S-type characteristics of the Hercynian granitoids of the Central Palaeozoic Massif, Morocco

Abstract

This petrographic and chemical study of the Hercynian granitoids of the Central Palaeozoic Massif of Morocco covers the Zaër, Ment, Oulmès, and Moulay Bouazza plutons. These plutons are formed of biotite or two-mica, quartz-rich granodiorites and monzogranites containing reddish-brown, inclusion-rich biotites as the only essential mafic mineral; zoned plagioclase; and perthitic K-feldspar. The modal contents of micas and K-feldspar are highly variable. The granitoids are generally medium to coarse grained, massive; however foliated varieties are also commonly found, particularly at the contact of the' plutons with sedimentary rocks.The strongly peraluminous character of the granitoids is shown by high normative corundum and high molar Al2O3/(CaO + Na2O + K2O) ratio, and is reflected by the occasional presence of aluminosilicates.The mineralogical and chemical characteristics of the granitoids are similar to those of the S-type granites, and were inherited from the crustal source of the granitic magmas which are thought to have been generated by partial equilibrium fusion of the sandy argillaceous sediments of the Massif. The heat source for the fusion might have been provided by intrusion of mantle-derived material.

Geochemical and Sr–Nd isotopic constraints on the petrogenesis and geodynamic significance of the Jebilet magmatism (Variscan Belt, Morocco)

“…1998). The leucogranites are typical S-type granites (0.707 < Sr i < 0.718; −10.7 < ε Nd < –1.5) derived from metasedimentary source rocks (Mahmood & Bennani, 1984; Mrini et al . 1992).…”

Evidence for surface uplift of the Atlas Mountains and the surrounding peripheral plateaux: Combining apatite fission-track results and geomorphic indicators in the Western Moroccan Meseta (coastal Variscan Paleozoic basement)

“…2). These granite bodies are biotite granodiorites to two micas monzogranites (Mahmood and Bennani, 1983). In the Rehamna region there is also the Rehamna Batholit formed by monzogranites and leucogranites.…”

Geochimie geochronologie (U-Pb) du pluton d Aouli et comparaisons geochimiques avec d autres granitoides hercyniens du Maroc par analyse discriminante

“…D'excellents résumés de la méthodologie sont disponibles dans Tatsuoka (1970), Klecka (1980) et Le Maître (1982. Shaw (1972) Mahmood,1980;Guiliani,1982Mahmood et Bennani, 1984Boushaba, 1984Mahmood et Bennani, 1984Richard, 1988Richard, 1988Richard, 1988Richard, 1988Vogel et Walker, 1975Gasquet (1992 (Fig.l), au sein d'une série métamorphique. Il est constitué de cinq groupes de roches: gabbros, diorites, granodiorites-tonalites, monzogranites et leucogranites (Gasquet, 1989).…”