ABSTRACT
New U/Pb zircon and Rb/Sr geochronological data are used to constrain the ages of major tectonic events along the late Precambrian Nakasib suture (NS) and the Oko shear zone (OSZ) which are located in the center of the Red sea Hills of the Sudan and represent part of the 950–550 Ma old Arabian-Nubian Shield (ANS). These data suggest the following sequence: (1) Rifting of the 900–850 Ma Haya terrane at around 790 Ma ago. This culminated in the development of a proto-oceanic basin. (2) Deposition of passive margin sediments on the S flank of the basin between 790 and 780 Ma ago. (3) Development of a NW-dipping subduction zone to the N over which a pre-750 Ma old arc volcanics and sediments accumulated. (4) The closure of the basin between 780 and 740 Ma ago to form the NS. (5) The NS was left-laterally offset by the NNW-trending OSZ which developed sometimes between 700 and 560 Ma ago.
