Dynamic topography of Central and Southern Africa

Abstract

Africa’s basin and swell topography is thought to be dynamically supported by mantle convection because it correlates closely with long wavelength free-air gravity anomalies, which can be regarded as a proxy for the convective pattern. Seismic tomographic studies reveal a region of slow seismic velocity beneath sub-equatorial Africa. This region broadly correlates with a zone of anomalously high elevation, known as the African Superswell, that stretches from the South Atlantic Ocean across Africa to Afar. More recently temporal parameters such as uplift rate have been considered in dynamic topography modeling. However, theoretical predictions of dynamic topography have not been carefully tested against observations.