Deck 6: Exploring Terrestrial Surface Processes and Atmospheres

Question 1

All of the terrestrial planets have plate tectonics with converging and spreading plates similar to Earth's.

Answer 1

False

Question 2

A large planet will cool off faster than a small planet because it is emitting energy at a faster rate.

Answer 2

False

Question 3

The Moon has relatively few craters and is said to be geologically active.

Answer 3

False

Question 4

Mars has a thin,almost cloudless atmosphere that permits a clear view of the surface and the most striking visible features are the polar ice caps.

Question 5

Naked-eye observations of Mercury are best made at midnight.

Question 6

Venus's atmosphere is extremely hot and dense.

Question 7

Opposite the Caloris Basin,a huge crater on Mercury,there exists a jumbled,hilly region theorized to be caused by seismic waves that were focused after the impact.

Question 8

Venus appears almost completely featureless with neither clearly noticeable continents nor mountains.

Question 9

Valles Marineris on Mars is thought to be a rift valley,a feature created when a planet's crust breaks apart a fault line.

Question 10

No spacecraft have successfully landed on the surface of Mars,but it has been mapped with satellites orbiting the planet.

Question 11

Venus has a relatively thin crust that undergoes wrinkling and flaking;this model is called "flake tectonics."

Question 12

Mars's atmosphere experiences a runaway icehouse effect where CO₂ is pulled from the atmosphere,lowering the temperature even more.

Question 13

Hot-spot volcanoes on Earth are only found on the continent of Australia.

Question 14

Mercury's scarps,numerous long cliffs,were probably formed as the planet cooled and contracted.

Question 15

Jupiter's moon,Io,may have as many as 300 active volcanoes on its surface.

Question 16

Mars's atmosphere has always been thin and cold.

Question 17

X-rays were used to map the surface of Venus.

Question 18

An impact crater will always reproduce the shape of the original impacting object.

Question 19

Venus's craters are uniformly scattered across the planet's surface suggesting that the entire surface of the planet is essentially the same age.

Question 20

Europa is the only world in the solar system other than Earth on which there is liquid water.

Question 21

In order to measure Venus's rotation,it was necessary to send a beam of electromagnetic radiation through the cloud layer.This electromagnetic radiation was

A) ultraviolet.
B) visible.
C) infrared.
D) short-wave radio or microwave.

Question 22

Craters on Mercury appear to have been produced by

A) impacts by objects from space continuously throughout the planet's history,including very recently in geological time.
B) volcanic eruptions early in the planet's history.
C) successive expansion and contraction of the planet's surface,caused by intense heating by the Sun and severe cooling during rotation,because the craters appear to be in irregular lines across the surface.
D) impacts from objects early in the planet's history.

Question 23

The most common surface features on Venus are

A) ancient river valleys and huge floodplains.
B) impact craters.
C) volcanoes and lava flows.
D) evidence of plate tectonic motion,including long mountain ranges and subduction troughs.

Question 24

A distinct area of unusually jumbled,hilly terrain has been found on Mercury.This terrain was formed by

A) upwelling of magma while Mercury was still hot enough for its mantle to be tectonically active.
B) the impact of a large comet.
C) an intense shower of meteoroids near the end of the heavy bombardment era.
D) the focusing of seismic waves generated by the Caloris impact.

Question 25

Despite the planet's close proximity to the Sun,water ice remains on the surface of Mercury because it

A) is permanently shielded from the Sun by crater walls at the north and south poles.
B) exists as permafrost below the thermally insulating surface,being exposed only by occasional impacts.
C) is continuously replenished by fresh impacts from comets.
D) is continuously replenished by condensation of water vapor from volcanoes.

Question 26

Caloris Basin,a huge circular region on Mercury surrounded by rings of mountains,appears to have been produced by

A) the impact of a massive object in the early phases of the planet's formation,soon after the initial cratering period.
B) wind erosion from huge atmospheric storms,similar to super-hurricanes on Earth or the Great Red Spot on Jupiter.
C) successive expansion and contraction of the planet's surface by intense solar heating and severe cooling as the planet rotated,causing buckling in a similar way to the formation of the North American Rocky Mountains or the South American Andes.
D) the lava flow from a large and long-lived volcano that formed the mountains in a similar manner to the formation of the Hawaiian Islands on Earth.

Question 27

The Hawaiian Islands experience continuous volcanic activity because they

A) lie right on a boundary between tectonic plates.
B) happen to be at a focal point for seismic waves from earthquakes around the Pacific Ocean.
C) are in the center of a major ocean.
D) lie directly above a hot-spot plume in Earth's interior.

Question 28

Tectonic activity on Venus differs from that on Earth in that

A) active crustal deformation appears to be completely absent.
B) the lithosphere appears to be softer or more plastic and cannot support the creation and motion of solid plates (flake tectonics).
C) the lithosphere appears to be cooler and thicker and is therefore too rigid to break up into moving plates.
D) mantle convection appears to be more vigorous and has broken the lithosphere into a multitude of small plates instead of a few large ones.

Question 29

The overall geography of Mars can be best summarized as

A) major volcanoes in the northern hemisphere,extensively cratered plains in the southern hemisphere,and the hemispheres separated by one major valley system.
B) moving lithospheric plates whose motions have produced long,folded mountain chains,deep subduction trenches,and several large rift valleys.
C) smooth plains where continuous resurfacing by ongoing volcanic activity has hidden older impact craters and other details.
D) mostly rolling plains,with several volcanoes on two continent-sized uplands.

Question 30

Venus appears to be very bright in our skies at certain times because

A) even though its surface is very dark,it is relatively close to the Sun.
B) it is glowing from the heat of its surface,where the temperature is 750 K.
C) its rocky surface is shiny,like the surface of new volcanic lava.
D) it is relatively close to the Sun,Earth is close to it,and it is covered by very reflective clouds.

Question 31

In what way was the production of the Hawaiian Islands on Earth similar to the production of some of the major mountains on Mars and Venus?

A) They were produced by hot-spot volcanism and upflow of heat from below.
B) They were produced by impacts of massive asteroids during the ancient heavy bombardment period and are now being eroded by wind and water.
C) They were produced by slow buildup of coral reefs in ancient oceans.
D) They were formed by upthrust from collisions of two tectonic plates.

Question 32

What evidence would a planetary geologist use to identify a "young" crater on Mercury?

A) Infrared and photographic results showing evidence of water released recently from the permafrost by the impact
B) Sharper rim and central peak compared to older craters,whose features would have suffered significant erosion by wind and dust
C) Lighter-colored central region,because older craters would have acquired a layer of dark dust over time
D) Few,if any,smaller craters within it or on its rim

Question 33

The reason Venus has very few impact craters compared with the Moon is believed to be that

A) lava flows have covered all but the most recent craters.
B) Venus formed closer to the Sun than did the Moon,where the cratering rate was much lower.
C) the surface of Venus has been subducted into the mantle over periods of several hundred million years.
D) erosion due to wind and rainfall has worn away all but the most recent craters.

Question 34

The surface features and topology of Venus have been determined primarily by

A) radar methods from Earth and from Venus-orbiting spacecraft detecting reflected radio and microwaves from the surface.
B) surface-lander vehicles that have explored the surface.
C) visible light and UV photography from the Hubble Space Telescope and Earth-bound telescopes.
D) balloon-borne spacecraft launched into the Venus atmosphere by spacecraft.

Question 35

When were most of the existing lava plains formed on the surface of Mercury?

A) Never.There is no evidence of lava flows on the surface of Mercury.
B) When Mercury was first formed,about 4.5 billion years ago
C) At the end of the era of heavy bombardment,about 3.8 billion years ago
D) When the crust wrinkled to form the scarps

Question 36

Which one of the following pieces of evidence SUPPORTS the existence of tectonic activity in the Martian past?

A) The crust is everywhere thicker than Earth's crust.
B) There are large,isolated hot-spot volcanoes.
C) Valles Marineris,a long valley system,has been observed.
D) There is no planet-wide magnetic field.

Question 37

When Venus is seen at inferior conjunction,a ring of light is seen around it.What does this tell us about Venus?

A) Venus has auroral displays similar to those on Earth that extend over the whole planet.
B) Venus has a thick atmosphere that scatters sunlight toward us.
C) The surface of Venus is so hot that it glows,even on its dark side.
D) Venus is sufficiently massive that its gravitational field bends sunlight around the planet toward us.

Question 38

What is believed to be the cause of the long,meandering scarps (cliffs)observed on Mercury?

A) Shrinkage of the planet as Mercury cooled
B) Large impacts near the end of the early period of heavy bombardment
C) Volcanic eruptions along crustal faults over hot spots in the mantle
D) Crustal movement due to convection in the mantle,similar to continental drift on Earth but to a much smaller extent

Question 39

A shield volcano is a

A) volcanic dome on the side of a larger volcano that shields the surrounding plains from inundation by lava from the main vent.
B) very broad volcano with gently sloping sides,similar in shape to an ancient Greek shield.
C) tall volcano with steep sides,similar in shape to the central ornament of an ancient Roman shield.
D) vast lava flood-plain originating from a ground-level fissure,similar in size and topography to the Canadian Shield rock formation.

Question 40

Which of the planets fits the following

A) Venus
B) Jupiter
C) Mars
D) Mercury

Question 41

The sulfur compounds that are detected in the clouds above the surface of Venus have most probably come from

A) recent eruptions of volcanoes,spewing gases and dust high into the atmosphere.
B) meteoritic material that burned up as it fell into Venus's atmosphere.
C) intense wind storms that have carried surface dust high into the atmosphere.
D) the solar wind,having been captured by the intense magnetic field of the planet.

Question 42

Water has been discovered on Mars.In what form does it exist?

A) Only as atmospheric water vapor,never condensing as liquid water or solid ice
B) As a liquid,flowing continuously along the numerous flood valleys and meandering stream beds
C) As permafrost,polar icecaps,and atmospheric vapor
D) As a liquid in lakes and rivers

Question 43

The pressure of the atmosphere of Mars-primarily carbon dioxide (CO₂)-compared with the atmospheric pressure at Earth's surface,is

A) extremely small (less than 1 millionth).
B) about 90 times greater.
C) less than 1/100.
D) about the same.

Question 44

The polar caps on Mars are most likely made up of

A) water and CO₂ ices.
B) light-colored dust blown there by intense dust storms and large dust devils.
C) volcanic outflow of light-colored lava and dust similar to that produced by Earth-based volcanoes.
D) sulfur dioxide and sulfur compounds.

Question 45

The major volcanoes on Mars have formed

A) in regions of ridges where the crust is being compressed and buckled without being subducted.
B) directly above stationary hot spots in the mantle.
C) on long,interconnecting ridges and rifts,where magma rising from the mantle is pushing the crust apart.
D) in mountain belts,where the crust is being subducted into the mantle.

Question 46

The reason for the surprising result measured by the Viking Lander spacecraft on Mars,that the pressure readings of the atmosphere seemed to go down continuously after the spacecraft landed,is that

A) the sensors were measuring outgassing of the spacecraft as it adjusted to the very low atmospheric pressure on Mars.
B) the sensors were slowly deteriorating in the intense solar UV radiation,making them progressively less sensitive.
C) the major constituent of the atmosphere,CO₂,was freezing into dry ice flakes as winter approached.
D) the wake caused by the landing of the spacecraft acted like a hole in the atmosphere to allow the surface gases to escape.

Question 47

On Earth,volcanoes are of two basic types: shield volcanoes (lava welling up from local hot spots)and cone volcanoes (caused by the collision of tectonic plates).In surveying the inner part of the solar system (leaving out Earth),namely Mercury,Venus,the Moon,and Mars,we find

A) no volcanoes,either active or dormant.
B) shield volcanoes only.
C) cone volcanoes only.
D) volcanoes of both types.

Question 48

Mars has a crust that is everywhere thicker than Earth's crust.What is the primary reason for this?

A) Mars,being smaller,cooled more rapidly.
B) Mars is cooler because it is farther from the Sun.
C) Mars rotates too slowly to allow the crust to remain fluid.
D) Mars rotates too rapidly to allow the crust to remain fluid.

Question 49

On the basis of the surface and atmospheric conditions existing on Mars today,why could there be no permanent liquid water on its surface?

A) The water would boil and evaporate rapidly under the low atmospheric pressure or freeze to ice at the low surface temperatures.
B) It would have reacted chemically with the surface rocks.
C) The UV radiation from the Sun would have dissociated the water molecules into hydrogen (which would leave the planet)and oxygen,which is still present.
D) It would have soaked into the porous surface of Mars.

Question 50

The cloud structure of Venus can best be described as

A) a perpetual thick cloud layer extending almost to ground level.
B) a perpetual thick cloud layer with a haze layer under it and clear air below the haze layer down to the surface.
C) mostly clear sky with occasional thin H₂O and dust clouds.
D) isolated cloud systems constantly forming and dissipating with clear sky between them.

Question 51

Venus has a higher surface temperature than Mercury.Which of the following is an explanation for this?

A) Venus is closer to the Sun than Mercury is.
B) Venus has a dense atmosphere of carbon dioxide.
C) Venus is still contracting gravitationally and thus gives out more radiation than it receives.
D) Venus has a higher albedo (reflectance)than Mercury.

Question 52

In which of the following ways are Venus and Mars alike,yet markedly different from Earth?

A) Their surface temperatures are both much higher than that of Earth.
B) They are both perpetually shrouded in clouds.
C) They both have either active or extinct volcanoes on their surfaces.
D) Their atmospheres are made up primarily of carbon dioxide.

Question 53

The huge volcano Olympus Mons on Mars and those that make up the Hawaiian Islands on Earth appear to be very similar,but they differ in one important respect.What is this difference?

A) Olympus Mons is very close to the Martian north pole,where tidal stress from the Sun is small,whereas the Hawaiian Islands are close to the equator,where tidal stresses from the Moon and Sun have formed the fault along which they lie.
B) Olympus Mons is formed almost solely of sulfur,whereas the Hawaiian Islands are formed of rock from the solidification of lava.
C) Olympus Mons is a very steep-sided volcano,whereas the volcanoes of Hawaii are rather flat,with gentle slopes right up to their calderas.
D) In the Hawaiian Islands,plate tectonic motion has moved the Pacific Ocean floor over a hot spot,forming a line of volcanoes.No such motion occurred for Olympus Mons over an equivalent hot spot on Mars.

Question 54

The surface and near-surface atmospheric conditions on Venus are

A) no atmosphere,very variable temperature.
B) dense methane,ammonia,and H₂O atmosphere,low temperature.
C) CO₂ atmosphere,low pressure,and low temperature.
D) CO₂ atmosphere,high pressure,and high temperature.

Question 55

The atmosphere of Venus is observed to contain almost no water.This is apparent because

A) the water is locked up as ice (permafrost)beneath the surface of the planet.
B) Venus is so hot that whatever water there was simply evaporated into space because it was lighter than the major constituent,carbon dioxide.
C) solar UV light dissociated the water into hydrogen and oxygen;the hydrogen then escaped into space and the oxygen combined with other substances.
D) Venus has never had a significant amount of water,having formed closer to the Sun than did Earth,where water in the solar nebula could not condense.

Question 56

Evidence of hot-spot volcanoes caused by hot,rising plumes under the planet's surface is present on Venus and Mars,as well as on Earth.What distinguishes those on Earth from those on the other planets?

A) Those on the other planets occurred on tectonic plate boundaries,and they are therefore distorted and have spread over the planet surface.
B) Plate tectonics on all three planets has formed chains of small volcano cones,but those on Earth have all occurred under the sea and are hidden.
C) This type of volcano occurred only at the spin axes or poles of the other planets,where tidal stress was greatest,whereas on Earth they occurred near the equator.
D) Plate tectonics on Earth has moved the hot-spot volcanic site continuously over recent geological time,whereas no such movement has occurred on Venus or Mars.

Question 57

How did the inner planets,Venus and Earth,acquire their original atmospheres?

A) Capture of solar-wind gases from the Sun as they streamed past the planets
B) The impact and melting of icy comets and asteroids from the planetary system and perhaps beyond
C) Gravitational capture of material from the original solar nebula by the planets
D) Outgassing of the planets through volcanoes and other vents

Question 58

Why has the greenhouse effect been much more effective in raising the surface temperature on Venus than on Earth?

A) The solar wind,the major cause of heating in the greenhouse effect,is far more intense at Venus's distance from the Sun,and Venus has no magnetic field to deflect it.
B) The oceans on Earth have acted as a thermostat in absorbing much of the heat that would otherwise have raised Earth's temperature significantly.
C) CO₂,which traps heat from the planet's surface,is the major component in the very dense Venusian atmosphere but only a minor constituent of Earth's atmosphere.
D) The surface of Venus is much more effective than that of Earth in absorbing solar visible and UV radiation.

Question 59

The Tharsis rise on Mars,a region that is higher than the surrounding plain by about 5 km (over 16,000 ft),was caused by

A) the collision of two tectonic plates.
B) the focusing of seismic waves from the impact of a massive asteroid at the diametrically opposite point on Mars.
C) an upwelling magma plume in Mars's interior,which has raised this whole region.
D) erosion of the surrounding plain by massive floods.

Question 60

Much of the water on Earth,Venus,and Mars has come from outgassing of water vapor from volcanoes.Much of the remainder is believed to have come from

A) chemical reactions,which have produced water from more complex molecules.
B) the combination of elemental hydrogen and oxygen in the atmosphere,the reaction powered by high-energy ultraviolet rays.
C) baking of rocks containing water.
D) the impacts of comets.

Question 61

The smoothest body in the solar system is

A) Mercury.
B) Europa.
C) Ganymede.
D) Enceladus.

Question 62

Which of the following processes has played the greatest role in shaping the surface of the Moon?

A) Erosion by wind and atmospheric gases
B) Impacts of interplanetary bodies of all sizes
C) Motions of tectonic plates,producing mountain ranges wherever they collide
D) Recent volcanic activity,producing large numbers of crater-like volcanic calderas

Question 63

The carbon dioxide atmosphere of Mars was much denser in Mars's early history than it is now.What process is now believed to have begun this atmospheric thinning?

A) The solar wind stripped the outer atmosphere from the planet.
B) The light CO₂ molecules escaped directly into space because of the weak gravity of Mars.
C) The CO₂ molecules were broken down by solar UV photons,creating the lighter molecules,CO and O₂,which then escaped into space.
D) The CO₂ was washed out of the atmosphere by rain.

Question 64

Many craters on the Moon are characterized by a central peak.What is the significance of this?

A) This is strong evidence that lunar craters are volcanic in origin.
B) A central peak is characteristic of an impact crater formed by a shock wave.
C) The crater has dug into the lunar surface far enough to uncover an ancient mountain range.
D) The crater was formed by impact,but it has penetrated into the lunar surface far enough to evoke lava flow,which has produced a volcanic cone.

Question 65

One of the most important sources of heat in the interiors of moons that orbit close to giant planets is

A) reflection of sunlight from the planet's surface onto the moons.
B) continuous tidal distortion from other moons and the planet.
C) absorption of thermal radiation from the planet.
D) decay of radioactive elements within the moons.

Question 66

What appears to be the "impact history" of cratering on the Moon?

A) More-or-less constant bombardment from the earliest times to the present
B) Heaviest bombardment when the Moon first formed,gradually decreasing (except for increased activity about 4 billion years ago)to light bombardment today
C) Short periods of heavy bombardment alternating with long periods of light bombardment throughout the Moon's life
D) An early period of heavy bombardment followed by a decrease in intensity (except for a spike around 4 billion years ago)and then very light bombardment to the present

Question 67

On Earth (and in the past,on Mars),volcanoes have been vital for keeping the planet warm.This is because

A) heat conducted from the molten mantle to the surface near volcanoes,where the crust is thin,is a major heat source for the atmosphere.
B) heat released along the major rift zones is the biggest source of heating for the atmosphere.
C) direct heat input by underwater volcanoes keeps the oceans from freezing.
D) they have replenished the CO₂ (a greenhouse gas)that is washed out of the atmosphere by rain.

Question 68

What is the status of the greenhouse effect on Mars at the present time?

A) It no longer exists at all.
B) It is very weak and raises the planet's temperature only a few degrees above the temperature it would have with no atmosphere at all.
C) It is weak but becoming stronger as Martian volcanoes continue to dump large amounts of CO₂ into the atmosphere.
D) It is very strong and has caused the temperature to be at least 100 degrees above the temperature it would have been with no atmosphere at all.

Question 69

A mare on the Moon is a

A) large crater with a central peak terracing along the crater walls.
B) crater shaped like a horse.
C) large area of dark material on the lunar surface.
D) large area of light material on the lunar surface.

Question 70

What is the origin of the majority of lunar craters?

A) Impacts by space probes
B) Surface collapse after loss of groundwater by evaporation
C) Volcanic explosions
D) Impacts by meteoric material

Question 71

Recent observations of Mars have revealed strong evidence that water once existed in substantial amounts on Mars.Which of the following is NOT one of these observations?

A) Teardrop-shaped islands in smooth valleys
B) Outcrops of sedimentary rocks
C) Deep meandering gullies
D) A network of linear features resembling canals

Question 72

Where did the Mars Pathfinder carrying the wheeled robot Sojourner land?

A) Very close to one of the large shield volcanoes
B) Near the northern water and CO₂ ice cap
C) On a flat,moderately cratered plain
D) In an ancient flood channel

Question 73

The eruptive plumes observed on Io are thought to most closely resemble

A) terrestrial mid-ocean ridges,where upwelling molten rock pushes the crust apart.
B) geysers,where material is shot upward by the pressure of gas produced below the surface.
C) volcanoes,producing lava flows and columns of erupting silicate ash.
D) explosions,where material is thrown upward by a single burst and then falls back to the surface.

Question 74

At what point did the greenhouse effect cease to raise the temperature of Venus?

A) When all the greenhouse gases evaporated
B) When the radiation from Venus balanced the radiation absorbed by Venus
C) When the CO₂ was dissolved in the early Venusian oceans
D) When the greenhouse gases combined with other chemicals

Question 75

The most geologically active object in the planetary system at the present time is

A) Io,a moon of Jupiter.
B) Earth's Moon.
C) Earth.
D) Mars.

Question 76

What is the most likely cause of the smooth and relatively crater-free surfaces of lunar maria?

A) Volcanic ash that rained on the surfaces of the basins in recent geological times
B) Dust storms that eroded and smoothed the surface
C) Sediments left behind after water flowed into the basins and evaporated
D) Lava flows relatively late in the geological history of the Moon

Question 77

Where is ice believed to have been discovered on the Moon?

A) In the floors of craters at the north and south poles,which are permanently shaded from the Sun
B) No ice has ever been discovered on the Moon because water cannot exist there in any form.
C) In permafrost under the surface of the lunar highlands
D) As subsurface deposits in maria,from water released by molten lava and trapped under solidified crust

Question 78

What characteristic of Jupiter's moon Io makes it different from any other known satellite in the solar system?

A) It has geyser-like plumes of nitrogen gas.
B) It is volcanically active.
C) It has a permanent,dense atmosphere that totally obscures the solid surface.
D) Its surface shows uncratered,flooded regions (now frozen)and other signs of geologically recent activity involving water.

Question 79

Which of the following Earth-bound phenomena do "volcanoes" on Io,the innermost Galilean moon of Jupiter,most resemble in behavior?

A) Undersea volcanoes,where hot lava produces explosive boiling of the water
B) Mountain volcanoes such as Mount St.Helens,exhibiting rare but devastating explosions that throw material high into the atmosphere
C) Lava-flow volcanoes occurring on the tops of mountains,such as those on Hawaii
D) Regularly spouting geysers in relatively flat hot-springs areas

Question 80

The major chemical constituent of the layers of material continuously being deposited on the surface of Io,a moon of Jupiter,by Io's eruptive plumes is

A) sulfur.
B) silicate dust and rock.
C) hydrogen.
D) water.