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Correctly rank the these three magmas in order of increasing viscosity: andesitic, mafic, felsic.

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mafic, and...

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Volcanic bombs originate ________.


A) as laser-guided, granite blocks launched from a supersonic jet
B) as blocks of volcanic rock ejected from an erupting volcanic crater
C) as erupted magma blobs that partly congeal before falling to the ground
D) as ash particles that join together in the eruptive plume and fall as cobble-sized objects

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The eruptions of the Hawaiian volcanoes may be described as explosive in comparison to the 2010 Mount Merapi eruption.

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The 1991 Pinatubo eruption in the Philippines caused global temperatures to drop over the next year.What caused this phenomenon?


A) The eruption added large amounts of carbon dioxide to the atmosphere.
B) The eruptive cloud destroyed parts of the Earth's protective ozone layer.
C) Radioactive atoms blown into the atmosphere froze as they decayed.
D) Sulfur dioxide was released and formed aerosols in the atmosphere.

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Consider the differences in shape and size of shield volcanoes, cinder cones, and composite volcanoes.How does the relative size and shape of each reflect variations in eruptive characteristics (duration, types of materials, composition of lava, etc.)? Which eruptive characteristics are common to all volcanoes and which ones are unique to each?

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Shield volcanoes and composite volcanoes...

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Fluid mafic eruptions on sloping seafloor leaves piles of glassy skinned irregular shaped deposits called ________.

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pillows, p...

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Approximately how long has B.C.'s Mt.Garibaldi, in the Canadian part of the Cascades volcanoes, been dormant?


A) since May 1980
B) since 1967
C) since 1912
D) since the last Ice Age

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A magma's viscosity and tendency to cause explosive eruptions depends on its composition, temperature, and volatile gas content.

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Ash and lapilli are different sized pyroclastic particles, smaller and larger than 2 mm respectively.

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What is the most abundant type of magma erupted at oceanic spreading centres?


A) mafic
B) pyroclastic
C) andesitic
D) felsic

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What destroyed the city of St.Pierre, Martinique in 1902?


A) mudflows
B) mafic lava flows
C) heavy ashfall
D) a nuée ardente

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Word Analysis Questions Examine the words and/or phrases for each question below and determine the relationship among the majority of words/phrases. -Choose the option that does not fit the pattern. A)Deccan Traps B)Minus Basin C)Columbia Plateau D)Black Tusk

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For the following items, please choose from one of the following answers. -________ small basaltic cones built during one, short, eruptive episode


A) shield volcanoes
B) composite/stratovolcanoes
C) cinder cones

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Obviously large volumes of lava and pyroclastic debris pose serious hazards to humans.What are some of the more indirect hazards associated with volcanic eruptions? Which of these indirect hazards are more likely to be overlooked when planning for potential eruptions in a given area? Why?

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Air pollution by pyroclastics (blocking ...

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Which one of the following statements is false?


A) Melting temperatures of silicate rocks increase with increased pressure.
B) Melting temperatures of silicate rocks are lowered by small amounts of water.
C) Mafic magmas in general have higher temperatures than felsic magmas.
D) When magma reaches the surface, its dissolved gas content increases.

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A relatively small, summit depression on a volcano, marking a former eruptive vent, is called a what?

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What volcanic rock, typically of rhyolitic composition, forms by compaction and squeezing together of particles in a hot, pyroclastic-flow deposit?

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How quickly are volcanoes like Paricutin in Mexico or Mt.Edziza in central B.C.built?


A) in a single eruption within a few hours
B) in a single eruption within a few days
C) in a single eruptive cycle lasting about a year or more
D) in several eruptive cycles over 10's of thousands of years

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Repeated eruptions of relatively fluid lava from fissures (Columbia River Plateau, Deccan Traps)can eventually cause an area to be covered by flood basalts.

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What are the smaller secondary volcanic vents on a large composite volcano like Mt.Etna called?

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