Alleghanian orogeny the Allegheny and Cumberland Plateau, which in some areas are popularly called mountains, but are actually simply uplifted and eroded plateaus. A portion of the Alleghanian mountain system departed with Africa when Pangaea broke up and the Atlantic Ocean began to form. Today, this forms the Anti-Atlas mountains of Morocco. The Anti-Atlas have been geologically uplifted in relatively recent times, and are today much more rugged than their Alleghanian relatives. Alleghanian orogeny The Alleghanian orogeny or Appalachian orogeny is one of the geological mountain-forming events that formed the Appalachian Mountains and Allegheny Mountains. The term and spelling Alleghany orogeny was
Gondwanide orogeny orogeny is the successor to the Neoproterozoic-Paleozoic Terra Australis orogeny in Gondwana. Following the Gondwanide orogeny southwestern Gondwana entered a period of extensional tectonics and crustal thinning leading to formation of various rift basins (e.g. Cuyo Basin) in the Triassic. Gondwanide orogeny The Gondwanide orogeny was a orogeny active in the Permian that affected parts of Gondwana that are by current geography now located in southern South America, South Africa, Antarctica, Australia and New Guinea. The zone of deformation in Argentina extends as a belt south and west of the cratonic nucleus of Río de la Plata–Pampia. The deformation of