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
Sunsás orogeny active during four separate phases: Sunsás orogeny The Sunsás orogeny was an ancient orogeny active during the Late Paleoproterozoic and Mesoproterozoic and currently preserved as the Sunsás orogen in the Amazonian Craton in South America. About 85% of the belt is covered by Phanerozoic sediments. Among the remaining 15% of the orogen exposed at surface the best outcrops lies around the Bolivia-Brazil border. It is thought that the original orogen once spanned an area from Venezuela to Argentina and Paraguay. The western and southeastern fringes of the Sunsás orogen have been incorporated into the Andean orogeny and the Brasiliano orogeny