Name ______Class ______Date ______
Chapter 10 Volcanoes and Other Igneous Activity Study Guide
Multiple Choice
Write the letter that best answers the question or completes the statement.
1. Magma forms when solid rock in the crust and uppermantle
a. partially melts.c. vaporizes.
b. crystallizes.d. cools.
2. Which type of landform develops at plate boundaries whereone oceanic plate descends beneath another?
a. rift valleyc. mountain formed by a batholith
b. volcanic island arcd. lava plateau
3. At divergent plate boundaries in the ocean, magma risesand melts because of
a. higher temperatures at the surface.
b. a decrease in pressure.
c. intrusive plutons at the boundary.
d. increased silica content of magma.
4. What are the landforms at divergent ocean plateboundaries?
a. mid-ocean ridgesc. continental arcs
b. island arcsd. ocean trenches
5. Most intraplate volcanic activity occurs where
a. oceanic plates diverge.
b. mantle plumes rise toward the surface within a plate.
c. hot magma descends into the mantle under a plate.
d. oceanic and continental plates converge.
6. As the temperature of lava increases,
a. its viscosity decreases.c. its viscosity increases.
b. it begins to harden.d. it can flow a much shorter distance.
7. What type of volcano is fairly symmetrical and has bothlayers of lava and pyroclastic deposits?
a. a cinder cone volcanoc. a pyroclastic volcano
b. a shield volcanod. a composite cone volcano
8. What is a caldera?
a. a fiery volcanic explosionc. a large depression in a volcano
b. a type of volcanod. a very large volcanic bomb
9. Which of the following is NOT a factor in how violently orquietly a volcano erupts?
a. magma’s compositionc. magma’s concentration of dissolved gases
b. magma’s temperatured. magma’s depth inside a volcano’s vent
10. What is a volcanic bomb
a. a very violent volcanic explosion
b. a particle larger than 64 mm in size ejected as glowing lava
c. a pocket of gas that is released suddenly
d. a tiny particle of ejected rock less than 64 mm in size
11. The particles produced in volcanic eruptions are called
a. pyroclastic materials.c. calderas.
b. laccoliths.d. volcanic stocks.
12. Which of the following plays a major part in determiningthe form of a volcano?
a. elevation above sea levelc. local soil type
b. magma compositiond. nearness of other volcanoes
13. Most shield volcanoes have grown from the ocean floorto form
a. islands.c. canyons.
b. dikes.d. tectonic plates.
14. The broad, slightly dome-shaped volcanoes of Hawaii are
a. composite cone volcanoes.c. shield volcanoes.
b. pyroclastic volcanoes.d. cinder cone volcanoes.
Completion
Complete each statement using the word bank provided.
15. Descending into Earth’s interior, temperature, as well as pressureon rock, ______.
16. Where slabs of oceanic lithosphere are subducted undercontinental lithosphere, a ______volcanic arccan form.
17. Gases escaping from volcanoes often include ______, ______, nitrogen, and sulfur,with lesser amounts of chlorine, hydrogen, and argon.
18. The accumulation of fluid basaltic lava produces a(n) ______volcano.
19. The most explosive volcanic eruptions come from ______volcanoes.
20. The magma that feeds most volcanoes moves from a magmachamber toward the surface through
______.
21. Rhyolitic lavas are very viscousbecause they have a high ______content.
22. A volcanic ______forms when the rock in a pipe isresistant to erosion and remainsstanding above the surface afterthe rest of the volcano has wornaway.
23. Another name for a compositecone volcano is a(n) ______.
Short Answer
In complete sentences, write the answers to the following questions.
24. Describe three factors that affect how magma forms.
25. How is the location of most of Earth’s volcanoes related to plateboundaries?
26. Why do volcanoes with very viscous magmas erupt the mostexplosively?
Use the table to answer the following two questions.
27. Using Tables and Graphs Which type of volcano will have thequietest type of eruption? Explain your answer.
28. Why is the type C volcano likely to explode violently?
29. Describe the shape and composition of a cinder cone.