Volcano Review With Answers

Name ___Answer Key_______ Period _____ Assignment # __

Vocabulary Review: 1. 2. 3. 4. 5. 6. 7. 8.

Basaltic volcano with gently sloping sides. Shield Volcano Volcano formed from alternating layers of lava and tephra Composite (Strato) Volcano A secondary vent that emits only gases _____Fumarole______________________ Smooth lava that sometimes cools with a ropey texture ___Pahoehoe___________ Mixture of volcanic ash, eroded land and water the flows into valleys _ Lahar Hot area in Earth’s mantle that melts rock into magma Hot Spot Mountain that forms from layers of lava and ash Volcano A smaller secondary volcano built on the side of or near the main volcano, but sharing the same conduit to the magma chamber ___Parasitic Cone_______________ 9. Large opening caused by the collapse of the top of a volcano Caldera 10. Ash and cinders blown violently out of volcanoes Tephra 11. Opening at the top of a volcano’s vent Crater 12. Lava suddenly cooled by water Pillow Lava 13. The “neck” of the volcano, connects the magma chamber to vent Conduit 14. The reservoir located under the volcano where magma collects __Magma Chamber_____ 15. A long crack from which lava flows ___Fissure_______________________ 16. Rough, jagged lava that is thick and slow moving __AA Lava______________ 17. A scientists who studies volcanoes __Volcanologist______________________ 18. Steep-sided volcano made of tephra ____Cinder Cone ___________________ Volcano Tephra Conduit Shield volcano AA

Hot spot Fumarole Volcanologist Crater Pillow lava

Composite volcano Parasitic Cone Fissure Pahoehoe Lahar

Types of Tephra: _Lapilli________________ walnut sized rocks _Cinder_______________ pea sized / gravel sized _Volcanic Dust_________ smallest particles that come from a volcano _Bomb_______________ can be up to 4+ feet in diameter _Volcanic Ash__________ .25 to .5 cm in diameter

Magma Chamber Cinder cone Caldera

Concept Review: 1. Identify each form of volcano and then fill in the chart with the appropriate information about each form.

Form of Volcano Figure 1: Shield Volcano Figure 2: Cinder Cone Figure 3: Compostie(Strato)

Type of Magma or Composition

Shape of Volcano

Layers of Lava Loosely Packed Cinders

Wide Base; Gentle Slope Narrow Base Steep Sides

Alternating layers of Lava and Tephra

Tall; Snowcapped Mountain

Materials in volcano Hot, Thin Basaltic Lava Thick Lava rock fragments Thick Granitic lava; lots of silica; large rock fragments

2. What is the relationship between the amount of gases in magma and the explosiveness of a volcanic eruption? When rocks melt into magma gasses are released. The more gasses released, the more pressure builds up. The more gasses and the more pressure, the greater the exlposiveness of the eruption. 3. What are the three places where volcanoes are found. Give an example of each. __Some volcanoes are found at divergent boundaries and can form volcanic islands (Iceland); Some volcanoes are found at convergent boundaries (Pacific Ring of Fire, Cascade Mountains); Lastly, some volcanoes are found at “hot spots” places where the magma comes up through the crust (Hawaiian Islands)_____ 4. What are the three stages of the life of a volcano? _The three stages of the life of a volcano are: Active (Mt. St. Helens); Dormant (sleeping) (Mt. Reiner) and Extinct (Mt. Mazama-Crater Lake)_____________________________ 5. Describe the activity that will be observed around an active volcano just before it erupts. Some pre-eruption activity of a volcano are: increase in temperature of the cone; earthquakes; swelling of the cone; small release of gas; small release of ash; melting of the snow at the top of the mountain.___

Label the parts of the volcano on the diagram below: Crater Gas/Ash Cloud Parasitic Cone

Vent Lava Flow Conduit

Mantle

Gas/Ash Cloud