Disturbance of the surface of Minnipa Hill Southeast, a low granite dome located on the northwestern Eyre Peninsula, on 19 January 1999, coincided with a shallow earth tremor, and it is suggested that the two events are causally related. The disturbance, which affected an area 170X100 m, took the form of rock bursts, reverse fault scarps, low angle planes of dislocation and overriding sheets, A-tents, dislocated slabs and blocks and widespread surficial flaking. Evidence of two earlier disturbances was noted. The event directly confirms the association of A-tents and dislocated slabs with compressive stress and by implication links bornhardts and sheet fractures with similar strain environments.

You do not currently have access to this article.