Sediment-Driven Downslope Flow in Submarine Canyons and Channels: Three-Dimensional Numerical Experiments

Jochen Kämpf Institut für Meereskunde der Universität Hamburg, Hamburg, Germany

Search for other papers by Jochen Kämpf in
Current site
Google Scholar
PubMed
Close
and
Hermann Fohrmann Christian-Albrechts-Universität zu Kiel, Kiel, Germany

Search for other papers by Hermann Fohrmann in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

The role of submarine canyons and channels in sediment-driven downslope flow (sediment plumes) is examined, using a three-dimensional, rotational numerical model that couples the hydrodynamics and sediment transport. The model domain consists of a bottom ocean layer of constant height coupled with an essentially inert upper ocean. The model equations are cast in a rotated, bottom-following coordinate system in which vertical grid spacing is independent of the ocean depth and bathymetry can be resolved accurately. This allows for tracing bottom-attached sediment plumes (∼decameters in height) from shallow water into great depths of the ocean. The calculations reproduce morphologic features related to the occurrance of sediment plumes, such as the formations of 1) localized deposition areas of sediment off the mouth of submarine canyons and 2) levees at both sides of submarine channels. Furthermore, it is demonstrated that sediment plumes are not only important for the transport of littoral sediment to deeper water, but also trigger renewal of deep water, as being observed in a tropical ocean. Sediment plumes, predicted here, are short-lived, transient features with lifetimes of days and velocities of up to 90 cm s−1.

* Current affiliation: School of Earth Sciences, Flinders University, Adelaide, Australia.

Corresponding author address: Jochen Kämpf, School of Earth Sciences, Flinders University of South Australia, G.P.O. Box 2100, Adelaide 5001 SA, Australia.

jochen.kaempf&commatƒinders.edu.au

Abstract

The role of submarine canyons and channels in sediment-driven downslope flow (sediment plumes) is examined, using a three-dimensional, rotational numerical model that couples the hydrodynamics and sediment transport. The model domain consists of a bottom ocean layer of constant height coupled with an essentially inert upper ocean. The model equations are cast in a rotated, bottom-following coordinate system in which vertical grid spacing is independent of the ocean depth and bathymetry can be resolved accurately. This allows for tracing bottom-attached sediment plumes (∼decameters in height) from shallow water into great depths of the ocean. The calculations reproduce morphologic features related to the occurrance of sediment plumes, such as the formations of 1) localized deposition areas of sediment off the mouth of submarine canyons and 2) levees at both sides of submarine channels. Furthermore, it is demonstrated that sediment plumes are not only important for the transport of littoral sediment to deeper water, but also trigger renewal of deep water, as being observed in a tropical ocean. Sediment plumes, predicted here, are short-lived, transient features with lifetimes of days and velocities of up to 90 cm s−1.

* Current affiliation: School of Earth Sciences, Flinders University, Adelaide, Australia.

Corresponding author address: Jochen Kämpf, School of Earth Sciences, Flinders University of South Australia, G.P.O. Box 2100, Adelaide 5001 SA, Australia.

jochen.kaempf&commatƒinders.edu.au

Save
  • Aagaard, K., J. H. Swift, and E. C. Carmack, 1985: Thermohaline circulation in the Arctic mediterranean seas. J. Geophys. Res.,90, 4833–4846.

  • Adams, C. E., 1981: Some effects of suspended sediment stratification on an oceanic bottom boundary layer. J. Geophys. Res.,86, 4161–4172.

  • Allen, J. R. L., 1994: Fundamental properties of fluids and their relation to sediment transport processes. Sediment Transport and Depositional Processes, S. J. Pye, Ed., Blackwell Science, 25– 60.

  • Backhaus, J. O., H. Fohrmann, J. Kämpf, and A. Rubino, 1997: Formation and export of water masses produced in Arctic shelf polynyas. ICES-J. Mar. Sci.,54, 366–382.

  • Baines, P. G., and S. Condie, 1998: Observations and modelling of Antarctic downslope flows: A review. Ocean, Ice and Atmosphere: Interactions at the Continental Margin, Antarctic Research Series, S. S. Jakobs and R. Weiss, Eds., Vol. 15, Amer. Geophys. Union, 29–49.

  • Blaume, F., 1992: Hochakkumulationsgebiet am norwegischen Kontinentalhang: Sedimentologische Abbilder topographie-geführter Strömungsmuster. Rep. SFB 313, Vol. 36, University of Kiel, 177 pp. [Available from Christian-Albrechts-Universität zu Kiel, Heinrich-Hecht-Platz 10, D-24118 Kiel, Germany.].

  • Blumberg, A. F., and G. L. Mellor, 1980: A coastal ocean numerical model. Mathematical Modelling of Estuarine Physics: Proceedings of an International Symposium, J. S&uuml–ermann and K.-P. Holtz, Eds., Springer-Verlag, 203–214.

  • ——, and ——, 1987: A description of a three-dimensional coastal ocean circulation model. Three-Dimensional Coastal Ocean Models, N. Heaps, Ed., Coastal Estuarine Science Series, Vol. 4, Amer. Geophys. Union, 1–16.

  • Bonnecaze, R. T., H. E. Huppert, and J. R. Lister, 1993: Particle-driven gravity currents. J. Fluid Dyn.,250, 339–369.

  • ——, M. A. Hallworth, H. E. Huppert, and J. R. Lister, 1995: Axissymmetric particle-driven gravity currents. J. Fluid Dyn.,294, 93–121.

  • Brugge, R., H. L. Jones, and J. C. Marshall, 1991: Nonhydrostatic ocean modeling for studies of open-ocean deep convection. Deep Convection and Deep Water Formation, P. E. Chu and G. C. Gascard, Eds., Elsevier, 325–340.

  • Carey, S. N., H. Sigurdson, and R. S. J. Sparks, 1988: Experimental studies of particle-laden plumes. J. Geophys. Res.,93, 15314– 15328.

  • Chao, S.-Y., 1998: Hyperpycnal and buoyant plumes from a sediment-laden river. J. Geophys. Res.,103, 3067–3081.

  • Chapman, D. C., and G. Gawarkiewicz, 1995: Offshore transport of dense shelf water in the presence of a submarine canyon. J. Geophys. Res.,100, 13373–13387.

  • Emery, K. O., J. Hülsemann, and K. S. Rodolfo, 1962: Influence of turbidity currents upon basin waters. Limnol. Oceanogr.,7 (4), 439–446.

  • Ezer, T., and G. L. Weatherly, 1990: A numerical study of the interaction between a deep cold jet and a bottom boundary layer in the ocean. J. Phys. Oceanogr.,20, 801–816.

  • Fohrmann, H., J. O. Backhaus, F. Blaume, and J. Rumohr, 1998: Sediments in bottom arrested gravity plumes: Numerical case studies. J. Phys. Oceanogr.,28, 2250–2274.

  • Garcia, M., and G. Parker, 1993: Experiments on the entrainment of sediments into suspension by a dense bottom current. J. Geophys. Res.,98, 4793–4807.

  • Hamblin, P. F., 1989: Observations and model of sediment transport near the turbidity maximum of the upper Saint Lawrence estuary. J. Geophys. Res.,94, 14419–14428.

  • Heezen, H. W., and M. Ewing, 1952: Turbidity currents and submarine slumps and the Grand Banks earthquake. Amer. J. Sci.,250, 849–873.

  • Hollender, F.-J., 1996: Untersuchung des ostgrönländischen Kontinentalrandes mit dem Weitwinkel-Seitensicht-Sonar GLORIA. Rep. SFB 313, Vol. 67, University of Kiel, 124 pp. [Available from Christian-Albrechts-Universität zu Kiel, Heinrich-Hecht-Platz 10, D-24118 Kiel, Germany.].

  • Hübscher, C., V. Spieß, M. Breitzke, and M. E. Weber, 1997: The youngest channel-levee system of the Bengal Fan: Results from digital sediment echosounder data. Mar. Geol.,141, 125–145.

  • Jungclaus, J. H., and J. O. Backhaus, 1994: Application of a transient, reduced-gravity plume model to the Denmark Strait overflow. J. Geophys. Res.,99, 12375–12396.

  • Kämpf, J., and J. O. Backhaus, 1998: Shallow, brine-driven free convection in polar oceans: Nonhydrostatic numerical process studies. J. Geophys. Res.,103, 5577–5593.

  • ——, ——, and H. Fohrmann, 1999: Sediment-induced slope convection: Two-dimensional numerical case studies. J. Geophys. Res.,104, 20509–20522.

  • Kerr, R. C., 1991: Erosion of stable density gradient by sedimentation-driven convection. Nature,353, 423–425.

  • Klinger, B. A., J. Marshall, and U. Send, 1996: Representation of convective plumes by vertical adjustment. J. Geophys. Res.,101, 18175–18182.

  • Kochergin, V. P., 1987: Three-dimensional prognostic models. Three-Dimensional Coastal Ocean Models, N. S. Heaps, Ed., Coastal Estuarine Science Series, Vol. 4, Amer. Geophys. Union, 201– 208.

  • Kuijper, C., J. M. Cornelisse, and J. C. Winterwerp, 1989: Research on erosive properties of cohesive sediments. J. Geophys. Res.,94, 14341–14350.

  • Laval, A., M. Cremer, P. Beghin, and C. Ravenne, 1988: Density surges: Two-dimensional experiments. Sedimentology,35, 70– 84.

  • Macdonald, R. W., and D. J. Thomas, 1991: Chemical interactions and sediments of the western Canadian Arctic Shelf. Contin. Shelf Res.,11, 843–863.

  • Marshall, J., and F. Schott, 1999: Open-ocean convection: Observations, theory, and models. Rev. Geophys.,37, 1–64.

  • McCave, I. N., 1986: Local and global aspects of the bottom nepheloid layers in the world ocean. Netherlands J. Sea Res.,20, 167– 181.

  • Mellor, G. L., and A. F. Blumberg, 1985: Modeling vertical and horizontal diffusivities with the sigma coordinate system. Mon. Wea. Rev.,113, 1380–1383.

  • Menard, H. W., 1964: Marine Geology of the Pacific. McGraw-Hill, 271 pp.

  • Mesinger, F., and A. Arakawa, 1976: Numerical Methods Used in Atmospheric Models. Vol. 1, No. 17, GARP Publ. Series, WMO– ICSU, 63 pp.

  • Oey, L.-Y., G. L. Mellor, and R. I. Hires, 1985: A three-dimensional simulation of the Hudson-Raritan estuary, 1, Description of the model and model simulation. J. Phys. Oceanogr.,15, 1676– 1692.

  • Pantin, H. M., 1998: Laboratory demonstration of autosuspension. Abstracts, Conf. on Sediment Transport and Deposition by Particulate Gravity Currents, Leeds, United Kingdom, University of Leeds. [Available from School of Earth Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom.].

  • Parker, G., Y. Fukushima, and H. M. Pantin, 1986: Self-accelerating turbidity currents. J. Fluid Mech.,171, 145–181.

  • ——, ——, M. Garcia, and W. Yu, 1987: Experiments on turbidity currents over an erodible bed. J. Hydraulic Res.,25, 123–147.

  • Phillips, N. A., 1957: A coordinate system having some special advantages for numerical forecasting. J. Meteor.,14, 184–185.

  • Quadfasel, D., H. Kudrass, and A. Frische, 1990: Deep-water renewal by turbidity currents in the Sulu Sea. Nature,343, 320–322.

  • Rao, R. B. S., and Coauthors, 1998: Glimpses of Bengal Fan valleys off Andhra Pradesh and Tamil Nadu coasts. Mar. Wing Newsletters, Geol. Survey of India, Vol. 14, No. 1, p. 5.

  • Rudels, B., and D. Quadfasel, 1991: Convection and deep water formation in the Arctic Ocean–Greenland Sea system. J. Mar. Syst.,2, 435–450.

  • Sparks, R. S. J., R. T. Bonnecaze, H. E. Huppert, J. R. Lister, M. A. Hallworth, M. Harder, and J. Phillips, 1993: Sediment-laden gravity currents with reversing buoyancy. Earth Planet. Sci. Lett.,114, 243–257.

  • Stacey, M. W., and A. J. Bowen, 1988a: The vertical structure of density and turbidity currents: Theory and observations. J. Geophys. Res.,93, 3528–3542.

  • ——, and ——, 1988b: The vertical structure of turbidity currents and a necessary condition for self-maintenance. J. Geophys. Res.,93, 3543–3553.

  • Steele, M., and T. Boyd, 1998: Retreat of the cold halocline layer in the Arctic ocean. J. Geophys. Res.,103, 10419–10435.

  • Stow, D. A. V., 1994: Deep sea processes of sediment transport and deposition. Sediment Transport and Depositional Processes, K. Pye, Ed., Blackwell Science, 257–291.

  • Turner, J. S., 1973: Buoyancy Effects in Fluids. Cambridge University Press, 367 pp.

  • Weatherly, G. L., and P. J. Martin, 1978: On the structure and dynamics of the oceanic bottom boundary layer. J. Phys. Oceanogr.,8, 557–570.

  • Weingartner, T. J., D. J. Cavalieri, K. Aagaard, and Y. Sasaki, 1998:Circulation, dense water formation, and outflow on the northeast Chukchi shelf. J. Geophys. Res.,103, 7647–7661.

  • Zeng, J., and D. R. Lowe, 1997: Numerical simulation of turbidity current flow and sedimentation, 1, Theory. Sedimentology,44, 67–84.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 324 63 12
PDF Downloads 133 36 9