الفهرس 
arabic summary
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Abstract
The Akarem Gabbro Intrusion is one of the Late-Precambrian younger mafic-ultramafic intrusions exposed in the south Eastern Desert of Egypt. It was emplaced along a fault related to the N60E block faults (Garson &Krs 1976). The AGI occurs as an elongated dike-like mass of composite nature. It is constituted of predominate gabbroic rocks or phase intruded by a peridotite phase; the enclosing diorite country rocks may (but not proven) represent an earlier cogenetic magmatic phase. The mutual contacts between the peridotites and the gabbros and the enclosing diorites dip usually inward. The contacts between the peridotite and gabbroic phases are steeper (40-50°) than that between the gabbroic rocks and the surrounding dioritic rocks (30-40°) implying a funnel-shaped intrusion. Lithologically, the peridotite phase comprises essentially lehrzolite, dunite, harzburgite, orthopyroxenite and websterite together with minor melanocratic gabbros. The gabbroic phase comprises essentially gabbronorite, norite, gabbro and hornblende gabbro together with minor websterite, melanocratic gabbro and troctolite. Whole rock compositions and mineral chemistry indicate that both the peridotitic and gabbroic phases were derived from the same parent magma and the composite nature of the AGI is the result of the mode of emplacement. So, models involving only simple fractional crystallisation by crystal settling do not adequately describe how the AGI was formed.