Extreme uplift associated with the formation of the 2.02 Ga Vredefort dome has exposed a substantial cross section through the crystalline early Archean basement complex rocks of the Kaapvaal craton. The rocks comprise polydeformed high-grade tonalite–trondhjemite–granodiorite (TTG) gneisses, migmatites and late-tectonic intrusive granitoids that straddle the upper amphibolite-to granulite–faci...

Abstract Systematic changes in whole-rock chemistry, mineralogy, mineral textures, and chemistry are seen along a ca. 95-km traverse of late Archean granitoid orthogneisses the Shevaroy Block, Eastern Dharwar Craton, southern India. The passes from amphibolite-grade gneisses north to granulite-grade rocks (charnockite) south. Changes include depletion Rb, Cs, Th, U granulite grade as relative a...

Shear zones in the boundary between Eastern Ghats Province (EGP) and cratons of Singhbhum north Bastar west provide an excellent opportunity to study tectonics shear zone development its timing relation evolutionary history granulite suites. Detailed structural, microfabric quartz C-axis patterns revealed a high temperature zone, at western EGP Craton (BC) around Paikmal. Petrological studies t...

In the Geologists and Miller Ranges of the central Transantarctic Mountains, mafic and ultramalic tectonic blocks occur in an Early Cambrian amphiboliteto granulite-facies lower crustal transpressional shear zone. Mafic blocks consist of garnet + clinopyroxene symplectite + hornblende + plagioclase + quartz + ilmenite f orthopyroxene f biotite;mineral compositions in these blocks generally refl...

Garnet-whole rock and garnet-mineral isochrons were determined on granulite facies gneisses and amphibolites from the Archean Pikwitonei Granulite Domain of the Superior Province, and the Proterozoic Central Gneiss Belt and Adirondack Highlands of the Grenville orogen. The Sm-Nd ages obtained from Archean garnets 0.1-0.5 cm in length are 30-110 Ma younger than the U-Pb ages obtained on the same...

Marie and intermediate granulite xenoliths, collected from Cenozoic alkali basalts, provide samples of the lower crust in western Saudi Arabia. The xenoliths are metaigneous two-pyroxene and garnet granulites. Mineral and whole rock compositions are inconsistent with origin from Red Sea rift-reIated basalts, and are compatible with origin from island arc calc-alkatine and low-potassium tholeiit...