1. Natural Disasters By: Patrick L. Abbott

2. Chapter 6 Volcanoes

3. Overview zAnatomy of an Eruption zChemical and Mineral Composition of Magmas zTemperature, Gas Content, and Viscosity of Magmas zVolcanic Landforms zEruptive Styles zCollapse Calderas

4. Anatomy of an Eruption zSprings zGeysers zHow a Geyser Erupts yPores zHow a Volcano Erupts yViscosity

5. Chemical and Mineral Composition of Magmas zMinerals zCrystallization zRocks zPlutonic rocks zVolcanic rocks

6. Chemical and Mineral Composition of Magmas (cont.) zVolcanic Materials yPyroclastic yPahoehoe yaa yPillow lava yObsidian yPumice

7. Temperature, Gas Content, and Viscosity of Magmas zBasalt zAndesite zRhyolite

8. Volcanic Landforms zSills zDikes zCinder Cones (Basaltic to Andesitic) yVolcanic plug zStratovolcanoes (Andesitic to Rhyolitic) yComposite volcanoes zShield Volcanoes (Basaltic)

9. Eruptive Styles zIcelandic-type yFissures yLava Flows of 1973 zHawaiian-type zStrombolian-type zVolcanian-type

10. Eruptive Styles (cont.) zVesuvian-type yVesuvius, 79 C.E. yPyroclastic flows yLahars zPlinian-type yPlinian eruption zPelean-type

11. Collapse Calderas zCrater Lake (Mount Mazama), Oregon yCaldera zKrakatau, Indonesia, 1883 zSantorini and the Lost Continent of Atlantis