الفهرس 
The pan-african belt of EgyptOnly 14 pages are availabe for public view
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Abstract
A detailed geological map for the rocks under study has been constructed. What has been known as the Atud Formation around Qift-Qusier road district here includes three distinct lithologic units (Map I): I- The Um-Esh Olistostromal Melange II- The Muweilih Conglomerate III-The Hamrnamat Molasse. Table 9.1. summarizes the main differences between the different studied rock units. I. The Urn Esh Olistostromal Melawe The Um Esh Olistostromal melange occupies the eastern part of the previous Atud belt, and is unconformably overlain by the studied Hammamat molasse sediments. The present olistostromal melange contains metaconglomerates and metagreywackes, with thin intercalations of metapyroclastics and schists. These contain native and exotic clasts of different sizes up to olistolith. The native clasts include intermediate and acidic metavolcanics and metapyroclastics. The exotic clasts include ophiolite components (metabasalt, schistose amphibolite and metamorphosed ultramafics), tosether with pebbles and cobbles of chert, quartzite, marble and granite. Tne rocks have undergone various degrees of regional metamorphism up to the greenschist facies. The volcaniclastic meta~revwackes, constituting the matrix of the present olistostromal melange, are petrochemically similar to the oceanic island arc sandstones which dominantly derived from calc-alkaline intermediate to acidic rocks deposited in forearc, interarc, back-arc basins and trenches. The native intermediate and acidic metavolcanic clasts follow the calcalkaline differentiation trend and originate in an island arc environment. The exotic clasts of metabasalts, schistose amphibolites and metamorphosed ultramafics are tholeiitic pertain ”normal” mid-ocean ridge basalt (N-type MORB). They also sirnilate back-arc basin ophiolites.