At the northern end of this road cutting, rocks belonging to the lower division of the Witwatersrand Supergroup consist of layers of hard quartzite and softer, red coloured siltstones, all of which dip southward at 60°. In the southern end of the cutting, and [unclear] to the uppermost division of the Witwatersrand Supergroup are hard quartzites with scattered pebbly layers or conglomerate dipping southeastwards at 35°. The two rock groups are juxtaposed because of movement along a break or fault. The fault itself is characterised by small dark fragments in a white matrix, called a breccia, and formed as a result of grinding of the rocks during movement along the fault.
Cressy Street, Kensington
Geological Society of South Africa