Establishing if and when South Atlantic hotspots interacted with surface processes during rifting and continental
breakup is important for understanding the mechanisms that control the evolution of passive margins and their
adjacent continents. One approach is to reconstruct the volcanic history of hotspot trails located on the African
Superswell in order to find the locations of hotspots during rifting and breakup to determine if, for example, they
caused extreme fluxes of magma and post-rift uplift along the continental margin. However, because hotspot trails
located south of the classical Tristan-Gough are virtually un-sampled we don’t know how many hotspots might
have existed or for how long, and whether they originated from the core-mantle boundary or much shallower
depths. In 2006 we dredge sampled hotspot trails located on the African Superswell using the RV Polarstern, an
icebreaker capable of working in the poor weather conditions in the Southern Ocean. Combining new and existing
Ar/Ar isotopic ages shows that volcanism migrated synchronously along co-parallel hotspot trails consistent with
northeastern African plate motion relative to the leading edges of the African Superswell and an underlying stable
Superplume (large low-shear-velocity province) extending from the core-mantle boundary. Between roughly 132
and 100 million years ago only the Tristan-Gough hotspot trail developed where rifting and breakup facilitated
the rise of hotspot melts to the surface, while along rest of the leading edge hotspot volcanism was suppressed by
the African continent. Such a notion implies that the African passive continental margin was migrating relative to
the leading edge of the African Superplume for as long as 30 million years after continental rifting and breakup
had facilitated the 132 Ma Parana-Etendeka continental flood basalts and initiation of the Tristan-Gough hotspot
trail. This provides a mechanism for extended late stage interplay between deep mantle processes and the passive margin and adjacent continents that might explain extensive magmatism, lithospheric thinning and phases of postrift
uplift