EARTHSC 1105 Lecture Notes - Lecture 20: Crater Lake National Park, Mount Mazama, Plate Tectonics
Document Summary
Mountaintop lake -6,178 ft. above sea level. Deepest lake in us 1,949 ft. deep. What is a tectonic plate: contiguous segment of crust. Stratavolcano volcano formed from layers of ash and lava. Active volcano last erupted ~ 5,700 bce. Rhyolite extrusive igneous rock of felsic composition. Andesite extrusive igneous rock of intermediate composition: slab pull the gravitational pull of subducted crust, convection the push of middle upwelling at divergent boundaries, convergent collisional boundary. Subductoin the downward of sideways movement of a tectonic. Oceanic / continental the oceanic plate is subducted under the. Plate tectonic boundaries plate beneath another into the mantle. Rates of movement: pacific plate ~10cm / year continental plate. Cinder cone a volcanic cone formed by the accumulation of ash. Dike igneous intrusion which cuts across layers. Receives 44 feet of snow / year. Crater lake: highest snowfall in 1932-1933 -73 feet of snow.