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42 Cards in this Set
- Front
- Back
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Label a Volcano
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Magma, Magma Chamber, Side Vent, Pipe, Vent, Crater, Lava, Lava Flow
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How do volcanoes form?
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Subduction occurs and the crust melt into magma that erupts to for m a volcano
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Identify the 3 types of volcanoes
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Shield, Composite, Cinder-Cone
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How a Shield Volcano Forms
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some place on Earth's surface, thin layers of lava pour out of a vent and harden on top of other layers. creates a wide, gently sloping mountain
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How a Composite Volcano Forms
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sometimes, lava flows alternate with explosive eruptions of ash, cinder, and bombs creating a composite volcano
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How a Cinder-Cone Volcano Forms
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If a volcano's lava is thick and stiff, it may produce ash, cinders, and bombs which pile up around the vent in a steep, cone-shaped pile.
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What eruption causes a shield volcano?
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Quiet
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What eruption causes a composite volcano?
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Both Quiet and Explosive
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What eruption causes a cinder-cone volcano?
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Explosive
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Where do find each type of volcano?
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Shield in Hawaii. Composite in Mount Hood in Oregon. Cinder-cone in Sunset crater in Arizona.
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<---->
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Divergent Boundary
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--> <--
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Convergent Boundary
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Volcanic Particles
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Dust-Grains of sand, rice
Ash-Flour Cinders-Golf Balls, Pebbles Bombs-Boulders, baseballs, car |
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Silica
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formed from oxygen and silicon. abundant
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Silica content
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more=thicker, lighter, sticky, forms rhyolite(granite) when dry, pummus, obsidian
less= thinner, darker, flows better, rock like basalt |
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Pummus
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forms when gas bubbles are trapped in cooling lava, leaving spaces in the rock.
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Sill
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slab of volcanic rock forms when magma squeezes between layers of rock
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Dikes
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slab of volcanic rock forms when magma forces itself across rock layers
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Batholiths
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mass of rock formed when a large body of magma cooled inside the crust
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Caldera
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the large hole at the top of a volcano formed when the roof of the volcano's magma chamber collapses
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Crater
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bowl-shaped area that forms around a volcano's central opening
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Volcanic Neck
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deposit of hardened magma in a volcano's pipe
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Hot Spot
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an area where magma from deep within the mantle melts through the crust above it.
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Geyser
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A fountain of water and steam that builds up pressure underground and erupts at regular intervals
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Island Arc
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A string of islands formed by the volcanoes along a deep ocean trench
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Ring of Fire
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A major belt of volcanoes that rims the Pacific Ocean
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Pyroclastic Flow
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The expulsion of ash, cinders, bombs, and gases during an explosive volcanic eruption
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Dormant
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Said of a volcano hat does not show signs of erupting in the near future
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Active
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Said of a volcano that is erupting or has shown signs of erupting in the near future
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Extinct
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Said of a volcano that is unlikely to erupt again
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Geothermal Energy
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energy from water or steam that has been heated by magma
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Pahoehoe
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a hot, fast moving type of lava that hardens to form smooth rope like coils
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AA
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a slow moving type of lava that hardens to form rough chunks. slower than pahoehoe
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How does the release of trapped gases in magma cause a volcano to erupt?
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gases are under lots of pressure. magma rises to the surface, the pressure decreases and the gases begin to separate. magma finds opening the gases rush out & carry the magma w/ them
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You live on a large volcanic island not far from an active volcano. Besides damage from lava, what other hazards might affect your town and it's people?
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an eruption could cause landslides or avalanches of mud, melted snow or rock. If an explosive eruption occurs, clouds of hot burning gases could injure people. ash could bury the village, damage crops, and clog car engines.
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What kind of volcanic activity might you expect to observe at or near a dormant volcano?
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It is "asleep" but all the pressure builds up and it could erupt anytime and probably cause geysers from hotness. a dormant volcano may not erupt for 100s of yrs. however the volcanoes body of magma may heat nearby groundwater creating hot springs or geysers
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What kind of eruption is likely to occur in a volcano having magma that is low in silica?
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In some liquids there is a greater degree of friction among the liquid's particles. these liquids have higher viscosity than liquids whose particles have a lesser degree of friction.
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Why do different viscosities?
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Friction between the particles or molecules in some liquids, there is a greater degree of friction among the liquids particles. these liquids have higher viscosity than liquids whose particles have a lesser degree friction
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Dome Mountains
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smaller bodies magma=dome mountain. forms when rising magma is blocked by horizontal layers of rock. magma forces layers to bend upward into a dome shape.
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Lava Plateau
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some eruptions form high, level areas. lava flows out of several long cracks. thin runny lava travels far before cooling and solidifying repetitively lava flows on top of each other forming plateaus.
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Is a volcanic eruption likely to occur on the east coast of the US?
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No, there are no plate boundaries located close by or volcanoes
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Compare the way an island arc forms with the way a hot spot volcano forms
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an island arc forms at a converging boundary between two oceanic plates where one subducts under the other and creates a deep ocean trench. a hot spot forms in a continental or oceanic plate where magma from deep within he mantle melts through the crust. Hot spots lie in the middle of plates and do not result from subduction
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