Conductive incubation and the origin of dome-and-keel structure in Archean granite-greenstone terrains: A model based on the eastern Pilbara Craton, Western Australia

Abstract

The Archean East Pilbara Granite-Greenstone Terrane (EPGGT) of the Pilbara Craton in Western Australia preserves a prolonged record of voluminous mafic-dominated volcanism and felsic plutonism, commencing at circa 3515 Ma and ultimately resulting in the development of spectacular "dome-and-keel" structures. Early crustal growth was dominated by basaltic magmatism and the regional development of a 12-18 km thick greenstone sequence by circa 3335 Ma, overlying widespread 3470-3430 Ma tonalite-trondhjemite-granodiorite (TTG) suites emplaced into the middle crust. Stratigraphic and structural relationships imply that voluminous granitoid plutonism and crustal-scale dome-and-keel formation in the..