Discussion: The Terreneuvian MacCodrum Brook section, Mira terrane, Cape Breton Island, Nova Scotia, Canada: age constraints from ash layers, organic-walled microfossils, and trace fossils

Abstract

Exhaustive similarities in terminal Ediacaran–Ordovician cover sequences between tectonic inliers in the Appalachian–Caledonian (A–C) orogen define the Avalonian terrane from coastal northeast North America through southern Britain to Belgium. However, Barr et al. effectively block inclusion of the Mira belt (Mb) in Avalonia by masking a long-documented trans-Avalonian succession under locally defined lithostratigraphic names that prove to be confusing homonyms of themselves. Earlier revisions of Mira belt stratigraphy allow assignment of the Mira belt to a precise location in the Avalonian strike-slip regime—on the marginal–inner platform transition just as the northern Antigonish Highlands and southeast Burin Peninsula. The Mira belt is a tectonic inlier not a “terrane” in the A–C orogen.