We present a new analysis of the lithospheric architecture of Africa, and its evolution from ca. 3.6 Ga to the present. Upperlithosphere domains, generated or reworked in different time periods, have been delineated by integrating regional tectonics and geochronology with geophysical data (magnetic, gravity, and seismic). The origins and evolution of lower-lithosphere domains are interpreted from a high-resolution global shear-wave tomographic model, using thermal/compositional modeling and xenolith/ xenocryst data from volcanic rocks. These data are integrated to map the distribution of Begg et al. 24 Geosphere, February 2009 only the latest stage in this process. The less depleted SCLM that underlies some accretionary belts may have been generated in Archean time, and repeatedly refertilized by the passage of magmas during younger tectonic events. Our analysis indicates that originally Archean SCLM is far more extensive beneath Africa than previously recognized, and implies that post-Archean SCLM rarely survives the collision/accretion process. Where continental crust and SCLM have remained connected, there is a strong linkage between the tectonic evolution of the crust and the composition and modifi cation of its underlying SCLM.

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