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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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A terrane map of North‐East Asia at 1:5 000 000 scale has been compiled. The map shows terranes of different types and ages accreted to the North‐Asian craton in the Mesozoic–Cenozoic, sub‐and superterranes, together with post‐amalgamation and post‐accretion assemblages. The great Kolyma‐Omolon superterrane adjoins the north‐east craton margin. It is composed of large angular terranes of continental affinity: craton fragments and fragments of the passive continental margin of Siberia, and island arc, oceanic and turbidite terranes that are unconformably overlain by shallow marine Middle‐Upper Jurassic deposits. The superterrane resulted from a long subduction of the Paleo‐Pacific oceanic crust beneath the Alazeya arc. Its south‐west boundary is defined by the Late Jurassic Uyandina‐Yasachnaya marginal volcanic arc which was brought about by subduction of the oceanic crust that separated the superterrane from Siberia. According to paleomagnetic evidence the width of the basin is estimated to be 1500–2000 km. Accretion of the superterrane to Siberia is dated to the late Late Jurassic‐Neocomian. The north‐east superterrane boundary is defined by the Lyakhov‐South Anyui suture which extends across southern Chukotka up to Alaska. Collision of the superterrane with the Chukotka shelf terrane is dated to the middle of the Cretaceous. The Okhotsk‐Chukotka belt, composed of Albian‐Late Cretaceous undeformed continental volcan‐ites, defines the Cretaceous margin of North Asia. Terranes eastward of the belt are mainly of oceanic affinity: island arc upon oceanic crust, accretion wedge and turbidite terranes, as well as cratonic terranes and fragments of magmatic arcs on the continental crust and metamorphic terranes of unclear origin and age. The time of their accretion is constrained by post‐accretionary volcanic belts that extend parallel to the Okhotsk‐Chukotka belt but are displaced to the east: the Maastrichtian‐Miocene Kamchatka‐Koryak belt and the Eocene‐Quaternary Central Kamchatka belt which mark active margins of the continent of corresponding ages.