الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The basement rocks covering the area between Wadi Um-Maghra to Wadi Tweiba rep resent
one of the main metamorphic belts in Sinai and refer as ”Taba belt”. The Taba belt comprjses both
metamorphic and igneous rocks of Pan-African age (not more than 800 Ma ago) . where the
metamorphites represent about 77% of the total Precambrian exposu re. The metamorphic rocks
comprise schists. Metagabbro-diorite Complex which are related to the initial tectonic stage (backarc
association); migmatites, orthogneisses and associated schistose dykes which are related to the
syntectonic association. On the megascale. uprooting of the different rocks unitS due to ascending of
the Younger Granites with conjugate normal faults in between are observed.
A. Initial tectonic stage (back-arc association)
1. Schists
The schists occur in the northern part of the study area, where they rep resent the oldest rock
unit. {t is exposed at Wadis Tweiba. Khileifiya and el-Morakh. The preserved bedding strucrure and
tbe chemical criteria of the schists suggest their derivitation from a sedimentary source initially
dominated by psammitic to semipelitic (gr aywackes and pelitic graywackes) in composition. They
were depos ited in a tectonic setting intermediate between island arc and active continental margin
regime. At Wadi Tweiba. the schists are fine grained biotite-, garnet-bi otite~, staurolite-bioti te-, and
andalus ite biotite schist varities. At Wadi Khil eifiya. the schists are represented by biotite- and
garnet-biotite types, underwent retrograde overprint leading to chloritization of biotite and
sericitization of plagioclase . At Wadi el-Morakh , medium-grained biotite- and garnet-bi otite schist
varities are exposed. The predominant part of the schist belt belongs to the garnet zone. A smal!
area south tO Wadi ei-Morakh belongs to the biotite zone seperated from the garnet zone by the
WNW-ESE trending garnet isograde. Staurolite and andalusite bearing schists are confined to a local
area west to Wadi Tweiba, where the staurolite schists occur as bands in the biOtite and/or garnet
schists.