The Sea Floor

Earthquakes

  1. If density increases, the velocity of a P wave should (according to the equation):

    1. stay the same
    2. increase
    3. decrease

  2. If a P wave were to go from a rock to a liquid - what would happen to its velocity?

    1. stay the same
    2. increase
    3. decrease
    4. go to zero

  3. If an S wave were to go from a rock to a liquid - what would happen to its velocity (use the equation)

    1. stay the same
    2. increase
    3. decrease
    4. go to zero

  4. Think of a boundary where a P and S wave would go from solid to liquid (100%) or liquid to solid.

    1. outer core - mantle
    2. lithosphere - asthenosphere
    3. inner core - outer core
    4. 1 and 4 are both correct

  5. Body waves consist of the:

    1. P waves only
    2. S waves only
    3. P and S waves
    4. Surface waves

  6. With increasing travel time the difference in arrival times between the P and the S waves:

    1. increases
    2. decreases
    3. stays constant
    4. none of the above

  7. Earthquake has a RIchter magnitude of 7 as compared with earthquake B's 5. The difference in wave amplitude between B and A is:

    1. 100X
    2. 2X
    3. .01X
    4. 12X

  8. In general, the most destructive earthquake waves are the:

    1. P
    2. S
    3. Surface
    4. horizontal

  9. Where is the focus with respect to the epicenter:

    1. directly above
    2. directly below
    3. on the other side of the Earth
    4. none of the above

  10. Which waves are recorded by a seismograph located in the shadow zone of an earthquake?

    1. P
    2. S
    3. Surface
    4. all are recorded

Interior of the Earth

  1. Which one of the following term associations most accurately describes oceanic crust?

    1. basaltic; density of 3.0 g/cm3
    2. granitic; density of 3.0 g/cm3
    3. quartz arenites of 2.6 g/cm3
    4. granitic, density of 2.6 g/cc

  2. The Moho separates:

    1. the outer core from the inner core
    2. the asthenosphere from the mesosphere
    3. the lithosphere from the asthenosphere
    4. the crust from the mantle

  3. Which one of the following term associations is FALSE?

    1. asthenosphere --- plastic
    2. lithosphere --- rigid solid
    3. outer core --- rigid solid
    4. oceanic crust --- rigid solid
    5. continental crust --- rigid solid

  4. To induce a positive Bouguer anomaly, a rock unit should have the following property:

    1. transmit only P waves
    2. be denser than average
    3. transmit only L waves
    4. demonstrate magnetic inclination
    5. lie within the seismic shadow zone

  5. The lithosphere represents:

    1. crust and uppermost, rigid mantle
    2. uppermost rigid mantle, only
    3. asthenosphere and the mesosphere
    4. outer core and the inner core

  6. A magnetic material _________ its magnetic character at its Curie temperature:

    1. gains (on cooling below)
    2. looses (on heating above)
    3. both are correct

Plate Tectonics

  1. Transform faults:

    1. often offset spreading centers
    2. can cut across continents
    3. involve horizontal movement
    4. all of the above

  2. Stretching streses, basaltic lavas, and shallow earthquakes are associated with:

    1. subduction zones
    2. continent/continent convergence
    3. spreading centers
    4. transform fault boundaries

  3. Compressive streses, granitic magmas, and intermediate depth earthquakes are associated with:

    1. subduction zones
    2. continent/continent convergence
    3. spreading centers
    4. transform fault boundaries

  4. Shearing stresses and shallow earthquakes are associated with:

    1. subduction zones
    2. continent/continent convergence
    3. spreading centers
    4. transform fault boundaries

  5. If the Atlantic Ocean is widening at a rate of 3 cm per year how far (in kilometers) will it spread in a million years?

    1. 300 km
    2. 30 km
    3. 30 miles
    4. 3 km

  6. In 50 million years?

    1. 1500 km
    2. 150 km
    3. 150 miles
    4. 1500 miles

  7. At convergent plate boundaries of oceanic and continental crust:

    1. oceanic crust is subducted
    2. continental crust is subducted
    3. oceanic crust is created
    4. crustal rifting occurs
    5. no associated volcanism occurs

  8. One remarkable realization associated with the discovery of seafloor spreading was that:

    1. the crust of continents is denser than that of oceans
    2. mountains are denser than the mantle
    3. compared to continents, the crustal floor of the oceans is very young
    4. the Earth's magnetic field arises from the upper mantle
    5. the Earth's magnetic field is restricted to oceanic ridges

  9. Which segment of the Atlantic Ocean opened first?

    1. northern
    2. central
    3. southern
    4. all of it opened at the same time

  10. Which one of the following statements best defines Pangaea?

    1. all of the Earth's continental masses together
    2. all of the continents of the Southern Hemisphere, only
    3. all of the continents of the Northern Hemisphere, only
    4. Africa, Madagascar, and the Indian subcontinent, only
    5. Europe, Greenland, and North America, only

  11. If the pacific plate and the North American plate continue to move in the same sense Los Angeles and San Francisco will lie at the same latitude:

    1. True
    2. False

  12. I saw a bumper sticker that said "Reunite Gondwana Land". Which of the following would not be part of this reconstruction?

    1. Antarctica
    2. India south of the Himayalays
    3. Australia
    4. Africa, Madagascar, and the Indian subcontinent, only
    5. North America

  13. Loihi excites geologists because it represents a:

    1. new instrument for detecting volcanic gases
    2. new instrument for detecting lava composition
    3. satellite that can monitor worldwide volcanic activity
    4. volcano that will become a new Hawaiian island
    5. satellite that can monitor worldwide earthquake activity

The Universe

  1. With the exception of Pluto, the outer planets:

    1. are bigger and higher density
    2. are bigger and lower density
    3. are smaller and higher density
    4. are smaller and lower density

  2. Stishovite (recall form Chapter 2) and quartz are polymorphs. The fundamental difference is that in stishovite the silicon ion is surrounded by 6 oxygens where as in quartz the silicon ion is surrounded by 4 oxygens. Therefore, in an impact structure which polymorph would form if the pressure was sufficiently high?

    1. quartz
    2. stishovite

  3. All of the planets have at least one moon:

    1. True
    2. False

  4. Venus has a higher albedo than Earth. Therefore, Venus absorbs more of the incident solar radiation than Earth.

    1. True
    2. False

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