Pan-African microplate accretion of the Arabian Shield
The late Proterozoic Arabian Shield is composed of at least five geologically distinct terranes (microplates) separated by four ophiolite-bearing suture zones. Three ensimatic island-arc terranes occur in the western shield, whereas the two terranes in the eastern shield have continental affinities. The western two sutures are island-arc-island-arc joins, whereas the eastern two sutures collectively form a major coilisional orogenic belt. Accretion of the five terranes to form an Arabian neocraton occurred from 715 to 630 Ma. After accretion, intracratonic deformation and magmatism related to collision continued and resulted in the formation of molasse, intermediate to silicic volcanic rocks, peralka-line to peraluminous granites (640-570 Ma), and a major left-lateral wrench fault system (∼630-550 Ma) which displaced the northern part of the Arabian neocraton ∼250 km to the northwest. These tectonic events represent the accretion of the Arabian portion of Gondwanaland during the Pan-African event.