Sevier orogeny region which caused folding and thrusting. The mountains that were formed as a result were located in western Utah and eastern Nevada. The size, shape, and depth of the thrust faults created in the Sevier event are determined by seismic studies and deep well data because they are mostly still buried by overlying rock and sediment. The Sevier and Laramide orogenies ended when subduction along the western edge of North America was overcome by western extension of the North American Plate to start the Basin and Range Orogeny. The well known and familiar Basin and Range faults cut the older
Andean orogeny were inverted in the Miocene. After a period of quiescence the Agrio fold and thrust belt resumed limited activity in the Eocene and then again in the Late Miocene. In the south of Mendoza Province the Guañacos fold and thrust belt (36.5° S) appeared and grew in the Pliocene and Pleistocene consuming the western fringes of the Neuquén Basin. The early development of the Andean orogeny in southernmost South America affected also the Antarctic Peninsula. In southern Patagonia at the onset of the Andean orogeny in the Jurassic, extensional tectonics created the Rocas Verdes Basin, a back-arc basin whose southeastern