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Sea-Floor Spreading
Write the letter of the correct answer on the line at the left.
1.
Which features form the longest
mountain ranges on Earth?
A the mid-ocean ridges
B the deep-ocean trenches
C the Rockies
D the Andes
3.
A
B
C
D
Where does subduction occur?
along the middle of some ocean floors
down the middle of mountain ranges
on continents
at deep-ocean trenches
2.
Which process adds more crust to
the ocean floor?
A suction
B sea-floor spreading
C subduction
D magnetic stripe
4.
Which process or processes change
the size and shape of the oceans?
A subduction only
B sea-floor spreading only
C both subduction and sea-floor spreading
D both drilling for samples and subduction
If the statement is true, write true. If the statement is false, change the underlined word
or words to make the statement true.
5.
Sonar is a device that scientists use to map the ocean floor.
6.
A deep-ocean trench is an underwater mountain.
7.
Molten material erupts inside the central valley of mid-ocean
ridges.
8.
9.
10.
The farther from a mid-ocean ridge a rock sample is taken,
the younger the rock is.
Sea-floor spreading occurs at mid-ocean ridges.
The pattern of magnetic stripes in rocks on either side of a
mid-ocean ridge is the same.
85G