Evidence suggests that Earth is about 4.6 billion years old, even though no Earth rocks have been found that can be dated at more than 4 billion years old. This discrepancy is most likely caused by Earth’s original crust being

1. difficult to date so precisely.
   
2. subject to extensive erosion.
   
3. blasted away during Earth’s formation.
   
4. destroyed by solar radiation.
   

Which of the following is the best evidence that Earth’s continents were once in vastly different positions than they are today?

1. Penguins are found only in the Southern Hemisphere.
   
   
2. Fossils of tropical plants are found in Antarctica.
   
3. Volcanoes encircle the Pacific Ocean.
   
4. Major rivers form deltas from continental erosion.
   

Notes

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Which of the following provides evidence for plate tectonics?

1. sea-floor topography
   
2. ocean currents
   
3. Coriolis effect
   
4. atmospheric temperatures
   

Notes

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A rift valley is evidence of which kind of plate

1. convergent
   
2. divergent
   
3. transform
   
4. uniform
   

Notes

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The convergence of two continental plates would produce

1. island arcs.
   
2. rift valleys
   
3. folded mountains
   
4. trenches
   

Notes

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It is generally true that igneous rocks

1. contain primarily evaporites.
   
2. can be scratched with a penny.
   
3. normally contain fossils.
   
4. are composed of silicate minerals.
   

Notes

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Relative cooling rates of igneous intrusive rocks can be estimated by comparing rocks’

1. crystal sizes.
   
2. composition.
   
3. density.
   
4. chemical reactivity.
   

Notes

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Earthquake vibrations are detected, measured, and recorded by instruments called

1. sonargraphs
   
2. seismographs
   
3. Richter scales.
   
4. magnetometers.
   

Notes

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At which location would earthquakes be least likely to occur?

1. 1
   
2. 2
   
3. 3
   
4. 4
   

Notes

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The Richter scale measures which of the following earthquake characteristics?

1. intensity
   
2. magnitude
   
3. frequency
   
4. probability
   

Notes

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Which type of volcano would be the least explosive?

1. cinder cone
   
2. stratovolcano
   
3. shield volcano
   
4. composite cone
   

Notes

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Which of the following energy sources is most likely to be abundant in California due to its position on a plate boundary?

1. wind
   
2. nuclear
   
3. solar
   
4. geothermal
   

Notes

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What energy resource is made possible by the volcanic activity in California?

1. hydroelectricity
   
2. nuclear power
   
3. geothermal energy
   
4. solar energy
   

Notes

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Geothermal energy is possible where there is

1. wind
   
2. oil
   
3. coal
   
4. magma
   

Notes

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The Long Valley Caldera in east-central California was formed by a massive volcanic eruption about 760,000 years ago. Since then, it has erupted several times. Of the following, which would be least likely to indicate that another eruption will soon occur?

1. recurring earthquakes in the vicinity
   
2. decreases in precipitation in the area
   
3. changes in gas emissions from the caldera
   
4. uplifting of the floor of the caldera
   

Notes

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Earthquake activity in California is primarily caused by

1. the lowering of aquifer levels.
   
2. the interaction of tides with the coast.
   
3. mining activity during the nineteenth century.
   
4. plates grinding past each other along active faults.
   

Notes

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Geothermal energy, a possible energy resource, is based on which phenomenon?

1. There are concentrations of heat in some places of Earth’s crust.
   
2. Earth’s internal energy heats its surface more than the Sun does.
   
3. Heat energy from the Sun penetrates deep into Earth.
   
4. Human activity is the largest source of heat energy on Earth.
   

Notes

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Shifts in Earth’s continents most likely caused a change in Earth’s

1. climatic regions.
   
2. mass.
   
3. orbital velocity.
   
4. atmospheric temperature.
   

Notes

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Scientists have found fossils of tropical plants in Antarctica. How could tropical plants have grown in Antarctica?

1. At one time, Earth’s entire surface was a tropical rain forest.
   
2. At one time, Antarctica was located closer to the equator.
   
3. The rotation of Earth has increased, causing cooling of the atmosphere.
   
4. Catastrophic volcanic eruptions melted the ice and exposed the soil to sunlight.
   

Notes

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The table above lists the gases coming from a modern Hawaiian volcano. If ancient volcanoes gave off the same gases, which gas would have been most helpful in the development of early life-forms that could carry out photosynthesis?

1. N₂
   
2. SO₂
   
3. CO₂
   
4. Cl₂
   

Notes

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