Three zones of thrust faulting, each zone with its own structural characteristics, have been identified in rocks of the Palaeozoic Table Mountain Group, just south of Uniondale, in the Cape Fold Belt. From north to south these zones consist of (1) shallow dipping sets of thrusts spaced, on average 10 m apart, (2) closely spaced (average 4 m apart) moderate to steeply-dipping thrusts associated with mesofolds, and (3) a zone mainly of backthrusts, spaced on average 2 m apart. All three zones formed during a single compressional event which took place during the Late Palaeozoic. Thrusting is interpreted to have commenced in zone (1) where thrusts developed in a break-back sequence, followed by thrusting in zones (2) and (3) where fore- and backthrusting were probably coeval. Upright fold structures in zone (2) controlled the steep orientation of thrust planes in this zone. The intensity of thrusting is so great that the 'Cedarberg Shale Formation', generally regarded as a regionally reliable stratigraphic marker in the Cape Fold Belt, has been eliminated in the study area. In addition, the scale of deformation seen locally in all units of the Table Mountain Group brings into sharp focus potential problems in respect of the recognition, thicknesses and correlation of lithostratigraphical units in the Cape Fold Belt. (C) 1999 Elsevier Science Limited. All rights reserved.
