Download Vocabulary Review Summary of Key Ideas

Vocabulary Review
Summary of Key Ideas
23.1 To determine the shape and composition of the
ocean floor, scientists use techniques such as echo
sounding, sediment sampling, and satellite
observation.
23.2 A continental margin (the underwater edge of
a continent) can be active or passive, depending
where it lies in relation to a subduction zone or
transform fault.
23.3 The ocean basin’s topography varies
widely and includes features such as abyssal plains
and hills, deep-ocean trenches, and mid-ocean
ridges.
23.4 Ocean-floor sediments vary in
Write the term from the key vocabulary list that best
completes the sentence.
1. A precision depth recorder uses the technique of
?
to determine ocean depth.
2. The continental shelf extends from the shoreline
?
to the
, where water depth begins to
increase rapidly.
3. The margin where an oceanic plate is subducting
?
under a continental plate is called
.
4. Composed of ocean-floor sediments,
?
a(n)
stretches out from the continental
rise and is the flattest of all Earth’s surfaces.
5. Oozes are the decomposed remains of marine
?
protists and animals, also called
.
Concept Review
6. In what ways is core sampling useful to our
understanding of Earth and its oceans?
composition. Scientists classify each sediment
based on where it originated.
7. Is the continental rise part of the ocean basin, or
part of a continent? What about the continental
shelf? the continental slope?
KEY VOCABULARY
8. Most of the sediments that compose the abyssal
plain originated on continents. Describe how the
sedimentary materials could have moved from
land to the deep-ocean floor.
abyssal hill (p. 517)
fracture zone (p. 520)
abyssal plain (p. 517)
guyot (p. 520)
active continental
hydrogenous
margin (p. 515)
biogenous sediments
sediments (p. 525)
island arc (p. 518)
9. Explain two possible origins of large submarine
canyons.
continental margin (p. 514) passive continental
10. Why are deep-ocean trenches such common
sites for earthquakes and volcanic eruptions?
continental rise (p. 514)
11. How do mid-ocean ridges form?
(p. 524)
mid-ocean ridge (p. 519)
margin (p. 515)
continental shelf (p. 514)
seamount (p. 520)
continental slope (p. 514)
submarine canyon (p. 515)
coral atoll (p. 521)
terrigenous sediments
core sampling (p. 511)
deep-sea trench (p. 518)
(p. 523)
turbidity current (p. 516)
echo sounding (p. 510)
12. How can a coral atoll be attached to the ocean
floor when corals cannot live (or, therefore, form
reefs) in the deep ocean?
13. What is the difference between an ooze and
other sediments?
14. Are you more likely to find a deep-ocean trench
along an active continental margin or along a
passive continental margin? Sketch and label a
diagram to explain your answer.
528
Unit 6 Earth’s Oceans