Geochemistry and Geotectonic Setting of the Post-orogenic granites at Qala en Nahal-Um Sagata Area, Gedarif State, Sudan

Abstract

The survey area is located about 70 km southeast of Gedarif city, in Gedarif State east of Sudan, within two major lithological associations, representing two different crustal entities; Saharan Metacraton (SMC) in the west and the Arabian Nubian Shield (ANS) to the east. This study aims to investigate the post-orogenic granites at Qala En Nahal-Um Sagata. Geologically, both the petrographic characteristics and rock geochemistry investigation have been conducted in order to determine the tectonic environment and original protolith of these granites rocks. The area is made up of predominantly low-grade volcano-sedimentary rocks, ophiolite complex and belt of high-grade metasediments and gneiss into which voluminous granitic rocks have been emplaced. The post-orogenic granites of Ban-Balos are non foliated, high K calc-alkaline, I-type, post-dating the main collisional event emplacement at shallow levels intrusions.