Abstract
The tectono-stratigraphic relationships, depositional environments, rock associations, and major- and trace-element compositions of the late Archean (2744-2696 Ma) bimodal basalt-rhyolite volcanic rocks of the Michipicoten (Wawa) greenstone belt, Ontario, are compatible with an origin along a convergent plate margin that varied laterally from an immature island arc built on oceanic crust to a more mature arc underlain by continental crust. This environment is similar to that of the Cenozoic Taupo-Kermadec-Tonga volcanic zone. The compositional similarity between the lower (2744 Ma) and upper (2696 Ma) volcanic sequences of the belt suggests that this island- and continental-arc configuration existed for at least 45 Ma. The Michipicoten belt may be a remnant of a larger, laterally heterogeneous volcanic terrane that also included the Abitibi greenstone belt.-from Authors
Original language | English |
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Pages (from-to) | 1120-1134 |
Number of pages | 15 |
Journal | Canadian Journal of Earth Sciences |
Volume | 24 |
Issue number | 6 |
DOIs | |
State | Published - 1987 |