Syn-orogenic high-temperature crustal melting: Geochronological and Nd–Sr–Pb isotope constraints from basement-derived granites (Central Damara Orogen, Namibia)

Role of crustal contribution in the early stage of the Damara Orogen, Namibia: New constraints from combined U–Pb and Lu–Hf isotopes from the Goas Magmatic Complex

“…The absence of superchondritic values excludes a relevant contribution from a depleted mantle source. These data are in good agreement with Paleo-to Mesoproterozoic Nd model ages for Damara granitoids provided by McDermott (1986), Jung et al (1998Jung et al ( , 2001, Jung (2005) and Ostendorf et al (2014), and suggest that no significant amount of juvenile crust was formed during this time in the region. In terms of magma genesis, Jung et al (2002) have compared geochemical data of Goas quartz-diorites with experimental data, and have suggested that the early magmatism was triggered in the lower crust by high P-T melting of a medium-K mafic protolith.…”

“…Nd model ages at 1.4 and 1.8 Ga were measured by in granites and granodiorites in the SCZ. In the same zone, granites and leucogranites with late Archean to early Proterozoic Nd model ages (2.0-2.5 Ga) have been reported by and Ostendorf et al (2014). Migmatitic rocks and residual xenoliths in Jung (2005) gave model ages between 1.6 and 1.8 Ga.…”

“…This developed through a series of tectonic, metamorphic and plutonic events in western-central Africa, and lead to the suturing of the Congo and Tanzanian Cratons in the Central African Craton, and to the orogenesis along the western margin of the Central and Southern African Cratons (Zhao et al, 2002;Dirks et al, 2003, and references therein;Begg et al, 2009, and references therein). In the Damara Orogen, Eburnean ages are widespread, both in the Congo and Kalahari cratonic domains, and are reported in Burger et al (1976), Jacob et al (1978), Tegtmeyer and Kröner (1985), Seth et al (1998), Steven and Armstrong (2002), Jacob et al (2000), Lobo-Guerrero Sanz (2005), Van Schijndel et al (2011) andOstendorf et al (2014). The cluster at around 1.1 Ga in Fig.…”

“…Data represent U-Pb crystallization, inherited and migmatization ages obtained using SHRIMP, ICP-MS, LA-ICP-MS, LA-SF-ICP-MS, SIMS, TIMS and CA-TIMS techniques. Ostendorf et al (2014) at ca. 2.2 Ga. εHf t measured on the 5 inherited cores is between −6.3 and −5.6, corresponding to a late Archean model age of ca.…”

Petrology of ferroan alkali-calcic granites: Synorogenic high-temperature melting of undepleted felsic lower crust (Damara orogen, Namibia)

“…Temperature and pressure estimates on the Bloedkoppie granite and other early-to syn-orogenic granites indicate that the lower crust was already hot at the time of the inferred onset of the first metamorphic peak (e.g. Ostendorf et al, 2014;Osterhus et al, 2014;Jung et al, 2015). Temperature-pressure estimates on high-grade metamorphic rocks from the Central Zone and temperature estimates on early syn-orogenic granites imply a geothermal gradient of ca.…”