Crossitic amphibole and its possible tectonic significance in the Richmond Area, southeastern Quebec

Abstract

Crossitic amphibole suggesting blueschist-type metamorphism has been found in the Richmond area, southeastern Quebec. Prehnite facies metamorphism to the northeast of Richmond and greenschist facies metamorphism to the south along with the blueschist-type metamorphism and geophysical data suggest that the Richmond area may represent a partially eroded Ordovician subduction zone.