Silurian-early Devonian mafic rocks of the Piscataquis volcanic belt in northern Maine

Abstract

The Silurian-Early Devonian eruptive rocks at selected sites in the Piscataquis volcanic belt in northern Maine are composed of mafic and felsic rocks with rare intermediate types. The Silurian-Early Devonian volcanic rocks were primarily erupted in a within-plate extensional environment that terminated with limited subduction. This extensional environment is inferred to be associated with the sinistral accretion of the Avalon Composite Terrane that produced an oblique pull-apart rift in adjacent Laurentia. -from Authors