Download CH. 9 Pre-Test

Earth Science Pretest
Chapter 9-Volcanoes
DO NOT WRITE ON THIS TEST!!
Place your answers on a separate sheet of paper!!
1. A theory that helps to explain the causes of both earthquakes and volcanoes is the theory
of
. [continental drift or plate tectonics]
2. Where are volcanoes most likely to form?
a. near the center of continents
b. in deep canyons
c. along plate boundaries
d. in mountainous areas
3. Volcanic activity is common along the Mid-Atlantic Ridge. This activity occurs at a
[convergent boundary, subducted plate, or divergent boundary]
4. Lava that is very runny probably
a. has a low silica content
b. is hotter than most lava
.
.
c. has been cooled below the surface
d. comes from explosive volcanoes
5. Magma that has a high silica content
.
a. has a thin, runny consistency
b. has a high carbon dioxide content
c. has a thick, runny consistency
d. has a thick, stiff consistency
6. Which of the following is forced to the Earth’s surface when a volcano forms? [steam, lava,
or magma]
7. An explosive volcanic eruption can give flight to solid rock fragments called
or pyroclastic material]
8. Silica-rich magma tends to harden in a volcano’s vent, often causing
a. nonexplosive eruptions
c. lava flow
b. explosive eruptions
d. earthquakes
.
9. Pyroclastic material is classified primarily by
.
a. particle size
c. temperature
b. color
d. iron content
10. Large amounts of volcanic ash can cause
a. destruction of trees and buildings
b. flooding
.
c. climatic changes
d. all of the above
11. When a volcano’s magma chamber empties and its roof collapses, a
a. cavity
c. crater
b. caldera
d. coprolite
Continued on the back!!
12. Layers of lava from nonexplosive eruptions build up to form a
.
a. caldera
c. composite volcano
b. shield volcano
d. volcanic block
forms.
. [lava flows
13. Pressure from the rock above keeps the rock in the Earth’s mantle in a
a. gaseous state
c. liquid state
b. solid state
d. border state
.
14. Nearly 75 percent of the world’s active volcanoes on land are found along a circuit of
tectonic plate boundaries known as
.
a. the Circle of Gold
c. Volcano Alley
b. the Bermuda Triangle
d. the Ring of Fire
15. Magma rises toward the surface of the Earth because it is
.
a. denser than the surrounding rock
c. less dense than the surrounding rock
b. full of air bubbles
d. the same density as the surrounding rock
16. A volcano can form at
.
a. a divergent boundary
b. a convergent boundary
17. Hot spots are directly above
c. neither of the above
d. both of the above
. [volcanic islands or mantle plumes]
18. Which lava erupts underwater, forming rounded lumps? [pahoehoe or pillow lava]
19. Most of the lava on the Earth’s continents erupts from long cracks in the Earth’s crust
called
. [fissures or crevasses]
20. As you move northwest through the Hawaiian Islands, the age of the islands increases. The
older islands are northwest of the newer islands because they
.
a. aged faster than those to the east
b. formed first and then moved away from the hot spot
c. were made of less lava than the southeastern islands
d. formed from old, recycled, silica-rich magmas