Which is the main rock type that composes the following?
A. continents-granitic rock; ocean basin crust-sedimentary rock
B. continents-granitic rock; ocean basin crust-basaltic rock
C. continents-andesitic rock; ocean basin crust-sedimentary rock
D. continents-sedimentary rock; ocean basin crust-basaltic rock
ANSWER: 

We know about magnetic reversals because
A. mariners have noticed changes in the position of the magnetic poles for centuries.
B. of the record left in magnetic minerals found in layers of lava flows.
C. the force of Earth's magnetic field is now steadily diminishing.
D. measurements from sediments at Mono lake, California, indicate such a reversal about 28,000 years ago.
ANSWER: 

During periods of maximum glaciation
A. the continental shelves were exposed as dry land.
B. the continental rises were dry land.
C. sea level rose and inundated continental shelves.
D. shells of deep water organisms were deposited on the shelves.
ANSWER: 

The correct order of the first three sea floor regions from the continents seaward along passive continental margins would be the
A. continental shelf, continental rise and continental slope.
B. continental shelf, continental rise and abyssal plain.
C. continental shelf, continental slope and submarine canyons.
D. continental shelf, continental slope and continental rise.
E. continental shelf, continental slope and deep sea trench.
ANSWER: 

The most important source of the water in the oceans is probably largely from
A. rivers and streams.
B. degassing of the Earth's interior by volcanic activity.
C. subterranean water pockets.
D. photosynthesis.
ANSWER: 

The continental shelf may be described as a
A. flat surface of sediments overlying a granite basement.
B. steep slope leading to the deep sea floor.
C. flat surface made up of andesitic lava flows.
D. flat surface with a thin veneer of sediments overlying pillow lavas.
ANSWER: 

Which of the following is not considered one of the main difficulties in exploring the deep ocean floor?
A. The near freezing temperatures.
B. darkness
C. The crushing pressures of the water.
D. The strong currents.
ANSWER: 

Which of the following give the most convincing evidence of sea floor spreading?
A. The andesitic volcanism of the island arcs.
B. The thick sediments of the shelves, slope, and rises.
C. The rift valleys of mid-oceanic mountains.
D. The active continental margins of the Atlantic Basin.
ANSWER: 

The largest, active hydrothermal vents are found
A. near the mid-oceanic ridge tops where they deposit limestone-like materials.
B. near the mid-oceanic ridge tops where they deposit heavy metals like copper and zinc.
C. on the lower flanks of the mid-oceanic ridges where they deposit heavy metals like copper and zinc.
D. on the lower flanks of the mid-oceanic ridges where they deposit limestone-like materials.
ANSWER: 

Choose the correct statement concerning submarine canyons.
A. They are only found on the Atlantic side of our continent.
B. They are only formed on continental shelves.
C. They tend to be "V" shaped valleys formed only by faults.
D. It is still a mystery as to exactly how all of them are carved and why they are so deep.
E. A and D
ANSWER: 

The correct descriptive sequence that describes the sea floor as one moves away from a mid-oceanic ridge outward is :
A. cooler, denser, older, trenches
B. cooler, denser, younger, trenches
C. cooler, denser, warmer, younger, trenches
D. warmer, denser, older, trenches
ANSWER: 

The ocean basins lie at lower elevations than the continents because
A. basalt is denser than granite.
B. the basins are depressed by the weight of the water.
C. the sea floor sediments are thicker and heavier than the continental sediments.
D. andesite is denser than basalt.
ANSWER: 

Potentially important economic deposits that have formed in the ocean basins are:
A. manganese nodules on the mid-oceanic ridges; metals like copper, zinc, iron and gold on the deeper sea floor.
B. manganese nodules along with other metals like copper, zinc, iron and gold on the mid-oceanic ridges.
C. manganese nodules on the deeper sea floor and metals like copper, zinc, iron and gold on the mid-oceanic ridges.
D. oil and gas on the continental shelves and manganese nodules on the mid-oceanic ridges.
ANSWER: 

According to oceanographic studies,
A. the sea floor is approximately the same age everywhere in the Pacific.
B. only in the Atlantic is new sea floor formed at the deep sea trenches.
C. old sea floor in all oceans is subducted in the rift valleys.
D. new sea floor is formed at the rift valleys in the mid-oceanic ridges.
ANSWER: 

When geologists say the sea floor is like a "tape recorder," they mean it contains a record of all of the following except
A. reversals of the Earth's magnetic polarity.
B. the rate of spreading of the sea floor.
C. the rate of expansion of the Earth.
D. the time of magnetic reversals.
ANSWER: 

The oldest rock on the ocean floor is found 
A. farthest from the oceanic ridges and nearer continents.
B. farthest from the oceanic ridges and far from the edges of continents.
C. closer to the oceanic ridges and far from the edges of continents
D. closer to the oceanic ridges and fairly near the edges of continents.
ANSWER: 

The alternating magnetic patterns detected on the ocean floor
A. are found in stripes perpendicular to the oceanic ridges.
B. are caused by reversals in the Earth's magnetic field.
C. are a part of a study that geologists call paleoclimatology.
D. form zones of extremely strong magnetism found only near the oceanic ridges.
ANSWER: 

Drill core samples from the ship "Glomer Challenger" indicated that sea floor rock was
A. older as one moved away from mid-oceanic ridges which helped verify the normal faulting.
B. older as one moved away from mid-oceanic ridges which helped verify the reversed faulting.
C. more magnetized away from mid-oceanic ridges which helped verify the reversed faulting.
D. less magnetized away from mid-oceanic ridges which helped verify the reversed faulting.
E. older as one moved away from mid-oceanic ridges which helped verify the idea of sea floor spreading.
ANSWER: 

What records and preserves magnetic patterns on the sea floor?
A. Iron-rich minerals in the sea floor rock.
B. The sea floor's nearness to the Earth's iron-nickel core.
C. Periodic reversals in the Earth's magnetic field.
D. A periodic increase in sunspot activity.
ANSWER: 

To which of the following does the worldwide average rate of plate growth at a spreading center (6 centimeters per year) most closely correspond?
A. The rate at which a plate thickens as it cools.
B. The rate of plate consumption at subduction zones.
C. Ten times the growth rate of a human fingernail.
D. The rate of uplift of an active continental mountain range.
ANSWER: 

The critical difference between modern plate tectonics and Wegener's continental drift is that in the modern theory
A. the continents "plow" through the ocean basins.
B. both continents and ocean floor are moving.
C. continents descend to form new ocean floor.
D. earthquakes occur in areas of plate movement. 
ANSWER: 

Which of the following ideas concerning guyots is not true?
A. They are flat topped seamounts.
B. They are highly eroded volcanoes that have subsided to form mid-oceanic ridges.
C. The deepest guyots are farthest from the mid-oceanic ridges.
D. Their tops are eroded by ocean waves and then they are carried to deeper water as the crust beneath subsides.
ANSWER: 

One of the biggest questions yet to be answered by the theory of plate tectonics is:
A. Why does convection occur in the mantle?
B. Why does convection occur in the crust?
C. Why do some plates sink, others rise?
D. Does convection primarily push or pull plates?
ANSWER: 

If the age of the sea floor rock and the distance it has moved from its mid-oceanic ridge are known, which of the following can be most easily calculated?
A. The rate of plate movement.
B. The magnetic polarity of the plate at that point.
C. The length of time before subduction.
D. The thickness of the sea-floor crust.
ANSWER: 

The result of an oceanic plate converging with an oceanic plate is a
A. large volcanic mountain chain like an oceanic ridge in structure and composition.
B. collision zone that can create mountains.
C. volcanic string of islands.
D. volcanic string of islands composed of a rhyolite type rock with some andesite.
ANSWER: 

A towel lies spread out on the water's surface in a swimming pool. One end becomes water-soaked and heavier. Which phenomenon is best illustrated by the water-soaked end of the towel pulling the rest of the towel underwater?
A. divergence
B. transform faulting
C. subduction
D. convection
ANSWER: 

The result of an oceanic plate converging with a continental plate is a
A. volcanic mountain chain like the Cascade Range in Oregon and Washington.
B. collision zone that can create mountains.
C. volcanic mountain chain much like an oceanic ridge.
D. volcanic mountain chain composed of basaltic rock only.
ANSWER: 

Which statement best describes the asthenosphere?
A. A rigid layer in the lower crust.
B. A plastic layer in the lower crust.
C. A plastic layer of upper mantle material.
D. A rigid layer in the upper mantle.
ANSWER: 

Oceanic crust always subducts beneath continental crust because it
A. is heavier and hotter.
B. is heavier and thinner.
C. is denser and hotter.
D. sinks to form trenches.
ANSWER: 

Choose the correct statement concerning the strength of earthquakes.
A. Earthquakes tend to be more powerful at convergent boundaries than at divergent boundaries.
B. Earthquakes tend to be more powerful at convergent boundaries than in subduction zones.
C. Earthquakes tend to be more powerful at divergent boundaries than at transform boundaries.
D. Earthquakes tend to be more powerful at divergent boundaries than at convergent boundaries.
ANSWER: 

Which layer of the Earth has properties that are thought to be partially molten and act as a lubricant for plate movement?
A. lithosphere
B. asthenosphere
C. middle mantle
D. lower mantle
ANSWER: 

The origin of the Hawaiian Island chain is best explained as 
A. eruptions proceeding southward along a major fault.
B. islands formed on a sea floor divergent boundary.
C. islands formed on an island arc-trench system.
D. islands formed on a plate moving over a mantle plume.
ANSWER: 

Convection may move plates by
A. pushing them apart only.
B. pulling them apart only.
C. pushing them apart or pulling them apart.
D. pulling them upward as the rock under them convects sideways only.
ANSWER: 

The Mariana trench, the deepest place on Earth, has its origins as a
A. subduction zone near an island arc.
B. rift valley in the crest of the East Pacific Rise.
C. graben on an opening sea floor.
D. backarc spreading center. 
ANSWER: 

All of the Earth's ocean floor originated
A. in the subduction zones.
B. in the rifts of the mid-oceanic ridges.
C. as backarc spreading.
D. from continental collision.
ANSWER: 

The San Andreas Fault represents the break between the Pacific and 
A. Northwest American Plates.
B. North American Plates.
C. American Plates.
D. Great Western Pacific Plates.
ANSWER: 

Of the following, which is not considered part of a young or older rifting sea?
A. Red Sea
B. Mediterranean Sea
C. Gulf of Mexico
D. Atlantic Ocean
ANSWER: 

Subduction zones are important to the theory of plate tectonics because they are regions where
A. new sea floor is being formed.
B. plates diverge or pull-apart.
C. plates converge and older sea floor material is being "consumed".
D. continental masses are coming together.
ANSWER: 

One major area of uncertainty in the theory of plate tectonics is the
A. exact cause of plate motion.
B. origin of the sea floor.
C. exact origin of island arcs.
D. cause of earthquakes along the San Andreas fault.
ANSWER: 

Mount Everest, the tallest mountain on Earth, apparently grew as the result of
A. a continent-continent collision.
B. an island arc formation.
C. basaltic volcanic eruptions.
D. its location on a rifting continental margin.
ANSWER: 

The last great mountain building episode of the Appalachian Mountains (eastern coast of the United States) took place
A. during the break-up of Pangaea.
B. when Africa pushed against and became attached to North America.
C. before the accumulation of thick sediments in that area.
D. when the Atlantic Ocean basin rifted apart.
ANSWER: 

Most geologists believe that
A. the original plates were small but thicker.
B. originally the lithosphere was thinner and convection was faster.
C. the original continents were larger and thinner.
D. the original plates were more rigid.
ANSWER: 

Accreted terrane are
A. recognized by their distinct composition and boundaries that are marked by faults or belts of ocean sediment.
B. recognized by their distinctive shapes and boundaries marked by faults.
C. recognized by the age of their rock and boundaries marked by ocean sediment.
D. found only in the northwest and Alaska.
ANSWER: 

As mountains erode,
A. they become lower very quickly.
B. their softer roots become exposed.
C. they are pushed up by the process of isostasy.
D. their compositions change because the softer root material intrudes upward.
ANSWER: 

The oldest portions of continents usually involve
A. accreted terranes.
B. active volcanic mountain ranges.
C. an active collision boundary.
D. highly eroded mountain ranges.
ANSWER: 

What conditions tend to make rocks bend or flow? Choose the most complete answer.
A. high pressures and temperatures
B. high pressures and soft rock
C. high temperatures and slow stresses
D. high temperatures, pressures and slow stresses
ANSWER: 

If you were doing field work near a plate boundary that you believed had undergone collision, which of the following structures would you be least likely to find?
A. anticlines
B. reverse faults
C. rift valleys or grabens
D. thrust faults
ANSWER: 

Examples of dip-slip faulting would be given by
A. reverse, normal and thrust faults
B. reverse, normal and right lateral faults
C. reverse, normal and left lateral faults
D. normal, thrust faults and oblique faults.
ANSWER: 

Many people in Los Angeles know they are slowly creeping northward along the San Andreas fault. To the geologist, this means the San Andreas Fault is a
A. right lateral strike-slip fault.
B. normal fault.
C. reverse fault.
D. left-lateral fault.
ANSWER: 

Two common types of seismic waves generated by earthquakes are
A. "P" waves that arrive first and "S" waves that arrive second.
B. "P" waves that are pressure waves and "S" waves that are slower.
C. "P" waves that are pressure waves and "S" waves that are shear waves.
D. all the above.
ANSWER: 

Basic forms of folding are
A. anticlines that are upfolded and synclines that are downfolded.
B. anticlines that are downfolded and synclines that are upfolded.
C. anticlines that are downfolded and monoclines that are upfolded .
D. synclines that are upfolded and monoclines that are downfolded.
ANSWER: 

The main classes of structures formed by derformation are
A. basins, faults and domes.
B. domes, fractures/faults and folds.
C. unconformities, fractures/faults and basins.
D. fractures/faults, folds and unconformities.
ANSWER: 

According to the video, what distinquishes an active fault from an inactive fault?
A. A record of movement during historic time.
B. Evidence of the fault at the surface.
C. The presence of springs, hot springs or geysers along the fault.
D. The presence of folds nearby.
ANSWER: 

Fracture tends to occur
A. in the shallow crust where rocks are softer and warmer.
B. where rocks are softer and cooler.
C. in areas of the shallow crust where stresses work rapidly and rocks are cooler and brittle.
D. mainly where basalt occurs.
ANSWER: 

Faults are named according to their motion along the plane of rupture. Correct examples are:
A. dip-slip = vertical motion; transform = vertical motion
B. dip-slip = vertical motion; strike-slip = horizontal motion
C. dip-slip = horizontal motion; strike-slip = vertical motion
D. dip-slip = horizontal motion; strike-slip = horizontal motion
ANSWER: 

Maps showing the global locations of earthquakes reveal that
A. earthquakes are evenly distributed around the world.
B. most earthquakes follow the borders of the Atlantic Ocean
C. most earthquakes occur in the interior of continents.
D. most earthquakes surround the Pacific basin.
ANSWER: 

Few earthquakes occur below a depth of about 700 kilometers (420 miles) into the Earth because
A. plate movements do not extend that deep.
B. rocks are hard and compressed below that depth and do not break.
C. faults large enough to cause earthquakes are surface phenomena.
D. the rocks are hotter and flow plastically below that depth.
ANSWER: 

The point within the Earth where seismic waves from an earthquake originate is called the
A. epicenter.
B. seismocenter.
C. Mercalli point.
D. focus.
ANSWER: 

The seismic waves that are transmitted by solids, liquids, and gases are also
A. the first to arrive at a seismograph.
B. fastest moving and most damaging as they shake the ground from side to side.
C. the slowest of the waves that have a simple up and down motion.
D. the compressional and extensional waves with the highest amplitude.
ANSWER: 

The difference in time between the arrival of the P and S waves
A. is a function of the intensity of the waves.
B. enables seismologists to calculate the strength of an earthquake.
C. is a function of the distance to the epicenter.
D. does not vary much from earthquake to earthquake.
ANSWER: 

Even though theoretically the Richter Scale runs from -2 to infinity (according to the video), the highest magnitudes currently thought possible are about
A. 7, because rock can only allow a limited amount of stress to accumulate.
B. 9, because rock can only allow a limited amount of stress to accumulate.
C. 10, because plates move too slowly to generate any higher levels of stress.
D. 10.5, because plates move intermittently allowing stress to be dissipated before they accumulate to greater levels.
ANSWER: 

An earthquake with a magnitude of 6 releases about ? more energy than an earthquake of magnitude of 4.
A. 10 times
B. 30 times
C. 100 times
D. 1,000 times
ANSWER: 

Several techniques and monitoring devices are used along fault lines to detect motion and the build up of strain. Which of the following is not properly associated?
A. creep meters and alignment arrays - for the detection of surface movement
B. creep meters and geodometers - for the detection of surface movement
C. changes in groundwater levels - indicate very wide spread surface movement
D. geodometers - for the detection of wide spread surface movement
ANSWER: 

By using differences in the rate at which seismic waves travel to various recording stations, and graphing circles from at least three stations on a map, scientists can determine an earthquake's
A. epicenter.
B. depth of focus.
C. intensity.
D. magnitude.
ANSWER: 

On a magnitude scale, like the Richter Scale, the amount of shaking or amplitude of an earthquake changes ? as the magnitude increases by one.
A. slightly
B. by a factor of 10
C. by a geometric progression
D. by a factor of 31.5
ANSWER: 
