GEOL 1020 Lecture Notes - Lecture 22: Cenozoic, Laramide Orogeny, Yellowstone Caldera
7 Dec 2017
School
Department
Course
Professor
Document Summary
Off topic yellowstone is a supervolcano. Scientific monitoring for the last 30 years suggests geologic activity is constant, and an eruption is unlikely in the next 1,000-10,000 years. The last lava flow was 70,000 years ago. Deformed mixture of rocks, comprised of deep ocean sediments (muds and graywackes) mixed with bits of oceanic crust scraped from the subducting plate, that all gets metamorphosed. Accretionary wedge: due to huge compressional forces, slices of melange and seafloor break off of the descending plate and pile up along thrust faults (textbook pg. Name comes from the greenish color of the rock. Pieces of oceanic crust and upper mantle (ie, a snippet of the moho) that are thrust onto the edge of continental plates. An ophiolite is a sequence of rock types - an assemblage of mafic and ultramafic in association with sedimentary rocks. Moho is the boundary between the mantle and the crust.
