Geochemical constraints from the Hafafit Metamorphic Complex (HMC): Evidence of Neoproterozoic back-arc basin development in the central Eastern Desert of Egypt

The northern dome of Wadi Hafafit culmination, Eastern Desert, Egypt: Structural setting in tectonic framework of a scissor-like wrench corridor

“…The inner unit comprises, from the core to rims: (1) a package of highly deformed ortho-and para-gneisses with intercalated bands of amphibolites; collectively known as core gneisses, and (2) a thick sequence of well-banded amphibolite and metasediment surrounding the core gneisses (Abd El-Naby and Frisch, 2006;Figs. 2 and 3).…”

“…The gneisses are invaded by numerous pegmatitic dykes and veinlets, which in some places contain garnets. The amphibolite bands surrounding the core gneisses are also strongly foliated and display alternating bands of metamorphic biotite-and hornblende-gneisses of amphibolitie facies (Rashwan, 1991;El Ramly et al, 1993;Abd El-Naby and Frisch, 2006). The banded amphibolites are overlain, to the east, by a package of a triangular zone of intensively folded biotite-and hornblend-rich metasediments, and by Hafafit psammitic gneisses to the south (Figs.…”

The Sha’it–Nugrus shear zone separating Central and South Eastern Deserts, Egypt: A post-arc collision low-angle normal ductile shear zone

“…Asran and Kabesh (2003) estimated the metamorphic conditions as 720-740°C for Migif-Hafafit amphibolites and 800-820°C for associated migmatites, both under pressures of 6-7 kbars. Abd El-Naby and Frisch (2006) concluded that the pressure conditions were 6-8 kbars.…”

“…Interestingly, frictional effects along the SNSZ have been implicated as a heat source sufficient to cause melting of shear zone schists producing leucogranite melts (Abdalla and Mohamed, 1999;Abd El-Naby and Frisch, 2006), and the leucogranites indeed have similar age to SNSZ shearing activity (Moghazi et al, 2004;Abd El-Naby and Frisch, 2006). However, it seems more likely that the abundance of magma and hydrothermal fluids along the SNSZ acted to reduce friction by raising fluid pressures along the shear zone.…”

Sr–Nd isotopes and geochemistry of granite-gneiss complexes from the Meatiq and Hafafit domes, Eastern Desert, Egypt: No evidence for pre-Neoproterozoic crust

“…Meatiq map from Loizenbauer et al (2001) andKhudeir et al (2008); Hafafit map from AbdEl-Naby and Frisch (2006) andFowler and El Kalioubi (2002).…”