Some escarpments are formed by tectonic activity (ie, deformational movements of the Earth's crust or volcanism), particularly uplift along fault lines, and are distinguished as fault scarps. An excellent example is in the Aspy Valley of northern Cape Breton Island, NS. The angle of the fault scarp is controlled by the inclination of the fault plane and is often more gentle than that of the classic escarpment formed by strata of differing resistance. The latter can vary, however, from the flat, vertically sided feature, eg, the Niagara Escarpment, to a cuesta (with a steep scarp face and gentle dip face), or to a hogback ridge in which both faces are equally inclined.
See also PLATE TECTONICS.
Author R.B. BRYAN