الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 172 |  |  |
| | | from | 172 | | |
Abstract
There are fifteen rock samples representing the main lithologies of the study area of granites and twenty-three samples collected from stream sediments in Wadi Lethi area north Sharm El-Sheikh area, Sinai.
The identified non-opaque heavy minerals of the collected fine fraction stream sediment samples are zircon, pyroxene, titanite, epidote, allanite, hornblende, garnet, riebeckite, biotite, chlorite, apatite and, xenotime. The most abundant mineral in the studied samples is riebeckite.
X-ray diffraction analyses of the heavy mineral very fine fraction stream sediment samples show that the identified minerals assemblages of one fraction are chlorite, biotite, titanite, apatite, garnet, columbite, riebeckite, chevkinite, monazite and tremolite, some of these minerals are easily detected by XRD as columbite, chevkinite, monazite, and tremolite.
Petrographically, the exposed country rocks revealed that there are four main types of granites which are monzogranite, syenogranite, alkali feldspar granite, and riebeckite granite.
Geochemical analysis of the studied bedrocks are consistent with petrographic investigations, the Monzo-syenogranites are generally magnesian, while alkali feldspar granites and riebeckite granites are ferroan.
The highest ∑REE reach of 497.4 ppm was found in riebeckite granite samples, while the lowest ∑REE reach of 153.7 ppm was found in monzogranite samples.
Abstract
Monzogranite and syenogranite’s minor Eu anomalies and less fractionated REE patterns are governed by amphiboles with minor plagioclase crystallization. This feature illustrates the divergent impacts of minerals on Eu differentiation, including feldspars (which develop a negative Eu anomaly) and hornblende and alkali pyroxenes (which develop a positive anomaly).
The geochemical analysis of the stream sediments of the study area showed that the REE trends of these minerals pointed to the same source or belonging to similar bedrocks, as well as an enrichment of light rare earth elements (LREEs) and a depletion of heavy rare earth elements (HREEs), along with the typical negative Eu anomaly that is characteristic of granitic magma.
The concentration of REEs in the stream sediments is 11 times that of REEs in bedrock, showing the economic abundance that we can exploit.