TITLE:
Geochemical Characteristics and Chemical Electron Microprobe U-Pb-Th Dating of Pitchblende Mineralization from Gabal Gattar Younger Granite, North Eastern Desert, Egypt
AUTHORS:
Hassan A. A. Shahin
KEYWORDS:
Pitchblende Mineralization; Gabal Gattar Granite; Chemical U-Pb-Th Dating
JOURNAL NAME:
Open Journal of Geology,
Vol.4 No.1,
January
23,
2014
ABSTRACT: Pitchblende
mineralization was studied in the
younger granite samples collected from Gabal Gattar, north Eastern Desert, Egypt using electron scanning
microscope (ESM) and electron probe microanalyses (EPMA). This study revealed
that this pitchblende contains significant Zr content reaching up to (66.80% ZrO2), which suggests
that volcanic rocks were probably the source of such a deposit. High level
emplaced high-K
Calc-alkaline plutons as Qattar granite may have been associated with their
volcanic equivalent emplaced in the surrounding area or now eroded. Lead
content of the pitchblende mineralization is high and with moderate volcanics
(up to 7.71% PbO). In contrast, it is low in ThO2, Y2O3 and REE2O3. High Zr and Pb content associated with pitchblende mineralization from Gattar granite indicates that
the source of this
mineralization derived from volcanic magma not from granitic magma. According to the calculation of U-Pb chemical ages using U, Th and Pb content measured with an
electron microprobe for this pitchblende yielded ages within 543 - 657 Ma indicating a Pan-African age for this
mineralization. This is
the first time that a Pan-African age (543 to 657 Ma) is recorded for a U-mineralization in Gabal Gattar younger granite in the north Eastern Desert, Egypt.