Petrography and petrochemistry of Wadi Kareim iron-bearing formation, Eastern Desert, Egypt

The petrography of the Precambrian iron-bearing formation at Wadi Kareim proved that the formation consists of the following regionally metamorphosed rock types of the greenschist fades; 1. Graywackes (mainly volcanic grading to volcanic breccias, normal greywackes are less common). 2. Schists (chlo...

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Bibliographic Details
Main Authors: Niazy E. A.
El Bakry A.
Kamel O. A.
Format: Article
Published: University of Szeged, Department of Mineralogy, Geochemistry and Petrology Szeged 1984
Series:Acta mineralogica-petrographica 26 No. 2
Kulcsszavak:Kőzettan, Ásványtan, Földtan
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Online Access:http://acta.bibl.u-szeged.hu/24718
Description
Summary:The petrography of the Precambrian iron-bearing formation at Wadi Kareim proved that the formation consists of the following regionally metamorphosed rock types of the greenschist fades; 1. Graywackes (mainly volcanic grading to volcanic breccias, normal greywackes are less common). 2. Schists (chlorite, chlorite-calciie, and actinolite-epidote) 3. Volcanics (keratophyres, quartz-keratophyres, spiliies. spilitic diabase and diabase). 4. Pyroclastics (lithoclastic and crystal tuffs, lapilli tulTs — mainly spilitic in composition). The petrographic study iscorporatcd with the results of eight new chemical analyses, representing the different rock types. The analysis of the basic metavolcanic is similar to the average world spilite, and that of the acid metavolcanic is comparable to the aphanitic keratophyre (Schirmecktype) of the preorogenic Hercynian volcanics of Western Europe. The recently suggested Al/3—K versus Al/3 -Na and Si/3—(Na + K. 2Ca/3) versus K <Na + + Ca) diagrams, the FMA and Na—K.—Ca diagrams are adopted for the petrochemical presentation of the chemical data. It is suggested that most rock types either have a composition comparable lo basalts or spilitic mineral assemblages. This mostly reflects the primary link of the spilitic rock with other volcanic and pyroclastic rocks, particularly keratophyres. The only exception, is the chlorite schist which has a composition similar to shales.
Physical Description:187-205
ISSN:0365-8066