Early Tectonic Evolution Of Oman Revisited: Implications for the evolution of North Eastern Gondwana and for the oldest hydrocarbon systems in Arabia

Abstract

Summary The Precambrian tectonic setting is important to understand the oldest petroleum systems of Oman, including the distribution of our main source rocks in the Huqf Supergroup, the reservoirs of the Nafun, Ara, Nimr and Haima plays, the basin subsidence history and diagenesis, and the early deformation history and trap creation. Recent multidisciplinary studies, including sedimentology, heavy minerals and detrital zircon geochronology, support that Oman formed at the western margin of the Indian Shield (Eastern Gondwana) during the Neoproterozoic (Tonian), and that it only collided with the Arabian-Nubian Shield (Western Gondwana) in the Early Cambrian (~525 Ma ago). This resulted in the formation of the Western Deformation Front, which marks the final suture between East and West Gondwana. Oman stayed as part of Arabia after Permian-Jurassic Gondwana break-up. These tectonic changes are tracked by depositional evolution, tectonic/magmatic events as seen by detrital zircon geochronology, and sediment distribution patterns. Our results entail a significant update to our present tectonic evolution and plate reconstruction models of eastern Arabia, and to our understanding of the early petroleum systems of Oman.