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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 ?
Alleghenian reactivation of the Acadian fold belt, Meguma zone, southwest Nova Scotia.
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.
It accreted to eastern North America during the mid-Devonian Neoacadian orogeny, with further juxtaposition during the Alleghenian (Waldron et al.
U-Th-Pb geochronology of the Massabesic Gneiss and the granite near Milford, south-central New Hampshire: New evidence for Avalonian basement and Taconic and Alleghenian disturbance in eastern New England.