Syn-collisional detrital zircon source evolution in the northern Moroccan Variscides

Abstract U–Pb dating and Hf isotopic analyses of detrital zircon grains from Cambrian-Devonian strata in the Moroccan Mesetas were undertaken order to constrain its Paleozoic paleogeographic evolution. In this work, we analyzed 12 Late Devonian-Late Carboniferous samples syn-collisional rocks Western Eastern Mesetas. All our present significant Ediacaran (ca. 620 Ma) Rhyacian 2.1 Ga) populations, suggesting that West African Craton remained main source sediments for northern Morocco at least until Carboniferous. Locally, a Stenian-Tonian 1.0 Ga) population is also present, probably fed intermittent distant areas located NE Africa (e.g. Sahara Metacraton). The collisional evolution started with approach an Avalonian promontory Gondwana continental margin (latest Devonian - earliest Carboniferous), after closure Rheic Ocean. This process entailed former subduction oceanic lithosphere underneath terrane formation magmatic arc upper plate. scenario, first (Tournaisian; Tiflet Debdou-Mekkam areas) are characterized by 370 Ma), presumably derived arc, increasing number Mesoproterozoic dates, putatively sourced crust terrane. After initial collision, only Visean close exotic Ben Slimane area) displayed minor component. Finally, Jerada area recorded important Middle 330 Ma) population, Variscan granitoids emplaced Meseta attesting crustal thickening subsequent thermal maturation area.