Oceanography

Which of the following probably had the least effect on the formation of the Earth’s oceans?

• The condensation of water vapor as the Earth’s crust cooled.

• Frequent thunderstorms occurring for thousands of years.

• Impacts of meteorites with the Earth’s surface.

• Water removed from hydrated compounds found in the Earth’s crust.

Areas were the plates on the seafloor are spreading apart form underwater mountain ranges called

• ridges.

• trenches.

• seamounts.

• guyots.

When plates collide, one plate plunges below the other plate in a process called

• adduction.

• succession.

• subduction.

• conduction.

The deepest point ever recorded on the ocean floor is found in the

• Mid-Atlantic Ridge.

• Marianas Trench.

• Aleutian Trench.

• Kuril Trench.

Because of the movement of oceanic plates, the Atlantic Ocean is getting ______ and the Pacific Ocean is getting ______.

• wider, narrower

• narrower, wider

• wider, wider

• narrower, narrower

Which of the following is NOT a reason why SONAR is used to map the ocean floor?

• The lack of light on the ocean floor makes it difficult to create a map any other way.

• The sounds waves produced by SONAR equipment do not disrupt local animal life.

• SONAR is much faster and cheaper than sending down an underwater vehicle.

• Some of the regions that are to be mapped are much too deep to be explored.

A research vessel equipped with SONAR has been sent out to map the ocean floor. If it takes 1.5 seconds for a sound wave to bounce off the ocean bottom and return to the ship, how deep is this area of the ocean?

• 2181 meters

• 1938.7 meters

• 1090.5 meters

• 727 meters

Which of the following best explains why polar water is colder than equatorial water?

• The poles receive a lower angle of insolation.

• Global currents bring colder water to the poles.

• Tidal movement leaves colder water at the poles.

• Water at the poles has a higher specific heat than water at the equator.

Which of the features above is most likely a guyot?

• 8

• 4

• 10

• 5

Which of the features above is most likely a trench?

• 2

• 9

• 8

• 6