Seismotectonic Models for South Africa: Synthesis of Geoscientific Information, Problems, and the Way Forward

Abstract

should be reviewed; surface and subsurface investigations of the orientation, geometry, sense of displacement, and length of ruptures should be conducted; and the possibility of multiple ruptures ought to be assessed. Seismotectonic models have not yet been developed for South Africa. The delineation of seismotectonic zones of Africa as part of the Global Seismic Hazard Assessment Program (GSHAP) in 1999 was based on an analysis of the main tectonic structures and a correlation with present-day seismicity. Because of the large scale of the GSHAP project, only regional structures were accounted for in the preparation of the source zones. Our study was initiated to remedy this knowledge gap. We have completed four steps, which are described in this paper. Compilation of a catalog of earthquake activity that has