الفهرس 
GEOLOGIC SETTINGOnly 14 pages are availabe for public view
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Abstract
Wadi Khud’a area lies in the Southern half of Baraneis sheet (NF36 P) on scale 1:250,000, South Eastern Desert of Egypt. It is a part of the late Precambrian PanAfrican orogeny forming the Arabian Nubian Shield. The area studied comprises the basement rocks covering about 324 km2. It lies between Latitudes 23 37? 09? 23 46? 50? N, and Longitudes 35 16? 49? 35 28? 02? E. Based on field observations and relationships between the exposed basement rock units of Wadi Khud?a area the rock units are geochronologically arranged as follows starting with the oldest : Granite Gneisses and Migmatites (Hornblende gneiss, Biotite gneiss and Hornblendebiotite gneiss), Old granites (Quartz diorite, Tonalite and Granodiorite), Younger gabbro (Hornblende gabbro), Younger granites (Biotite granite, Muscovite granite and Leucocratic granite), Post granite dykes (Basalt, Andesite). The geochemical study of the present work is interested only by muscovite granite of Wadi Khud?a. The geochemical classification of the muscovite granites in concern demonstrates three types of granites; monzogranite, syenogranite and alkali granite.the studied muscovite granite is marked by highly slilicic, alumina saturated (peraluminous), highK calcalkaline and very low content of HFSE and iron titanium minerals. The REE pattern of Khud?a granite clearly separate three patterns characterizing the three granitic types monzogranite, syenogranite and alkali granite. Radiometric investigation of the granitic rocks in the area is characterized by low radioactive intensity and no alteration zones and consequently no uranium redistribution or radioactive anomalies. The granites in the area have high potassium content and consequently richer in thorium relative to uranium which is fixed in the magma. This categorization is very profitable and safe for other purposes like using the stream sediments and the ground water in the area as raw materials in ceramic industries and agriculture activities. heavy minerals distribution in Wadi sediments, reflects that the fewer size fractions wadi contain high averages of heavy mineral. Opaque minerals are the most dominant (ranging between 30.8% and 41.3% of the total heavies), brown clinopyroxene, green and brown hornblende, biotite, epidote and garnet minerals. Zircon, tourmaline and pale coloured and blue green amphibole minerals come in second order of concentration. The rarely encountered minerals are represented by other component of granitic and silicic metamorphic complexes (staurolite, monazite, kayanite, sillimanite and andalusite) as well as the mafic minerals of magmatic rocks (olivine and iddingsite).