Late Palaeozoic to Neogene geodynamic evolution of the northeastern Oman margin

When the highlands of Arabia were still covered with an ice shield in the l atest Carboniferous/Early Permian period, separation of Gondwana started. T his led to the creation of the Batain basin (part of the early Indian Ocean ), off the northeastern margin of Oman. The rifting reactivated an Infra-Ca mbrian rift shoulder along the northeastern Oman margin and detritus from t his high was shed into the interior Oman basin. Whereas carbonate platform deposits became widespread along the margin of the Neo-Tethys (northern rim of Oman), drifting and oceanization of the Batain basin started only in La te Jurassic/Early Cretaceous time. Extensional tectonics was followed in th e Late Cretaceous by contraction caused by the northward drift of Greater I ndia and Afro-Arabia. This resulted in the collision of Afro-Arabia with an intra-oceanic trench and obduction of the Semail ophiolite and the Hawasin a nappes south to southwestward onto the northern Oman margin similar to 80 m.y. ago. During the middle Cretaceous, the oceanic lithosphere (including the future eastern ophiolites of Oman) drifted northwards as part of the I ndian plate. At the Cretaceous-Palaeogene transition (similar to 65 Ma), ob lique convergence between Greater India and Afro-Arabia caused fragments of the early Indian Ocean to be thrust onto the Batain basin. Subsequently, t he Lower Permian to uppermost Maastrichtian sediments and volcanic rocks of the Batain basin, along with fragments of Indian Ocean floor (eastern ophi olites), were obducted northwestward onto the northeastern margin of Oman. Palaeogene neo-autochtonous sedimentary rocks subsequently covered the napp e pile. Tertiary extensional tectonics related to Red Sea rifting in the La te Eocene was followed by Miocene shortening, associated with the collision of Arabia and Eurasia and the formation of the Oman Mountains.