Download DR 9.1a- Volcanic Eruptions

Name
Class
Date
DR 9.1a- Volcanic Eruptions
1. Volcanic eruptions can be
times stronger than the
explosion produced by the first atomic bomb.
2. What is magma?
3. Magma that flows onto the Earth’s surface is called
.
4. Volcanoes are described as ____________________________________________.
NONEXPLOSIVE ERUPTIONS
5. Which of the following can happen during nonexplosive eruptions?
a. violent explosions
c. huge lava flows
b. tons of rock blast into air
d. fire shooting into the air
6. The most common type of volcanic eruption is
.
7. Large areas of the Earth are covered with
from
nonexplosive eruptions.
8. Volcanic eruptions occur on land and on the
floor.
EXPLOSIVE ERUPTIONS
9. Which of the following would you expect to see during an explosive
volcanic eruption?
a. calm lava flows
b. hot debris, ash, and gas shooting into the air
c. a rainbow
d. lava fountains
10. In volcanic eruptions, molten rock is blown into dust-sized particles
called
.
11. How quickly can an explosive eruption demolish a mountainside?
12. During an explosive eruption, where do larger pieces of debris fall?
WHAT IS INSIDE A VOLCANO?
Match the definition with the correct term. Write the letter in the space provided.
13. hot liquid material below the Earth’s surface
14. an opening in the Earth’s crust
15. molten material flowing on Earth’s surface
a. vent
b. magma
c. lava
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt Science and Technology
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Volcanoes
Name
WHAT MAKES UP MAGMA?
16. Silica-rich magma
a. has a thin, runny consistency.
b. allows gases to escape easily.
c. causes explosive eruptions.
d. is rarely associated with explosive eruptions.
17. The more water contained in the magma, the
the
chances an explosive eruption will occur.
WHAT ERUPTS FROM A VOLCANO?
18. The main product of a nonexplosive eruption is
.
19. The main product of an explosive eruption is
20. Pyroclastic material forms when
.
is blasted into the
air and hardens.
Match the description with the correct term. Write the letter in the space provided.
21. forms underwater in rounded lumps
a. aa lava
22. flows slowly, like dripping wax
b. pillow lava
23. has a brittle, jagged crust
c. pahoehoe lava
24. cool, stiff lava that forms jumbled heaps
d. blocky lava
25. The viscosity of lava tells how
the lava is.
26. Lava that pours out quickly to form a brittle crust is called _____________lava.
27. Lava that flows slowly and has rounded wrinkles on its glassy surface is
called
lava.
Match the description with the correct term. Write the letter in the space provided.
28. large blobs of magma that harden in the air
29. solid rock blasted out of a volcano
30. glass-like slivers from walls of exploding gas
bubbles
a. volcanic blocks
b. volcanic bombs
c. lapilli
d. volcanic ash
31. pebblelike bits of magma that cool in the air
32. When large amounts of hot ash, dust, and gases are ejected from a volcano,
the result is a dangerous type of flow called a(n)
.
33. Pyroclastic materials can race downhill at speeds over____________________.
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Holt Science and Technology
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Volcanoes