Cadomian Orogeny Cadomian Orogeny The Cadomian Orogeny was a tectonic event or series of events in the late Neoproterozoic, about 650–550 Ma, which probably included the formation of mountains. This occurred on the margin of the Gondwana continent, involving one or more collisions of island arcs and accretion of other material at a subduction zone. The precise events, and geographical position, are uncertain, but are thought to involve the terranes of Avalonia, Armorica and Iberia. Rocks deformed in the orogeny are found in several areas of Europe, including northern France, the English Midlands, southern Germany, Bohemia, southern Poland and the southwest Iberian
Rangitata Orogeny This collision lasted for 50 million years. However, the wet sediments could not just keep piling up. After 50 million years, there was simply too much rock and a 'log jam' in the process was formed. The rocks were squeezed together as they broke and crumpled up. As the compression intensified, the strata were slowly pushed up, creating new land. The collision was also causing a great thickening of the crust, pushing the rocks down into the top of the mantle. The high pressures and temperatures of this occurrence metamorphosed the lower rocks into the Haast Schists. Rangitata Orogeny The