Orogeny in 1890 to describe the process of mountain building as distinguished from epeirogeny. The formation of an orogen can be accomplished by the tectonic processes such as oceanic subduction (where a continent rides forcefully over an oceanic plate for accretionary orogeny) or continental subduction convergence of two or more continents for collisional orogeny). Orogeny usually produces long arcuate (from the Latin "", "to bend like a bow") structures, known as "orogenic belts". Generally, orogenic belts consist of long parallel strips of rock exhibiting similar characteristics along the length of the belt. Although orogenic belts are associated with subduction zones, subduction
Acadian orogeny the central to southern Appalachians, evidence for the Acadian orogeny is poor, and is found primarily in the plutonism of the Blue Ridge and metamorphism of the Cat Square terrane. The Acadian orogeny experienced at least three major phases of deformation, and in places, unconformities were recognized. These phases were called tectophases, and represented the sequence of collisions that occurred from the Avalonian terranes accreting to Laurentia. As a result of these tectophases, deltas developed on the adjacent parts of the stable craton, eastern margin of Laurentia. These deltas are described as foreland-basin, delta-complex clastic wedges, which are responsible for