Shorefaces

The shoreface is a seaward sloping, sandstone depositional wedge, and can be subdivided into a lower, middle, and upper shoreface. The sediment wedge grades basinward into offshore sandy and silty shales and landward into foreshore sandstones and/or conglomerates. The lower shoreface lies within fair-weather wave base. The trace-fossil assemblages typically reflect a diverse and abundant Cruziana Ichnofacies. The middle shoreface contains swaley and lesser hummocky cross-stratified sandstones with a trace-fossil assemblage dominated by the Skolithos Ichnofacies. The upper shoreface is dominated by multidirectional trough cross-bedding. Trace fossils are rarely abundant and consist of deeply penetrating structures of the Skolithos Ichnofacies. Under exceedingly high-energy conditions, Macaronichnus may be developed near the transition with the foreshore. Shoreface successions display a wide range of variability, largely restricted to the lower and middle shoreface intervals. This variability appears to be controlled by relative storm dominance and the episodic nature of associated storm-bed deposition.