الفهرس 
INTRODUCTION
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Abstract
The post-collisional Mueilha and Homrit Akarem intrusions were emplaced
into metamorphic country rocks with sharp intrusive contacts. They represent a
magmatic cupolas above highly fractionated A-type granites. The early phases of the
two intrusions reached subvolcanic conditions and emplaced a along the apex of the
magmatic cupola. Subsequently, the granitic magmas crystallized downwards forming
a differentiation series of hypabyssal granites. The main emplacement mechanism and
evolutionary sequence of the two granitic plutons was magmatic, although the effects
of hydrothermal fluids and extensive replacement by secondary minerals are observed
in the marginal zones at the apex of the two intrusion. The rock types of the MGP and
HAGP are nearly similar in their essential mineral compositions. They consist
essentially of K-feldspars, quartz and albite with less amounts of plagioclase and
mafic minerals. They contain wide variations of accessory minerals such as biotite,
muscovite, zircon, garnet, Nb-Ta oxides, fluorite, Fe-Ti oxides, apatite, sphene, topaz,
beryl, cassiterite and allanite. Nb-Ta oxides are the most important accessory minerals
in the MGP and HAGP. They include primary phases such as columbite and tantalite,
and secondary phases such as fluorcalciomicrolite and wodginite. Mineral chemistry
of biotite and garnet indicated their primary magmatic nature that crystallized from
peraluminous magma with A-type characters