Volcanoes

- explosive, lava flows

Textures- lava flows pahoehoe, aa, rock texture, vesicular texture; glassy texture, obsidian, pillow lava; explosive textures, ash, pyroclastic texture, vesicular texture, pumice (vesicular)

Controls on explosiveness: gas content (H₂0, CO₂, N, SO₂, H₂S), magma viscosity, temperature, SiO₂ content

Types of volcanos: shield volcanoes, cinder cones, composite volcanos, lahars, pyroclastic flows, calderas

What factors control the explosiveness of a magma? Which magmas are most viscous? Which are least viscous? How does this affect the style of volcanism?

Compare and contrast shield volcanoes, cinder cones, and composite volcanoes. Give one example of where each type can be located.

Describe four textures associated with volcanic rocks, and explain how each texture forms.

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