You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
On the Mechanics of Lutoclines and Fluid Mud
Mark A. Ross and Ashish J. Mehta
Journal of Coastal Research
SPECIAL ISSUE NO. 5. High Concentration Cohesive Sediment Transport (SUMMER 1989), pp. 51-62
Published by: Coastal Education & Research Foundation, Inc.
Stable URL: http://www.jstor.org/stable/25735365
Page Count: 12
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
The need to predict cohesive sediment transport rates in estuaries requires that the characteristics of the vertical suspension profile including lutocline and fluid mud layers be quantitatively understood. Cohesive sediment suspensions behave as stratified flows with mixing non-linearly dependent on concentration gradient. Additional complexity arises from the non-linear setting velocity dependence on concentration. Lutoclines form and persist in local regions of vertical diffusive flux minima. Near-bed fluid mud layers develop from rapid bed erosion or suspension deposition rates relative to upward mixing fluxes. The upper interface of the fluid mud layer, also a lutocline, represents a local maximum in the net (sum of settling and diffusion) downward settling flux. The lower fluid mud/bed interface, defined on the basis of soil mechanical properties, is in general quite different from the zero velocity plane. This because the zero velocity plane is very sensitive to the time histories of the hydrodynamic and rheological properties of the suspension, while the bed level is primarily dependent on the degree of consolidation and stress loading.
Journal of Coastal Research © 1989 Coastal Education & Research Foundation, Inc.