Pyroxenite xenoliths and clinopyroxene megacrysts from the Cenozoic Jbel Saghro Volcanic Field (Anti-Atlas, Morocco): Petrography, mineral chemistry and equilibration conditions

A suite of mafic pyroxenite xenoliths and clinopyroxene megacrysts was brought to the surface by Cenozoic nephelinites Jbel Saghro Volcanic Field (Anti-Atlas, Morocco). The large population samples subdivided into five groups: (i) clinopyroxenites sensu stricto; (ii) olivine clinopyroxenites; (iii) mica-bearing (iv) kaersutite-bearing (v) megacrysts. These display a cumulate texture (adcumulate, heteradcumulate with poikilitic including olivine). clinopyroxenes have composition augite show an appreciable variation MgO (7.02–14.80 wt.%), TiO2 (0.58–5.76 wt.%) Al2O3 (2.81–12.38 contents in grains. are characterized convex upward chondrite-normalized REE patterns, they very similar trace element compositions low incompatible elements such as Rb (0−0.9 ppm), Ba (0.1–8.3 Th (0.1−0.3 U (0.01−0.04 ppm) Nb (1.3–3.2 ppm). calculated melts equilibrium from those exposed Saghro. Crystallization temperatures range 950 °C 1150 °C. Clinopyroxene barometry yielded pressure crystallization ranging 0.4 0.8 GPa for 0.3 0.7 This is agreement being crystallized their parental at lower upper crust.