2. The water that creates the oceans was

brought to Earth in the ice of comets.
brought out of the Earth by volcanic activity.
pushed to Earth in the form of water vapor by the solar wind.
formed largely by chemical reactions that occurred on the early Earth.
A and B

3. Which is the main rock type that composes the following?

continents - granitic rock; ocean basin crust - sedimentary rock
continents - granitic rock; oceanic basin crust - basaltic rock
continents - andesitic rock; ocean basin crust - sedimentary rock
continents - sedimentary rock; ocean basin crust - basaltic rock

4. The correct order of the first three sea floor regions from the continents seaward would be:

continental shelf, continental rise, continental slope
continental shelf, continental rise, abyssal plain
continental shelf, continental slope, submarine canyons
continental shelf, continental slope, continental rise
continental shelf, continental slope, deep sea trench

5. Choose the true statement.

The continental shelf is steep, 2km-70 km wide and extends to a depth of about a kilometer.
The continental shelf is rather flat, an average of 2km-70 km wide and extends to a depth of about 200 meters.
The continental shelf is rather flat, 2km-170 km wide and extends to a depth of about 300 meters.
The continental shelf is steep, 2km-170 km wide and extends to a depth of about 200 meters.
All continental shelves increase the size of a continent by several hundred miles.

6. The continental rise is a(an)

shallow slope of deposited materials, from the continents, that becomes thinner and finer the farther out it goes.
shallow slope of solid rock forming the base of the continent.
edge of the continent that is created by a steep slope of solid rock.
edge of the continent that is created by an abrupt cliff.

7. Choose the correct statement concerning submarine canyons.

They are only found on the Atlantic side of our continent.
They are only formed on continental shelves.
They tend to be "V" shaped valleys formed only by faults.
It is still somewhat of a mystery as to exactly how they are carved and why they are so deep.
A and D

8. The abyssal plain is covered with

sediment and submarine lava flows.
many thin layers of sediment.
organic sediment only.
sediment plus many large seamounts sticking up.

9. Pelagic sediment

consists of tiny solid bits of plankton and clay that fall to the deep ocean floor.
is found mainly on the continental shelf.
is called snow because it forms drift-like deposits against the continental shelf.
is called snow because it only covers the tops of seamounts.

10. Oceanic ridges

contain some of the oldest rock found in the oceans.
are considered small and minor compared to other landforms on the ocean floor.
have been built up entirely from layers of pelagic sediment and lava flows.
create a large interconnected system of mountains that wind around the Earth.

11. The oldest rock on the ocean floor is found

farthest from the oceanic ridges and nearer continents.
farthest from the oceanic ridges and far from the edges of continents.
closer to the oceanic ridges and far from the edges of continents.
closer to the ocean ridges and fairly near the edges of continents.

12. The process of sea floor spreading includes material

moving away from an oceanic ridge, cooling and sinking by a process known as subduction.
piling up on a ridge and warming as it slides down a trench.
moving away from an oceanic ridge then piling up and subducting.
piling up on a ridge, warming and then subducting.

13. A correct descriptive sequence that describes the sea floor rock as one moves away from a mid-oceanic outward is

cooler, denser, older, trenches.
cooler, denser, younger, trenches.
cooler, denser, warmer, younger, trenches.
warmer, denser, younger, trenches.

14. Potentially important economic deposits that have formed in the ocean basins are:

manganese nodules on the ridges; metals like copper, zinc, iron and gold on the deeper sea floor.
manganese nodules along with other metals like copper, zinc, iron and gold on the ridges.
manganese nodules on the deeper sea floor and metals like copper, zinc, iron and gold on the ridges.
oil and gas on the continental shelves and manganese nodules on the ridges

15. Larger, active, hydrothermal vents are found

near the ridge tops depositing limestone-like materials.
near the centers of ridges depositing heavy metals like copper and zinc.
on the lower flanks of the ridges depositing heavy metals like copper and zinc.
on the lower flanks of the ridges depositing limestone-like materials.

Lesson "Birth of a Theory"

16. The theory of plate tectonics proposes that

large slabs of the outer Earth slide on a partially liquid core.
mountain building, volcanoes and earthquakes are all part of a unified system.
mountain building and volcanoes can be traced directly to processes occurring in the inner core.
large slabs of the outer Earth slide on a liquid mantle.

17. Alfred Wegener used all but one of the following to support his theory of Continental Drift. Which one did he notuse?

the matching of similar plant and animal fossils from continent to continent
the matching of similar rock types and geologic formations from continent to continent
the matching of the "fit" or shapes of continents across ocean basins
magnetic studies

18. The critical difference between modern plate tectonics and Wegener's continental drift is that in the modern theory

the continents "plow" through the ocean basins.
both the continents and the ocean floor are moving.
continents descend to form new ocean floor.
earthquakes occur in areas of plate movement.

19. All the following ideas concerning guyots (gee-ohz) are true except:

they are flatted topped seamounts.
they are highly eroded volcanoes that have subsided to form mid-oceanic ridges.
the deepest guyots are farthest from the oceanic ridges.
their tops are eroded by ocean waves and then they are carried to deeper water as the crust beneath subsides.

20. According to the idea of sea floor spreading, if the floors of the ocean basins are growing by spreading laterally, then

paleomagnetism must be shrinking the plates in other areas.
magnetism must be forming trenches.
oceanic crust must sink back into the mantle at trenches.
oceanic crust must sink back into the mantle in the centers of ridges.

21. The alternating magnetic patterns detected on the ocean floor (choose the incorrect choice)

are found in stripes parallel to the oceanic ridges.
are caused by reversals in the polarity of the Earth's magnetic field.
are a part of a study that geologists call paleomagnetism.
form zones of extremely strong magnetism found only near the oceanic ridges.

22. The faulting and offsetting that occurs across (at right angles to) mid-oceanic ridges is called

normal faulting.
tranform faulting.
reverse faulting.
hinge faulting.

23. Drill core samples from the ship "Glomer Challenger" indicated that the rock was

older away from the ridge which helped verify the normal faulting.
older away from the ridge which helped verify the reverse faulting.
more magnetized away from the ridge which helped verify the reverse faulting.
less magnetized away from the ridge which helped verify the reverse faulting.
older away from the ridge which helped verify the idea of sea floor spreading.

24. One of the strengths of the theory of plate tectonics is that it

unifies many ideas that are seemingly unrelated.
easily explains why plates move.
explains the position of the north magnetic pole.
explains the distribution of climates around the world.

25. Perhaps one of the biggest questions yet to be answered by the theory of plate tectonics is:

why does convection occur in the mantle?
why does convection occur in the crust?
why do some plates sink, others rise?
does convection primarily push or pull plates?

Prepared by: Mike Mitchell

Be sure to review your quizzes before taking the test.