Ch 7

Which of the following worlds have the thinnest lithospheres? A) Mercury and Venus B) Earth and Mars C) Earth and Venus D) Earth and the Moon E) Venus and the Moon

C

Which of these is the dominant mechanism for the removal of carbon dioxide from the atmosphere? A) subduction B) photosynthesis in plants C) dissolving carbon dioxide in seawater D) formation of carbonate-rich rocks at the seafloor

C

Which two geological processes appear to have been most important in shaping the present surface of Venus? A) tectonics and erosion B) volcanoes and erosion C) volcanoes and tectonics D) impacts and volcanoes E) impacts and tectonics

C

Why does Earth have the strongest magnetic field among the terrestrial worlds? A) It is the most volcanically active world. B) It is the only one that has a metallic core. C) It is the only one that has both a partially molten metallic core and reasonably rapid rotation. D) It rotates much faster than any other terrestrial world. E) It is by far the largest terrestrial world.

C

Why is continental crust lower in density than seafloor crust? A) Continental crust is made from volcanic rock called basalt, which is lower in density than what the seafloor crust is made from. B) Continental crust is actually denser than seafloor crust. C) Continental crust is made from remelted seafloor crust and therefore only the lower-density material rises to form it. D) Seafloor crust is more compact due to the weight of the oceans, but it is made of the same material as the continental crust. E) Continental crust is made of rock, while seafloor crust has more metals.

C

How have we been able to construct detailed maps of surface features on Venus? A) by using radar from spacecraft that were sent to orbit Venus B) by studying Venus with powerful telescopes on spacecraft that were sent to orbit Venus C) by studying Venus from Earth with powerful telescopes D) by making computer models of geological processes on Venus E) by landing spacecraft on the surface for close-up study

A

In the greenhouse effect, what is the direct cause of extra heating of the Earth's surface? A) Additional carbon dioxide makes the atmosphere more opaque to infrared light, trapping part of the blackbody radiation that would normally escape into space. B) Additional carbon dioxide makes the atmosphere more transparent to infrared light, allowing the sun to more directly heat the surface. C) Additional carbon dioxide makes the atmosphere denser, and thus heat passes through it more slowly.

A

Rank the five terrestrial worlds in order of size from smallest to largest. A) Moon, Mercury, Mars, Venus, Earth B) Mercury, Moon, Mars, Earth, Venus C) Mercury, Moon, Venus, Earth, Mars D) Moon, Mercury, Venus, Earth, Mars E) Mercury, Venus, Earth, Moon, Mars

A

The three principal sources of the internal heat of terrestrial planets are A) accretion, differentiation, and radioactivity. B) conduction, convection, and eruption. C) convection, differentiation, and eruption. D) accretion, differentiation, and eruption. E) conduction, differentiation, and accretion.

A

Volcanism is more likely on a planet that A) has high internal temperatures. B) is closer to the Sun. C) doesn't have an atmosphere or oceans. D) is struck often by meteors and solar system debris.

A

What drives the motion of the continental plates on Earth? A) convection cells in the mantle B) tidal forces C) Earth's magnetic field D) rotation of the liquid core E) lava flows in trenches along the sea floor

A

When we see a region of a planet that is not as heavily cratered as other regions, we conclude that A) the surface in the region is younger than the surface in more heavily cratered regions. B) the planet is rotating very slowly and only one side was hit by impactors. C) the surface in the region is older than the surface in more heavily cratered regions. D) there is little volcanic activity to create craters. E) the planet formed after the age of bombardment and missed out on getting hit by leftover planetesimals.

A

Which of the following describes impact cratering? A) the excavation of bowl-shaped depressions by asteroids or comets striking a planet's surface B) the eruption of molten rock from a planet's interior to its surface C) The disruption of a planet's surface by internal stresses D) the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather

A

Which of the following has virtually no effect on the internal structure of a planet? A) its magnetic field B) its mass C) its composition D) its size

A

Which of the following worlds has the most substantial atmosphere? A) Venus B) the Moon C) Mercury D) Mars

A

Which of the terrestrial worlds has the strongest magnetic field? A) Earth B) Mars C) the Moon D) Venus E) Mercury

A

Why does Mars have more extreme seasons than Earth? A) because it has a more eccentric orbit B) because it has a larger axis tilt C) because it is farther from the Sun D) because it has more carbon dioxide in its atmosphere E) all of the above

A

Deep trenches in the ocean mark places where A) plates pull apart, leaving great rifts in the crust. B) one plate slides under another, returning older crust to the mantle. C) plates slip sideways relative to one another. D) plates push together, creating ocean mountain chains. E) hot mantle material rises upward and spreads sideways, pushing the plates apart.

B

If the Earth were to warm up a bit, what would happen? A) The ice caps would melt and cool the Earth back to its normal temperature. B) Carbonate materials would form in the oceans more rapidly, the atmospheric CO2 content would decrease, and the greenhouse effect would weaken. C) Carbonate materials would form in the oceans more slowly, the atmospheric CO2 content would increase, and the greenhouse effect would strengthen. D) Carbonate materials would form in the oceans more rapidly, the atmospheric CO2 content would decrease, and the greenhouse effect would strengthen. E) There would be a runaway greenhouse effect, with the Earth becoming ever hotter until the oceans evaporated as may have happened on Venus).

B

The core, mantle, and crust of a planet are defined by differences in their A) Temperature B) Density C) Geological Activity D) Strength

B

What are the circumstances under which convection can occur in a substance? A) when the substance is strongly shaken or disturbed by a strong wind B) when the substance is strongly heated from underneath C) when dense material is being added to the substance D) when the substance is strongly cooled from underneath E) when the substance is subjected to a strong magnetic field

B

Which of the following best describes convection? A) It is the process in which warm material gets even warmer and cool material gets even cooler. B) It is the process in which warm material expands and rises while cool material contracts and falls. C) It is the process in which bubbles of gas move upward through a liquid. D) It is the process in which a liquid separates according to density, such as oil and water separating in a jar. E) It is the process by which rocks sink in water.

B

Which of the following describes volcanism? A) the excavation of bowl-shaped depressions by asteroids or comets striking a planet's surface B) the eruption of molten rock from a planet's interior to its surface C) the disruption of a planet's surface by internal stresses D) the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather

B

Why can we not depend on the natural CO2 cycle to lower carbon-dioxide levels? A) It only removes small amounts of CO2 from the atmosphere. B) It operates too slowly. C) There is no natural CO2 cycle.

B

Why is Mars red? A) Its atmosphere scatters blue light more effectively than red light. B) Its surface rocks were rusted by oxygen. C) It is made primarily of red clay. D) Its surface is made of ices that absorb blue light. E) Its surface is made of ices that absorb red light.

B

From where did the oxygen in the Earth's atmosphere originate? A) atmospheric bombardment B) chemical reactions between gas in the upper atmosphere and the solar wind C) outgassing from volcanoes D) photosynthesis from plant life and single-celled organisms E) oxidation of surface rocks

C

Given the current emission rate of carbon dioxide, how much will the Earth's average temperature increase over the next century? A) 0°C B) 0-3°C C) 3-5°C D) 7-10°C E) 5-7°C

C

How deep is an impact crater compared to its width? A) 50-100% B) 30-40% C) 10-20% D) 100-200% E) 1-10%

C

How did the lunar maria form? A) The early bombardment created heat that melted the lunar surface in the regions of the maria. B) The giant impact that created the Moon left smooth areas that we call the maria. C) Large impacts fractured the Moon's lithosphere, allowing lava to fill the impact basins. D) Volatiles escaping from the Moon's interior heated and eroded the surface in the regions of the maria. E) The maria are the result of gradual erosion by micrometeorites striking the Moon.

C

Mars' atmosphere is mostly carbon-dioxide. Why does it not experience a runaway greenhouse effect like Venus? A) It does not have enough additional water to magnify the warming. B) It is protected by its magnetic field. C) Its atmosphere is too thin.

C

Ridges in the middle of the ocean are places where A) plates slip sideways relative to one another. B) plates push together, creating ocean mountain chains. C) hot mantle material rises upward and spreads sideways, pushing the plates apart. D) one plate slides under another, returning older crust to the mantle. E) hot mantle material rises upward, creating volcanic islands.

C

Under what circumstances can differentiation occur in a planet? A) The planet must have an atmosphere. B) The planet must be made of both metal and rock. C) The planet must have a molten interior. D) The planet must be geologically active, that is, have volcanoes, planetquakes, and erosion from weather. E) The planet must have a rocky surface.

C

What process has shaped Earth's surface more than any other? A) acid rain B) wind erosion C) plate tectonics D) volcanism E) impact cratering

C

What type of stresses broke Earth's lithosphere into plates? A) volcanism, which produced heavy volcanoes that bent and cracked the lithosphere B) impacts of asteroids and planetesimals C) the circulation of convection cells in the mantle, which dragged against the lithosphere D) internal temperature changes that caused the crust to expand and stretch E) cooling and contracting of the planet's interior, which caused the mantle and lithosphere to be compressed

C

Which of the following can act like a long-term "thermostat" for the Earth's average temperature? A) heat stored in the Earth's liquid core B) radioactive elements trapped in the Earth's mantle C) the carbon dioxide cycle D) heat stored in the Earth's magnetosphere

C

Which of the following describes tectonics? A) the excavation of bowl-shaped depressions by asteroids or comets striking a planet's surface B) the eruption of molten rock from a planet's interior to its surface C) the disruption of a planet's surface by internal stresses D) the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather

C

Which of the following does not have a major effect in shaping planetary surfaces? A) tectonics B) volcanism C) magnetism D) erosion E) impact cratering

C

Which of the following gases absorbs ultraviolet light best? A) oxygen B) carbon dioxide C) ozone D) hydrogen E) nitrogen

C

Which of the following is not a product of outgassing? A) water B) carbon dioxide C) oxygen D) nitrogen

C

A planet is most likely to have tectonic activity if it has A) low surface gravity. B) low internal temperature. C) a dense atmosphere. D) high internal temperature. E) high surface gravity.

D

Earth's atmosphere contains only small amounts of carbon dioxide because A) carbon dioxide dissolves in water, and most of it is now contained in the oceans and carbonate rocks. B) chemical reactions with other gases destroyed the carbon dioxide and replaced it with the nitrogen that is in the atmosphere now. C) the Earth's volcanoes did not outgas as much carbon dioxide as those on Venus and Mars. D) most of the carbon dioxide was lost during the age of bombardment. E) Earth doesn't have as strong a greenhouse effect as is present on Venus.

D

How large is an impact crater compared to the size of the impactor? A) 100 times larger B) the same size C) 10-20 percent larger D) 10 times larger E) 1,000 times larger

D

Spacecraft have landed on all the terrestrial worlds except A) Venus. B) Moon. C) Mars. D) Mercury

D

Suppose Earth's atmosphere had no greenhouse gases. Then Earth's average surface temperature would be A) 15°C, or about the same as it is now. B) 0°C, or about the freezing point for water. C) 10°C or about 5°C cooler than it is now. D) -16°C, which is well below freezing. E) 20°C, or about 5°C warmer than it is now.

D

The lithosphere of a planet is the layer that consists of A) the softer rocky material of the mantle. B) material between the crust and the mantle. C) the lava that comes out of volcanoes. D) the rigid rocky material of the crust and uppermost portion of the mantle. E) material above the crust.

D

The relatively few craters that we see within the lunar maria A) are volcanic in origin, rather than from impacts. B) are sinkholes that formed when sections of the maria collapsed. C) were created by the same large impactor that led to the formation of the maria. D) were formed by impacts that occurred after those that formed most of the craters in the lunar highlands. E) were formed by impacts that occurred before those that formed most of the craters in the lunar highlands.

D

There are no auroras on Venus because it A) lacks atmospheric oxygen. B) is too hot. C) lacks strong winds. D) Lacks strong magnetic field.

D

Valles Marineris is a(n) A) extensive plain on Mars. B) large canyon on Venus. C) large canyon on Mars. D) huge series of cliffs on Mercury. E) large valley on the Moon.

D

What are the conditions necessary for a terrestrial planet to have a strong magnetic field? A) a rocky mantle only B) fast rotation only C) a molten metallic core only D) both a molten metallic core and reasonably fast rotation E) both a metal core and a rocky mantle

D

What is the most important factor that determines the thickness, and therefore strength, of the lithosphere? A) Composition B) Distance of plane C) Pressure D) Internal Temperature

D

Which internal energy source produces heat by converting gravitational potential energy into thermal energy? A) differentiation B) accretion C) radioactivity D) both A and B E) all of the above

D

Which of the following describes erosion? A) the excavation of bowl-shaped depressions by asteroids or comets striking a planet's surface B) the eruption of molten rock from a planet's interior to its surface C) the disruption of a planet's surface by internal stresses D) the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather

D

Which of the following most likely explains why Venus does not have a strong magnetic field? A) It is too large. B) It has too thick an atmosphere. C) It is too close to the Sun. D) Its rotation is too slow. E) It does not have a metallic core.

D

Which of the following show evidence of ancient river beds? A) Mercury B) Venus C) the Moon D) Mars E) all of the above

D

Why does the burning of fossil fuels increase the greenhouse effect on Earth? A) Burning produces infrared light, which is then trapped by existing greenhouse gases. B) Burning fuel warms the planet. C) Burning depletes the amount of ozone, thereby warming the planet. D) Burning releases carbon dioxide into the atmosphere. E) All the above

D

Why would the weather become more severe as the greenhouse effect increased? A) The depleted ozone layer would let in more particles from the solar wind. B) Warming would dry out the atmosphere and the crust, leading to devastation of the Earth through more meteor bombardment and volcanism. C) Warming of the planet would lead to terrible droughts and reduce the amount of water on the Earth. D) Warming would increase the evaporation of the oceans, leading to more water in the atmosphere and more frequent and severe storms. E) all of the above

D

How fast do tectonic plates move on Earth? A) about 1 mile per hour B) a few kilometers per century C) a few centimeters per century D) quite fast, but only during earthquakes E) a few centimeters per year

E

How is the atmosphere of a planet affected by the rotation rate? A) Faster rotation rates raise surface temperatures and thus determine how much material is gaseous versus icy or liquid. B) The rotation rate determines how long the planet is able to retain its atmosphere. C) The rotation rate determines how much atmosphere a planet has. D) Faster rotation rates raise the atmospheric temperature. E) Faster rotation rates produce stronger winds.

E

In what ways is Earth different from the other terrestrial planets? A) Most of its surface is covered with liquid water. B) It has oxygen in its atmosphere. C) Life can be found almost everywhere. D) Its lithosphere is broken into plates that move around. E) All of the above are true.

E

Of the four gases CO2, H2O, N2, and O2, which are greenhouse gases? A) all except O2 B) CO2 and N2 C) all four D) only CO2 E) CO2 and H2O

E

The Caloris Basin on Mercury covers a large region of the planet, but few smaller craters have formed on top of it. From this we conclude that A) only very large impactors hit Mercury's surface in the past. B) Mercury's atmosphere prevented smaller objects from hitting the surface. C) erosion destroyed the smaller craters that formed on the basin. D) the Caloris Basin was formed by a volcano. E) the Caloris Basin formed toward the end of the solar system's period of heavy bombardment.

E

The terrestrial planet cores contain mostly metal because A) radioactivity created metals in the core from the decay of uranium. B) convection carried the metals to the core. C) the entire planets are made mostly of metal. D) metals condensed first in the solar nebula and the rocks then accreted around them. E) metals sank to the center during a time when the interiors were molten throughout.

E

What are fossil fuels? A) any fuel that is extracted from the interior of the Earth B) any fuel that releases CO2 into the atmosphere upon burning C) mineral-rich deposits from ancient seabeds D) carbonate-rich deposits from ancient seabeds E) the carbon-rich remains of plants that died millions of years ago

E

What are greenhouse gases? A) gases that transmit infrared light B) gases that transmit visible light C) gases that absorb ultraviolet light D) gases that absorb visible light E) gases that absorb infrared light

E

What kind of surface features may result from tectonics? A) cliffs B) volcanos C) valleys D) mountains E) all of the above

E

Which of the following planets has the least substantial atmosphere? A) Venus B) Neptune C) Mars D) Earth E) Mercury

E

Which of the following statements about the greenhouse effect is true? A) Without the naturally occurring greenhouse effect, Earth would be too cold to have liquid oceans. B) A weak greenhouse effect operates on Mars. C) One result of an increased greenhouse effect on Earth may be an increased number of severe storms. D) The burning of fossil fuels increases the greenhouse effect on Earth because of the release of carbon dioxide. E) All of the above are true.

E

Why do we think Mercury has so many tremendous cliffs? A) They are almost certainly volcanic in origin, carved by flowing lava. B) They were probably carved in Mercury's early history by running water. C) They probably formed when a series of large impacts hit Mercury one after the other. D) They represent one of the greatest mysteries in the solar system, as no one has suggested a reasonable hypothesis for their formation. E) They were probably formed by tectonic stresses when the entire planet shrank as its core cooled.

E

Where is most of the water on Mars? A) distributed evenly throughout its atmosphere B) in deep underground deposits C) frozen on the peaks of its tall volcanoes D) in its polar caps and subsurface ground ice E) in its clouds

d