Frequency dependent cross-shore suspended sediment ransport. 1. A nonbarred shoreface

Osborne, P.D. and Greenwood, B., 1992. Frequency dependent cross-shore suspended sediment transport. 2. A barred shore-face. Mar. Geol., 106: 25-51. Field measurements of the local time-varying suspended sediment flux across a barred shoreface demonstrate hat sediment transport is a response to high frequency wind wave oscillatory currents, low frequency waves and mean flows. The relative importance of the various transport components varies spatially and temporally in association with variability in the incident wave energy. In contrast o the non-barred shoreface, where variations were strongly depth-dependent, sediment transport across the barred shoreface is constrained by position with respect o the bars. On the lakeward slope of the bar, wind-wave oscillatory currents induce large rates of onshore transport near the bed; low frequency oscillatory currents (< 0.05 Hz) in this region are driven by the group-forced, bound long wave and produce an offshore transport, often equal in magnitude to that induced by the wind waves. The sediment transport attributable to mean currents near the bed is always offshore, resulting in a net offshore sediment flux across the slope. On the bar crest, net sediment transport is seen to be close to zero, owing to a balance between the offshore mean transport and the onshore net oscillatory transport (resulting from interaction between both high and low frequency waves). Landward of the bar crest and in the trough, sediment transport by wind waves decreases owing to dissipation of energ