GEO 1111 Midterm: GEO 1111 Midterm 2

• School: University of Ottawa
• Department: Geology
• Course: GEO 1111
• Professor: David Schneider

Document Summary

The earth is solid however it can be melted, this usually happens at tectonic plate melting the solid earth = igneous rocks, therefore volcanoes create igneous rocks boundaries. Molten material is less dense than surrounding rock = magma rises to surface. Under shallow pressures, gases start to form bubbles like carbonated beverage) Factors that determine the (cid:522)violence(cid:523) or explosiveness of a volcanic eruption. Typically, when the mantle rock that melts reaches the continental rock, which is felsic, it melts the crust and becomes more felsic. Rarely get felsic rock in the oceanic. Low gas [ ] = high viscous. When you get to 6% gas, thats considered very gaseous magma. If lava is low viscosity, then bubbles can escape = non-explosive eruption (effusive) - if lava is high viscosity, then pressure inside lava builds up = explosive eruption. As you walk across these rocks you say (cid:522)ah ah(cid:523) in pain)