GraphicalabstractCondensed timetable of major geologic events in the East African Orogen. Opening of the Mozambique Ocean and formation of rift basins in Zambia, Malawi, Mozambique and SW Madagascar was accompanied by emplacement of anorthosite melt in extending crust. A first phase of ocean closure and accretion of terranes defines the East African Orogeny. The second orogen phase, Kuungan Orogeny, mainly affected the southern parts of east Africa and Madagascar. Both shortening events were followed by extension phases that were accompanied by emplacement of late- to post-tectonic granitoids. EGCD: Eastern Granulite–Cabo Delgado Nappe Complex; Madag: Madagascar; Ub–Us: Usagaran/Ubendian Belts; WG: Western Granulite Belt; IB (Z–M): Irumide Belt of Zambia and Malawi; IB (M): Irumide Belt of Mozambique.

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Digital Elevation Models (DEM) extracted from the Shuttle Radar Topography Mission (SRTM) data and high‐resolution aeromagnetic data are used to characterize the growth and propagation of faults associated with the early stages of continental extension in the Okavango Rift Zone (ORZ), northwest Botswana. Significant differences in the height of fault scarps and the throws across the faults in the basement indicate extended fault histories accompanied by sediment accumulation within the rift graben. Faults in the center of the rift either lack topographic expressions or are interpreted to have become inactive, or have large throws and small scarp heights indicating waning activity. Faults on the outer margins of the rift exhibit either (1) large throws or significant scarp heights and are considered older and active or (2) throws and scarp heights that are in closer agreement and are considered young and active. Fault linkages between major fault systems through a process of “fault piracy” have combined to establish an immature border fault for the ORZ. Thus, in addition to growing in length (by along‐axis linkage of segments), the rift is also growing in width (by transferring motion to younger faults along the outer margins while abandoning older faults in the middle). Finally, utilization of preexisting zones of weakness allowed the development of very long faults (>100 km) at a very early stage of continental rifting, explaining the apparent paradox between the fault length versus throw for this young rift. This study clearly demonstrates that the integration of the SRTM DEM and aeromagnetic data provides a 3‐D view of the faults and fault systems, providing new insight into fault growth and propagation during the nascent stages of continental rifting.

The Blue Nile Basin, situated in the Northwestern Ethiopian Plateau, contains $1400 m thick Mesozoic sedimentary section underlain by Neoproterozoic basement rocks and overlain by Early-Late Oligocene and Quaternary volcanic rocks. This study outlines the stratigraphic and structural evolution of the Blue Nile Basin based on field and remote sensing studies along the Gorge of the Nile. The Blue Nile Basin has evolved in three main phases: (1) Triassic-Cretaceous NE-SW-directed extension related to the Mesozoic rifting of Gondwana. The Blue Nile Basin was formed as a NW-trending rift, within which much of the Mesozoic clastic and marine sediments were deposited. This was followed by Late Miocene NW-SE-directed extension related to the Main Ethiopian Rift that formed NE-trending faults, affecting Lower volcanic rocks and the upper part of the Mesozoic section. The region was subsequently affected by Quaternary E-W and NNE-SSW-directed extensions related to oblique opening of the Main Ethiopian Rift and development of E-trending transverse faults, as well as NE-SW-directed extension in southern Afar (related to northeastward separation of the Arabian Plate from the African Plate) and E-W-directed extensions in western Afar (related to the stepping of the Red Sea axis into Afar). These Quaternary stress regimes resulted in the development of N-, ESE-and NW-trending extensional structures within the Blue Nile Basin.

The Oko Shear Zone is a late Precambrian, N- to NW-trending, post-accretionary deformational belt in the Red Sea Hills of the Sudan. It left-laterally offsets the c . 800–750 Ma old, NE-trending Nakasib suture by about 10 km. The Shear Zone evolved through three phases of deformations: (1) an early E-W-directed flattening deformation which produced N-trending upright folds; followed by (2) major NW-trending, left-lateral and, minor NE-trending, right-lateral strike-slip faulting; and (3) late E- and W-verging thrusts and buckles associated with a flower structure. The structural similarities between the Oko Shear Zone and other post-accretionary deformational belts in the Arabian-Nubian Shield suggest an evolutionary sequence for these belts: (1) suturing events were completed by c . 700 Ma ago 'and resulted in the formation of E- to NE-trending ophiolite-decorated sutures; (2) an E-W-directed flattening deformation was superimposed due to collision of the Arabian-Nubian Shield with the Nile craton in the west and the Ar Rayn micro-plate to the east at c. 670–610 Ma ago; this produced discrete zones of N-trending upright folds; (3) the flattening deformation culminated in the initiation of major NW-trending, left-lateral, and minor NE-trending, right-lateral strike-slip faults as conjugate sets at c. 640–560 Ma ago.