Plio-Quaternary Volcanism in Northeastern Morocco: Petrography and Geochemistry of Outcrops with High Geothermal Potential

Abstract

Cenozoic volcanic activity in Morocco started in the Miocene and proceeded, after a short break, during Pliocene and Quaternary. Calc-alkaline magmatic activity occurred first and was accompanied by the eruption of transitional lavas, followed by Plio-Quaternary alkali basaltic activity, which was emplaced within Neogene sedimentary basins of the Rif belt and its foreland. From calc-alkaline to alkaline magmatism, passing through a transitional term, volcanic activities in Morocco formed magnificent outcrops, very di-versified in their affinities, their mineral compositions and their geochemistry. The petrographic study and geochemistry of Plio-quaternary volcanic rocks in the areas with high geothermal potential in northeast of Morocco show a dominance of Na-rich basaltic rocks (basanites, basalts, tephrites and basaltic trachy-andesites), followed by trachy-andesites. Most of the samples exhibit an enrichment of large-ion lithophile elements (LILEs) over high-field-strength elements (HFSEs). These results were used to test the global model of Circum-Mediterranean Anorogenic Cenozoic Igneous Province (CiMACI) and the regional model of [1].