Early Devonian bimodal volcanic rocks of Southwestern New Brunswick: petrography, stratigraphy, and depositional setting

Abstract

to subaenastal volcanic belt of the northeastern United States and New Brunswick consists of a bimodal sequence of marine of New Brutfurian and Early Devonian volcanic and assocUted sedimentary rocks. The Mascarene lithostratigraphic terrane depositional styletf probably the northern extension of this belt. This paper describes the volcanic stratigraphy, eruptive and Passamaquoddy Bay geography and tectonic setting of a 125 km2 area of the Mascarene terrane located along the coast of rhyolitic and basaltic flo^a mapped includes a - 3.5 km thick bimodal and subalkaline volcanic sequence of ""^ded GeorgeBathoUthandoverlain'fiyroclastic rocks and terrigeneous shale and sandstone. These rocks were intruded by the St. which aremappable at ascale of iformablyby the Late DevonianPerry Formation. The area is divided into 53 hthologic units Hawaiian, StromboIian,Piiniana39 • Rhyolitic rc>cks are volumetrically most irnportanL phreatomagmatic tuff cone, and peperitic *«*»