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,
Kibaran orogeny Kibaran orogeny The Kibaran orogeny is a term that has been used for a series of orogenic events in what is now Africa that began in the Mesoproterozoic around 1400 Ma and continued until around 1000 Ma when the supercontinent Rodinia was assembled. The term "Kibaran" has often been used for any orogenic rocks formed during this very extended period. Recently it has been proposed that the term should be used in a much narrower sense for an event around 1375 Ma and a region in the southeast of the Democratic Republic of the Congo (DRC). Regions that contain relics