section 13-2 review
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Section 13-2 Review. Page #330:1-8. #1. Summarize the difference between mafic and felsic magma. Mafic Magma magnesium & iron dark less viscous. Felsic Magma silica & feldspars light more viscous. #2. Explain how the composition of magma affects the force of volcanic eruptions. - PowerPoint PPT PresentationTRANSCRIPT
Section 13-2 ReviewPage #330:1-8
#1
Summarize the difference between mafic and felsic magma.
Mafic Magma magnesium & iron dark less viscous
Felsic Magma silica & feldspars light more viscous
#2
Explain how the composition of magma affects the force of volcanic eruptions.
More viscous magma traps gases more easily than less viscous magma, which may lead to more explosive eruptions.
#3
Compare three major types of lava flows.
• Pahoehoe – ropy • Aa – jagged • Blocky Lava – large chunks
Pahoehoe
Aa
#4
Define pyroclastic material, and list three examples.
Pyroclastic material consists of fragments of rock that form during an explosive eruption.
Pyroclastic Materialvolcanic ash/dust
lapilli
volcanic bombs
Volcanic Ash
Bomb
#5Identify the three main types of volcanic cones.
shield volcanocinder conescomposite volcano
Types of Volcanoes
Shield Volcano
Mauna Loa - Hawaii
Cinder Cone
http://video.google.com/videoplay?docid=5804326697533034741&q=cinder+cone+eruption&hl=en
Composite Volcano
http://video.google.com/videoplay?docid=3977416382972126736&q=mt+st+helens+eruption&hl=en
#6
Describe how calderas form.
A caldera forms when the magma chamber of a volcano empties, causing the volcanic cone to collapse in upon it, or when magma is ejected violently and the cone is destroyed.
Caldera
Crater Lake
#7
List three events that may precede a volcanic eruption.
earthquake activity
rock temperatures increase
volcano area bulges
#8Why would a sudden increase of earthquake activity around a volcano indicate a possible eruption.
Sudden earthquake activity could be caused by magma moving upward through the rock around the volcano.
The End
On “Io” a moon of Jupiter