Natural Disasters

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Natural Disasters

• By Patrick L. Abbott

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Chapter 6

• Volcanoes

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Overview

• Anatomy of an Eruption
• Chemical and Mineral Composition of Magmas
• Temperature, Gas Content, and Viscosity of Magmas
• Volcanic Landforms
• Eruptive Styles
• Collapse Calderas

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Anatomy of an Eruption

• Springs
• Geysers
• How a Geyser Erupts
• Pores
• How a Volcano Erupts
• Viscosity

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Chemical and Mineral Composition of Magmas

• Minerals
• Crystallization
• Rocks
• Plutonic rocks
• Volcanic rocks

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Chemical and Mineral Composition of Magmas (cont.)

• Volcanic Materials
• Pyroclastic
• Pahoehoe
• aa
• Pillow lava
• Obsidian
• Pumice

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Temperature, Gas Content, and Viscosity of Magmas

• Basalt
• Andesite
• Rhyolite

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Volcanic Landforms

• Sills
• Dikes
• Cinder Cones (Basaltic to Andesitic)
• Volcanic plug
• Stratovolcanoes (Andesitic to Rhyolitic)
• Composite volcanoes
• Shield Volcanoes (Basaltic)

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Eruptive Styles

• Icelandic-type
• Fissures
• Lava Flows of 1973
• Hawaiian-type
• Strombolian-type
• Volcanian-type

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Eruptive Styles (cont.)

• Vesuvian-type
• Vesuvius, 79 C.E.
• Pyroclastic flows
• Lahars
• Plinian-type
• Plinian eruption
• Pelean-type

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Collapse Calderas

• Crater Lake (Mount Mazama), Oregon
• Caldera
• Krakatau, Indonesia, 1883
• Santorini and the Lost Continent of Atlantis