Lower Carboniferous volcano-sedimentary sequences from eastern Morocco: dating, composition and structural consequences

Early Carboniferous sequences in eastern Moroccan Meseta, are dated herein from Late Visean (V3b(gamma)) to Early Namurian (= Serpukhovian). The serie s, essentially constituted by shales and limestones, are interrupted by two volcanic events, respectively in V3b(gamma)-Early V3c and in Serpukhovian El. The latter are coeval with two major tectonic phases, first in V3b(gamm a) with horst and graben structuration, created by important faults N70, an d opening of the Beni-Snassene, Jerada and Mekam basins. A second major, ph ase at the V3c-Serpukhovian boundary, permits the opening of the Debdou-Taz ekka basin with faults N30. ((C) Academie des sciences/Elsevier, Paris.).