorption of atmospheric CO2? Tellus B 51, 701–712, doi: 10.1034/j.1600-0889.1999.t01-2-00010.x (1999)

    Article  ADS  Google Scholar 

  27. Cauwet, G. HTCO method for dissolved organic carbon analysis in sea water: influence of catalyst on black estimation. Mar. Chem. 47, 55–64 (1994)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This work was supported by the European Commission (EUROSTRATAFORM, EURODOM and HERMES projects), the Office of Naval Research, CNRS-INSU and the Catalan Government. Sediment cohesion data were provided by N. Sultan, N data by T. Tesi, and DOC data by M. Pujo-Pay. Multibeam bathymetry was collected in cooperation with Fugro Survey Ltd and AOA Geophysics. Contributions of the scientific and technical staff at the authors’ home institutions are warmly acknowledged. Author Contributions All authors contributed to the design and implementation of the experimental strategy. M.C. steered the integration and joint analysis of the data, interpreted side scan sonar data and wrote the final version of the paper in cooperation with S.H. P.P., X.D.d.M. and A.P. took the responsibility for time series, X.D.d.M. for hydrology data, and S.H. and J.F. for sediment trap data. All authors discussed the results and commented on the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Miquel Canals.

Ethics declarations

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Supplementary information

Supplementary Notes

This file contains Supplementary Methods and Supplementary Figure Legends. (DOC 30 kb)

Supplementary Figure 1

Long term records from the Lacaze-Duthiers Canyon since October 1993. (PDF 21902 kb)

Supplementary Figure 2

Time integrated along-canyon cumulative suspended sediment transport for seven submarine canyons in the Gulf of Lion. (PDF 80 kb)

Supplementary Figure 3

Near-bottom time series of potential temperature, potential density anomaly, current speed and suspended sediment concentration. (PDF 219 kb)

Supplementary Figure 4

Time series before cascading (a) and during cascading (b) in winter 2004-05. (PDF 105 kb)

Supplementary Figure 5

C/N regression fit for trap particles collected in the Cap de Creus and Lacaze-Duthiers canyons during autumn stratified conditions and DSWC events. (PDF 126 kb)

Supplementary Figure 6

Coastal regions in the world where DSWC has been observed. (PDF 1110 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Canals, M., Puig, P., de Madron, X. et al. Flushing submarine canyons. Nature 444, 354–357 (2006). https://doi.org/10.1038/nature05271

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature05271

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing