Just look at that sloughing slab! Was there ever a more open invitation for lobbing some plugs? I'd be hard pressed to find one. Here, in the stormy season, when conditions are perfect, slipfaces can slough slabs. A slab is a feature of the deep sand of the leeward slope. Sand, blown from the stoss, settles away from the wind, sometimes tumbling down a slipface. The stronger the wind, and the steeper the slope, the deeper these areas become. If a large wind event is followed by the right amount of rain, the uppermost sand will be wetted, with the lower portions being dry. The cohesion between water and sand will forms a crust, which, if deep enough, can be called a slab.
A slab sloughs primarily on the slipface. Here, there is the deepest layer of dry, loose, sand. While wetted sand is quite rigid, the drier sand beneath it settles, leaving a gap between it and the slab. When the force of gravity overwhelms the force of cohesion, the slab cracks and sloughs down the surface of the slipface. A brilliant feature.
While this shot is certainly not the most challenging, it is a joy to play into.
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