Orogeny millions of years and build mountains from plains or from the seabed. The topographic height of orogenic mountains is related to the principle of isostasy, that is, a balance of the downward gravitational force upon an upthrust mountain range (composed of light, continental crust material) and the buoyant upward forces exerted by the dense underlying mantle. Frequently, rock formations that undergo orogeny are severely deformed and undergo metamorphism. Orogenic processes may push deeply buried rocks to the surface. Sea-bottom and near-shore material may cover some or all of the orogenic area. If the orogeny is due to two continents colliding,
Petermann Orogeny Petermann Orogeny The Petermann Orogeny was an Australian intracontinental event that affected basement rocks of the northern Musgrave Province and Ediacaran (Proterozoic) sediments of the (now) southern Amadeus Basin between ~550-535 Ma. The remains are seen today in the Petermann Ranges. Prior to the Petermann Orogeny, which resulted in exhumation of the Musgrave Block, the Amadeus Basin was contiguous with the Officer Basin in South Australia. The extent and effect of the Petermann Orogen appears to be relatively confined, occurring most pervasively within the central northern-Musgrave Block. Here, older Musgravian (~1200-1150 Ma) fabrics are partially to completely overprinted by sub-eclogite-facies