Contribution à l’étude géologique et pétrographique des roches magmatique basique de la région Amrioune (El Milia-NE Algerie)

Abstract

This work is registered in the frame work of geological study, petrographic of a basic nature in the Amrioune region Petrographic and mineralogical of magmatic rocks dolerite of a basic nature in the Amrioune region. The dyke dolerite intrude the mauritanian flush median which are composed of flysch schisto sand stone and Calcareous schist, these latter are so metamorphosed in the contact of the dolerite intrusion The study of this is realised with a microscopic exam with the reflected light and the transmitted light, it shows that these dolorite basalts are composed essentially of primary minerals plagioclase and clinopyroxane and secondary ones like quartz, calcite, épidote, chlorite and hematite Prodects of alteration plagioclase and pyroxene As well as the intergranular dolerite texture.Those geologic and petrographic datas are moderate but they give a view that dolerite are placed in the end of Jurassic and corresponds to the phenomena marked in this period especially the phiolite magmatism in the flysch sayon .