GEL 25 Lecture Notes - Lecture 13: Stratovolcano
Document Summary
Volcano most likely to erupt in the near future. Volcanic dome: roughly circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Magma is underground and lava is above the surface. Last major eruption 5700 yrs ago with many smaller eruptions since. Composed of stacked layers of hundreds of lava flows. Consists of snow and ice-covered crests of mount rainier and the overlapping summit craters with their rims of exposed rock. 25 alpine glaciers radiate downslope from the crest. Largest single-peak glacier system in lower 48. Accumulation: occurs as snow is transformed to denser ice by compaction from the weight and pressure of overlying snow, accompanied by the removal of air from between snow crystals (head of glacier) Ablation: is the removal of ice near the toe of glaciers, typically by melting, sublimation (the evaporation of ice directly into water vapor), and calving" of icebergs into water (toe of glacier)
