Alleghanian orogeny

Alleghanian orogeny A phase of mountain building, that began in the Early Carboniferous and was completed by the end of the Permian, caused by the collision between N. America and Africa. It formed part of the general WSW to ENE Hercynian belt. The orogeny affected the Lower Palaeozoic basement and Lower Permian strata along the western margin of the southern and central parts of the Appalachian Mountains extending from what is now Pennsylvania to Alabama, with effects as far north as New Brunswick and Newfoundland. See APPALACHIAN OROGENIC BELT.