الفهرس | Only 14 pages are availabe for public view |
Abstract Gabal Monqul area is located south of Ras Gharib city. It is bounded by latitudes 27° 48’ 30” to 27° 53’ 30” N and longitudes 33° 02’ 30” to 33° 06’ 30” E. Field investigations reveal that the rocks, which were mapped are older granitoids, Dokhan volcanics, Hammamat sediments and younger granitoids. The Dokhan volcanics constitute a thick sequence of stratified lava flows of basalt, andesite, imperial porphyry, dacite, rhyodacite and rhyolite together with subordinate sheets of ignimbrite. These lavas are interbanded with their pyroclastics including banded ash flow tuffs, lithic tuffs, crystal lapilli tuffs and agglomerates. These rocks are affected by brittle deformation which is represented by fracture, joints and faulting. The ground spectrometric survey shows that the south Monqul is clearly increased in the T.C, K, eU and eTh values which are related to zircon and monazite in addition to minerals as copper (chrysocolla and tenorite), barite, and pyrite as well as gold. Geochemically, the Dokhan volcanics are clearly of calc-alkaline affinity and fall mainly in continental basalts and volcanic arc setting. These volcanics show noticeable increase in Rb, Zr, Y, Nb and Th with increasing differentiation index. |