Late Carboniferous to Recent, Geodynamic Evolution of the West Gondwanian, Cratonic, Tethyan Margins

The development of the Late Carboniferous-Liassic, Late Jurassic—Early Cretaceous, and Late Eocene—Early Miocene western Gondwanian rift systems and related magmatic provinces is related to the reactivation of preexisting Pan—African zones of lithospheric weakness. It resulted in the breakup of Pangea and Gondwana, and the opening of the Indian Ocean, western Tethys, and the South Atlantic Ocean. Changes in the intraplate stress regimes of Africa—Arabia and South America are indicated by alternating phases of crustal extension, sag-basin development and lithospheric compression. The compressive events can be correlated with changes in the rate and direction of the opening of the Central, South, and North Atlantic oceans. However, the repetition of rifting episodes, particularly within wide areas of Niger and Sudan, the persistence of some rift-independent magmatic provinces (e.g., Nigeria and Nubia) and geophysical data suggest the presence of large-scale, mantle upwelling below equatorial Africa, which could explain the specific geodynamic history of the African Plate.