Andean orogeny Andean orogeny The Andean orogeny () is an ongoing process of orogeny that began in the Early Jurassic and is responsible for the rise of the Andes mountains. The orogeny is driven by a reactivation of a long-lived subduction system along the western margin of South America. On a continental scale the Cretaceous (90 Ma) and Oligocene (30 Ma) were periods of re-arrangements in the orogeny. Locally the details of the nature of the orogeny varies depending on the segment and the geological period considered. Subduction orogeny has been occurring in what is now western South America since the break-up
Cadomian Orogeny typical structure. After the orogeny, continental sediments were washed on top of the deformed Cadomian rocks. They include conglomerate and sandstone in Brittany, Jersey and Alderney. The Cap Frehel red beds are dated at . These post orogeny deposits were dumped from braided stream channels. The basins for these sediments followed the structural grain in the Cadomian Orogeny. There are two overall models for the formation of the Cadomian Orogeny. Firstly by Jean-Pierre Brun & P. Bale that compression to the south west of a volcanic arc and back arc basin onto the edge of the continent at the St