Sevier orogeny Sevier orogeny The Sevier orogeny was a mountain-building event that affected western North America from Canada to the north to Mexico to the south. The Sevier orogeny was the result of convergent boundary tectonic activity between approximately 140 million years (Ma) ago and 50 Ma. The Sevier River area of central Utah is the namesake of this event. This orogeny was produced by the subduction of the oceanic Farallon Plate underneath the continental North American Plate. Crustal thickening that led to mountain building was caused by a combination of compressive forces and conductive heating initiated by subduction in the Sevier
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