Tidal propagation over fluid mud layers on the Amazon shelf

摘要: Abstract Dense layers of suspended fine sediments (concentrations the order 10 1 –10 2  g l −1 ) have been observed within lower ∼2–4 m water column on Amazon continental shelf. The presence these fluid mud leads to an increase in viscosity and density, has suggested reduce bottom shear stress, thus affecting tidal wave propagation. This work presents a numerical study effects upon flow A two dimensional, vertically integrated, finite element model configured region, for simulating propagation M component. Bottom stress over is parameterized based viscous oscillatory boundary layer model, while sand consolidated beds computed with classical turbulent parameterization. Simulations which shelf considered consist only sand, or muds, significantly underestimate amplitudes along coast. Otherwise, if taken into account, distribution derived from previous observations, are well represented by model. results demonstrate that near-bottom represent important factor dynamics shelf, since reducing and, therefore, lowering energy dissipation, larger allowed occur.