Isotopic Dating and New England Stratigraphy

Owing to the relative ease with which fossiliferous units can be traced into the highly metamorphosed, highly deformed terrane of southern New England, northern Appalachian orogenic events are subject to much tighter biostratigraphic control than is common in comparable areas. In most instances, for Ordovician through Early Devonian time, the precision of this biostratigraphic dating exceeds that which can be attained by isotopic dating, even for intrusive bodies. For the most part, post-Early Devonian stratigraphic control is lacking, and isotopic methods are commonly the best means of dating younger rocks and events. In spite of the good stratigraphic control and...