The Nevadan Orogeny was a major mountain building event that took place along the western edge of ancient North America between the Mid to Late Jurassic (between about 180 and 140 million years ago).[1] The Nevadan orogeny was the first of three major mountain building episodes to transform Western North America between the Late Mesozoic and Early Cenozoic Eras, the latter two being the Sevier orogeny and Laramide orogeny, chronologically. The Nevadan orogeny is unique among the three in that it produced Andean-style stratovolcanoes, possibly reaching up to 20,000 feet (6,100 m), while the other orogenies were compressional events. The massive series of exposed batholiths that currently make up most of the high Sierra Nevada was formed during this event.


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