Gneissic granodiorite was recovered by drilling at the base of the Mazagan escarpment, 100 km west of the Casablanca, Morocco, at 4000 m water depth. Coarse, predeformative muscovite yielded dates of -515 Ma, fine-grained muscovite of -455 Ma, biotite -360 and 335 Ma, and feldspar -315 Ma. These dates are tentatively correlated with the microscopic results. We assume a minimum age of middle Cambrian for the granodiorite, an Ordovician deformation and mylonitization, and a Late Carboniferous overprint under upper greenschist facies conditions.
Supplement to: Kreuzer, H; Müller, P; Wissmann, Gerd; Reinecke, T (1984): Petrography and K-Ar dating of the Mazagan granodiorite, Deep Sea Drilling Project Leg 79, Holes 544A and 547B. In: Hinz, K; Winterer, EL; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Govt. Printing Office), 79, 543-549, doi:10.2973/dsdp.proc.79.118.1984
