This paper describes the deformation and metamorphism recorded in the Zoovoorby staurolite schist, a sliver of pelitic supracrustal material in the 1.3-1.0Ga eastern Namaqua Province, South Africa. The supracrustal Biesjepoort Group, of which the schist is a part, has undergone at least four phases of deformation (DI-D,). DI and D2 are preserved in the pelitic schists; staurolite and garnet grew during D,, with staurolite growth persisting to the very earliest D, menulation. Andalusite, found in more Mg-rich schists, grew during D,, overprinting both S, schistosity and S, banding. S, has been rotated both with respect to SI (preserved as parallel orientated inclusion trails in garnet and staurolite) and with respect to its original orientation (preserved as open D2 crenulations in staurolite). Staurolite is dissolved against S, in zones of progressive shear. The pseudomorphing of staurolite and andalusite by midierite, and the preservation of relic grains of both minerals in a wide range of garnet-cordierite pelites throughout the eastern Namaqua Province infers that what is preserved fortuitously in the Zoovoorby locality is representative of the early metamorphic history of a much larger terrane. The high thermal gradients needed to attain estimated conditions of 540-550" C and 1.62.4 kbar require substantial heat input. Large amounts of foliated (syn-D,) granite amongst the supracrustal succession are inferred to be the result of delamination of a thickened crust at a destructive plate margin, generating an elevated thermal gradient during D1-D2 times.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.