Geography 2152F/G Lecture Notes - Lecture 8: Mount Pinatubo, Lateral Eruption, Return Period
10 Dec 2017
School
Department
Course
Professor
Document Summary
Types of molten rock: magma, found deep within crust and upper mantle, lava, found flowing from an erupting volcano, lava= magma on earth"s surface. Viscosity: magma also contains small amounts of gases (water vapour and carbon dioxide, volcanoes have different shapes based on the chemistry and viscosity of their magma, magma viscosity determined by silica content and temperature. St. helens: volcanic dome, highly viscous rhyolite magma, steep sided mounts that form around vents, cinder cone, relatively small volcanoes composed of small pieces of tephra, round to oval shaped and contain a crater at the top, mexico. Maars: def: circular volcanic craters produced by an explosive eruption and filled with water, caused by groundwater coming in contact with magma creating an explosion, latin mare sea. Ice-contact volcanoes: some volcanoes erupt beneath or against glaciers, eruptions melt huge quantities of ice producing floods known as j kulhaups, when lava contacts glaciers cools to form pyroclastic rock, evidence of the mt.
