Timing of the Granites magmatic activities, Wadi Abu Abid, North Eastern Desert, Egypt.

Granitic rocks represent a large portion of the Arabian-Nubian Shield (ANS) exposures in the North Eastern Desert (NED). The timing of the magmatic events plays a major role in illustrating the ANS development. In order to evaluate the ANS, it is important to understand their geochronological order. Therefore, we studied calc-alkaline and alkaline granitic samples from Wadi Abu Abid, Gabal Um Anab area, North Eastern Desert, Egypt, to chronologically evaluate the ANS magmatic process in the studied region. The results show ages of the syn-collisional compressional magmatic event for all the analyzed samples. The resulting ages extended from 755 ± 16 Ma to 667 ± 15 Ma, which represents some conflicts with the traditional classification of the granitoids as being either Older syn-collisional calc-alkaline granitoids or Younger post-collisional alkaline granitic rocks. Xenocrysts with pre-ANS ages noted in five zircon grains in two samples, given ages of 2006 ± 85 Ma, 1887 ± 84 Ma, 1616 ± 73 Ma, 1228 ± 73 Ma, and 1227 ± 70 Ma, which suggest a local rework of an older magmatic source.