The tectonometamorphic evolution of Nugrus Shear Zone (NSZ) in the south Eastern Desert of
Egypt was reevaluated through an integrated study including field-structural work and magnetofabric analysis
using Anisotropy of Magnetic Susceptibility (AMS) technique, complemented by detailed microstructural
investigation. Several lines of evidence indicate that the Neoproterozoic juvenile crust within this high strain
zone suffered an impressive tectonic event of left-lateral transpressional regime, transposed the majority of
the earlier formed structures into a NNW to NW-directed wrench corridor depicts the northwestern extension
of the Najd Shear System (NSS) along the Eastern Desert of Egypt. The core of the southern Hafafit
dome underwent a high metamorphic event (M1) developed during the end of the main collisional orogeny
in the Arabian-Nubian Shield (ANS). The subsequent M2 metamorphic event was retrogressive and depicts
the tectonic evolution and exhumation of the Nugrus-Hafafit area including the Hafafit gneissic domes,
during the origination of the left-lateral transpressive wrench corridor of the NSS. The early tectonic fabric
within the NSZ and associated highly deformed rocks was successfully detected by the integration of AMStechnique
and microstructural observations. Such fabric grain was checked through a field-structural work.
The outcomes of the present contribution advocate a complex tectonic evolution with successive and overlapped
deformation events for the NSZ. |
