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
Hunter-Bowen orogeny Hunter-Bowen orogeny The Hunter-Bowen Orogeny was a significant arc accretion event in the Permian and Triassic periods affecting approximately 2,500 km of the Australian continental margin. The Hunter-Bowen Orogeny occurred in two main phases, a Permian accretion of previously formed passive-marginal Devonian and Carboniferous sediments in the Hunter region and mid-west region of what is now New South Wales, separated by rifting, back-arc volcanism and a later Permian to Triassic event resulting in arc accretion and metamorphism during a subduction event. The Hunter-Bowen Orogeny has resulted in the New England Fold Belt, a tectonic accretion of metamorphic terranes and mid-crustal