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Objective: SWBAT identify and describe factors effecting volcano production IOT differentiate amongst 3 types of volcanoes. Drill: Where are three areas you would expect to find volcanoes on the earths surface?.
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Objective: SWBAT identify and describe factors effecting volcano production IOT differentiate amongst 3 types of volcanoes Drill: Where are three areas you would expect to find volcanoes on the earths surface?
Volcanoes refer to areas in the Earths crust that release gasses, molten rock, or ash. Alaska’s Aleutian Islands May 23,2006 Yellowstone National Park Hot spring MELIPEUCO, Chile, July 13 2008
From our definition of volcano we can reason that they would be found along plate boundaries and over hotspots where the inner earth is exposed to the Earths surface.
Volcanoes are classified by how they are formed. There are 5 main types. • Shield Volcanoes • Cinder Volcanoes • Composite Volcanoes • Calderas • Lava Plateau
Shield Volcanoes 12,188.3 feet • Characterized by having broad based and gently sloping sides. • Caused by the flow of low viscosity Mafic magma • Since the magma is thin, gasses can readily escape and eruptions are not explosive • Extrude basaltic lava • Because of the broad base, these volcanoes can grow to be very high
Cinder Cones • Characterized by a cone shaped mound with a oval base • Caused by lava fragments that explode outward and harden before they hit the ground • Relatively small • Generally form in groups or on the sides of larger volcanoes • Slope of these volcanoes are usually steep
Composite Volcanoes -Composed of alternating layers of rock fragments, ash, and lava. Cycling quiet lava flows interrupted by explosive eruptions of pyroclastic material -Are large volcanoes Also known as Strato-volcanoes