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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.
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.
2006) and by a Paleozoic gneiss that is related either to the Taconic orogeny or the Alleghenian orogeny (Cardona et al.
1998; Waldron and van Staal, 2001 and references therein), whereas the Alleghenian orogeny was due to continent collision during final closure of the Rheic Ocean.
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.