Stackpole Fault

The Stackpole Fault exposed in a small cove at Stackpole Quay, Pembrokeshire. The camera location of the previous photo in the photostream was in the notch at the top of the photo.

Jan is standing just to the left of the fault plane, which consists of a jumbled smash-zone of fragmented limestone recemented with calcite. To the left of the fault plane, the rocks are dipping northwards at about 45°. There is a well-developed, nearly vertical set of fractures (parallel to Jan). These are axial planar cleavage developed around the Stackpole Quay anticline, but have probably been amplified as pinnate cleavage by the proximity and movement of the Stackpole Fault. (A bit like trying to plane a piece of wood against the grain - the plane 'chatters' and you get a rough surface, not a smooth one)