Skills Worksheet
13.2 - Directed Reading A
Section: The Ocean Floor
STUDYING THE OCEAN FLOOR
_____ 1. What does sonar stand for?
a. sound and radar
b. sound navigation and radio
c. sub-ocean navigation and ranging
d. sound navigation and ranging
_____ 2. Sonar technology is based on the echo-ranging behavior of
a.
b.
c.
d.
sea lions.
bats.
moths.
seals.
_____ 3. What does Seasat measure?
a.
b.
c.
d.
changes in the ocean’s height
changes in the ocean’s landforms
the direction and speed of ocean currents
the velocity of waves hitting the shoreline
_____ 4. What does Geosat measure?
a.
b.
c.
d.
changes in the height of ocean surface
changes in the ocean’s landforms
the direction and speed of ocean currents
the velocity of waves hitting the shoreline
_____ 5. Using satellites to make maps of the ocean floor is better than using
ship-based sonar because
a. satellites are farther away from the ocean.
b. satellites cover more territory.
c. ships are always getting lost.
d. satellites are less expensive.
6. How fast does sound travel in water?
____________________________________________________________________
____________________________________________________________________
7. How do scientists use sound to figure out the depth of the ocean?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
5
Exploring the Oceans
Directed Reading A continued
REVEALING THE OCEAN FLOOR
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 8. begins at the shoreline
a. continental rise
_____ 9. slopes from the continental shelf to the
ocean floor
b. abyssal plain
_____ 10. forms the base of continental slope
d. continental slope
c. continental shelf
_____ 11. is covered by mud
12. The two major regions of land under the water are the continental margin and
the ______________________ basin.
13. If the ocean were a giant swimming pool, the
______________________would be the shallow end.
14. Mountain chains formed by magma coming through rift zones are
called______________________
15. Mountains on the ocean floor that can turn into volcanic islands are
called______________________
16. When one oceanic plate is forced underneath another plate,
a(n)______________________forms.
17. As mid-ocean ridges build up, a(n) ______________________forms between
them in the rift zone.
18. Where do mid-ocean ridges and ocean trenches form?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
6
Exploring the Oceans
Directed Reading A continued
EXPLORING THE OCEAN FLOOR WITH UNDERWATER VESSELS
19. What is Alvin?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
20. What kinds of missions has Alvin been on?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
21. Why did the developers of Deep Flight give it that name?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
22. Why are scientists beginning to use more robotic vessels to study the ocean?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
23. How does the robot team of JASON II and of Medea work?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
_______________________________________________________________
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Science and Technology
7
Exploring the Oceans