Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Directed Reading 23-2
Section: Features of the Ocean Floor
_____ 2. The shallow ocean floor between the shoreline and the deep-ocean
basin is called the
a. continental margin.
b. shallow-ocean basin.
c. continental crust.
d. oceanic crust.
_____ 4. The part of the ocean floor under deep water beyond the continental
margin is called the
a. continental margin.
b. deep-ocean basin.
c. continental crust.
d. oceanic crust.
CONTINENTAL MARGINS
_____ 6. The line that divides the continental crust from the oceanic crust is
a. distinct.
b. on the surface.
c. under thick sediments.
d. at the shoreline.
_____ 7. The part of the continent covered by water is called the
a. shoreline.
b. continental margin.
c. continental shelf.
d. deep-ocean basin.
_____ 9. The average depth of the water covering a continental shelf is about
a. 6 m.
b. 60 m.
c. 160 m.
d. 600 m.
_____ 10. The continental shelf is part of the
a. continental margin.
b. deep-ocean basin.
c. ocean surface.
d. oceanic crust.
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The Ocean Basins
Name ______________________________ Class ___________________ Date __________________
Directed Reading continued
_____ 13. The steep slope at the seaward edge of a continental shelf is called the
a. continental rise.
b. continental slope.
c. oceanic slope.
d. oceanic rise.
16. Deep V-shaped valleys in the continental shelf and continental slope are called
______________________.
17. What is one place submarine canyons are often found?
_______________________________________________________________
_______________________________________________________________
20. The wedge of sediment at the base of the continental slope is called a(n)
______________________.
DEEP-OCEAN BASINS
21. What are four features of deep-ocean basins?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
23. What is the name of the deepest place in Earth’s crust?
_______________________________________________________________
25. About how deep is the deepest place in Earth’s crust?
_______________________________________________________________
27. How do trenches form in deep-ocean basins?
_______________________________________________________________
_______________________________________________________________
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The Ocean Basins
Name ______________________________ Class ___________________ Date __________________
Directed Reading continued
28. List three things that occur or form near trenches.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
29. In deep-ocean basins, what are abyssal plains?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
31. The flattest regions on Earth are ____________________________________.
36. Compare the sediment cover on abyssal plains that are bordered by trenches
with the sediment cover on abyssal plains not bordered by trenches.
_______________________________________________________________
_______________________________________________________________
37. The most prominent features of ocean basins are _______________________.
38. Mid-ocean ridges form underwater __________________________________.
39. What is one place where a mid-ocean ridge rises above sea level?
_______________________________________________________________
41. What runs along the center of a mid-ocean ridge?
_______________________________________________________________
42. How does magma reach the sea floor?
_______________________________________________________________
47. Faults create rough areas called ______________________, which run
perpendicularly across mid-ocean ridges.
48. Where do seamounts form?
_______________________________________________________________
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Holt McDougal Earth Science
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The Ocean Basins
Name ______________________________ Class ___________________ Date __________________
Directed Reading continued
In the space provided, write the letter of the definition that best matches the term
or phrase.
_____ 49. guyot
_____ 50. hot spot
_____ 51. seamount
_____ 52. atoll
_____ 53. oceanic island
a. an area of increased volcanic activity
b. submerged seamount with a flat top
c. a seamount that rises above the ocean surface
d. an oceanic island formed from coral reefs that
surround a sinking and eroding seamount
e. submerged volcanic mountain taller than 1 km
Original content Copyright © Holt McDougal. All rights reserved. Additions and changes to the original content are the responsibility of the instructor.
Holt McDougal Earth Science
17
The Ocean Basins