SEDIMENT TRANSPORT DUE TO CURRENT-SUPPORTED TURBIDITY CURRENTS OVER AN ERODIBLE BED
AbstractWave- and current-supported turbidity currents (WCSTCs), are one of the chief participants in shaping the marine geomorphology. What makes WCSTCs different from other turbidity currents is that boundary layer turbulence is required to suspend the sediments rather than the self-motion of the turbidity currents. In the presence of a mild slope, the gravitational acceleration drives the suspended sediments offshore (Sternberg et al., 1996; Wright et al., 2001). Depending on what dominates the boundary layer turbulence (BLT), we further define two major subclasses of WCSTCs: (i) wave-supported (WSTCs), and (ii) current-supported turbidity currents (CSTCs). Although significant advances have been made on the details of WSTCs (Ozdemir et al., 2011; Yu et al., 2014; Cheng et al., 2015), less is known about CSTCs. The objective of present study is to investigate the role of alongshore currents on CSTC dynamics over an erodible bottom boundary. The focus here is to identify the possible role of erosion on CSTC dynamics, and assess the coupling between current-induced BLT and suspended sediments for various bed erodibility parameters, i.e. critical shear stress, erosion coefficient, and settling velocity.
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