Also found in: Encyclopedia.
Related to Alleghenian: Appalachian Orogen


a.1.(Biogeography) Pertaining to or designating the humid division of the Transition zone extending across the northern United States from New England to eastern Dakota, and including also most of Pennsylvania and the mountainous region as far south as northern Georgia.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
40Ar/39Ar ages from the Narragansett Basin and southern Rhode Island basement terrane: their bearing on the extent and timing of Alleghenian tectonothermal events in New England.
Precambrian and Paleozoic collisions are recorded by a granulitic gneiss of Grenvillian age (Cordani et al., 2005, Cardona et al., 2006) and by a Paleozoic gneiss that is related either to the Taconic orogeny or the Alleghenian orogeny (Cardona et al., 2006; Zuluaga et al., 2009).
250 Ma) Paleozoic accretionary orogen, punctuated by accretion of small oceanic terranes and four major oblique collisional events: Taconic, Salinic, Acadian and Alleghenian. The first three orogenic events are mainly the result of the successive arrival of four microcontinents (Dashwoods, Ganderia, Avalonia and Meguma) at the Laurentian margin (Fig.
During the Pennsylvanian Period (320-286 Ma), the collision of North America and Africa resulted in the Alleghenian Orogeny and final assemblage of Pangaea.
The terrane is polydeformed by Acadian and Alleghenian tectonic pulses, presenting the full gamut of geologic mapping problems that must be addressed by GIS software.
Alleghenian reactivation of the Acadian fold belt, Meguma zone, southwest Nova Scotia.
It accreted to eastern North America during the mid-Devonian Neoacadian orogeny, with further juxtaposition during the Alleghenian (Waldron et al.