THE VREDEFORT STRUCTURE - A PERSPECTIVE WITH REGARD TO NEW TECTONIC DATA FROM ADJOINING TERRANES

The deformational history of the area surrounding the Vredefort structure in South Africa is long and complex, involving several periods of contraction and extension. A general chronology of events covering a time span of 1000 Ma is established. The Vredefort deformation is identified as a separate structural event which is distinct from the earlier deformations. It is essential, therefore, that deformational structures related to the pre-Vredefort event should be identified and subtracted from the total spectrum of tectonism so that only those structures which can be related with certainty to the formation of the Vredefort structure are defined. This approach could influence interpretations of the origin of the Vredefort structure which attribute most structural and geological associations to the deposition of sediments onto a granitoid basement followed by a Vredefort deformational event. © 1990.