Abstract
Models that have been proposed for evolution of the Archean crust can be considered as either fixist, involving processes acting in place such as rifting and diapirism, or mobilist, involving horizontal processes such as lithospheric plate movements, of which rifting and diapirism are adjuncts.
Consideration of regional geology of a portion of Superior Province suggests that supracrustal sequences can be traced across subprovince boundaries, but that the boundaries have been subsequently modified by considerable faulting both dip-slip and strike-slip. Within the Wabi-goon Subprovince lowermost supracrustal sequences are everywhere of thick tholeiitic mafic volcanics that show no evidence of being ensialic.
Granite diapirism accounts for much but not all deformation of supracrustal sequences. Crustal shortening independent of diapirism is indicated by the style of thrust faulting. Geochronology supports the concept that batholithic invasion was coeval with calc-alkaline volcanism, and paleomagnetism confirms that cratonization was complete by about 2.6 Ga ago.
Fixist models do not fully explain these observations, whereas a mobilist model,because of its broader nature, can accommodate them all.