GEOCHEMICAL CHARACTERISTICS OF SOME PERALUMINOUS YOUNGER GRANITE MASSES, EASTERN DESERT, EGYPT

Sixteen representative samples of younger granites from Gabal El Mueilha, Gabal Harhagite and
Gabal Qash Amir in the central and south Eastern Desert of Egypt were analyzed for major, trace and rare
earth elements. Petrographical and geochemical studies revealed that, Gabal Harhagite is monzogranite,
while Gabal El Mueilha and Gabal Qash Amir are syeno- to alkali feldspar granites. They are classified as
I-type peraluminous granite (A/CNK=1.46-1.67), P-poor (P2O5 < 0.07 wt %) and Na2O-rich (≤ 7.08 wt%)
exhibiting differences in their REE contents. Gabal Qash Amir and Gabal El Mueilha are within- plate
granite whereas Gabal Harhagite is volcanic arc granite.
Peraluminous granite are good source for the uranium, rare metals (Nb-Ta, Be, W) and rare earths
(La,Lu, Nd, Dy ,Y) mineralizations are examined for Gabal El Mueilha, Gabal Harhagite and Gabal Qash
Amir younger granites. These granites show rare metal contents (Nb = 81, Yb = 20, U = 14, Ta = 25 ppm)
and in some rare earth elements (La = 12, Lu = 3, Y = 102, Nd = 17, Dy = 12 ppm). Chondrite-normalized
REE diagram shows that Gabal El Mueilha granite samples display strong HREE enrichment relative to
LREE which show flat pattern with moderate to strong negative Eu anomalies. On the otherhand Gabal
Harhagite and Gabal Qash Amir granite show high enrichment in LREE compared with HREE which
desplay slightly falling slope with strong to low negative Eu anomalies. Field radiometric measurements
revealed that the radioactivity level up to 34 ppm (eU). at Gabal El Mueilha granite , at Gabal Harhagite
granite reach up to 9.5 ppm (eU), while at Gabal Qash Amir granite reach up to 47 ppm (eU).This type of
granites assumed to be a specific type for tin and tungestin mineralizations.