Interaction of a Spreading Mantle Plume Head and the Ancient Lithosphere: Studying Mantle Xenoliths in Basalts and Lamprophyre Diatremes of Western Syria

Abstract

—Our study of mantle xenoliths in the Cretaceous lamprophyre diatremes and late Cenozoic plateau basalts of western Syria has shown that the ancient lower crust that existed in the Cretaceous and was composed of garnet granulites and eclogite-like rocks was replaced by mantle peridotites in the late Cenozoic. We conclude that the heads of the local (secondary) plumes of the present-day Afro-Arabian thermochemical mantle plume responsible for the regional basaltic magmatism reached the basement of the ancient upper sialic crust, where they spread, leading to a displacement of the mafic lower crust.