Transport of Fine Sediment with Mesoscale Currents
in the ShelfSlope Zone of the Sea

G. I. Shapiro, T. M. Akivis, N. V. Pykhov, and S. M. Antsyferov

Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia

Received December 28, 1998

Abstract—We developed a semianalytical model of the transport of fine suspended material with mesoscale
currents in the near-bottom boundary layer in the shelf–slope zone of the ocean. With this model, the vertical
profiles of the horizontal velocity and concentration of suspended material are calculated analytically in a quasi-
one-dimensional approximation. The profiles obtained are used for calculations of the horizontal suspended
matter fluxes. An integral advection–diffusion equation is deduced for describing the balance of suspended
material in the near-bottom layer. The equation is solved numerically. The sedimentary material is assumed to
be weakly consolidated. The model can be employed for the calculation of the transport of fine suspended material
with various mesoscale currents, such as cyclonic and anticyclonic eddies, as well as by meandering longshore
currents. It is shown that due to the strong nonlinearity of the problem, small variations in the intensity of a
current result in significant variations in the rate of sedimentation and erosion. Because of the onset of the sec-
ondary circulation in the near-bottom Ekman’s layer, the direction of the suspension transport and the direction
of the current in the water thickness are not the same. It is shown that mesoscale eddies moving along the con-
tinental slope form elongated zones of erosion and sedimentation in the direction of their propagation. This
mechanism allows the matter to be transported both up and down to the continental slope.

Pleiades Publishing home page | journal home page | top

If you have any problems with this server, contact webmaster.