Deck 6: Home Base: Earth and Moon

Question 1

Which of the following is true of Earth's crust?

A) The ocean floor is much younger than the continental material.
B) It is divided into two major plates.
C) It is the thickest layer of Earth.
D) It has a composition most similar to the outer core.

Answer 1

The ocean floor is much younger than the continental material.

Question 2

How would the surface of Earth change if its deep interior had no radioactive elements?

A) There would be no plate tectonics.
B) It would be more hospitable to life.
C) It would have deeper oceans.
D) There would be no significant change.

Answer 2

There would be no plate tectonics.

Question 3

An atomic nucleus that transforms from one element to another has undergone:

A) ionization.
B) radioactive decay.
C) excitation.
D) scattering.

Answer 3

radioactive decay.

Question 4

The layer of Earth shown in the figure below is called the:

A) mantle.
B) inner core.
C) outer core.
D) subduction zone.

Question 5

The wave shown in the figure below is most similar to a(n):

A) seismic P-wave.
B) seismic S-wave.
C) electromagnetic wave.
D) gravitational wave.

Question 6

A long line of active volcanoes often marks:

A) a plume.
B) an area of increased radioactivity.
C) a weak point in the crust.
D) the boundary of two plates.

Question 7

Our understanding of Earth's interior comes primarily from:

A) deep drilling.
B) earthquakes.
C) magnetism.
D) volcanoes.

Question 8

Which of the following sequences correctly characterizes the composition of Earth's layers,from its center to its surface?

A) solid iron, molten iron, solid nickel, granite
B) silicate rocks, molten iron, silicate rocks
C) molten iron, silicate rocks, granite
D) solid iron, molten iron, silicate rocks

Question 9

Which moon in the Solar System has the largest mass relative to the planet it orbits?

A) Jupiter-Ganymede
B) Saturn-Titan
C) Earth-Moon
D) Neptune-Triton

Question 10

Which layers of Earth transport heat primarily through the bulk motion of material?

A) outer core only
B) inner core only
C) outer core and mantle
D) all layers

Question 11

The ultimate power source of plate tectonics comes from:

A) volcanoes.
B) radioactive decays.
C) convection.
D) friction.

Question 12

A meteor contains fifteen times as much argon-40 as potassium-40.If the half-life of potassium-40 is 1.25 billion years,how long ago did the meteor form?

A) 2.5 billion years
B) 3.75 billion years
C) 5 billion years
D) 6.25 billion years

Question 13

When a cup of coffee cools through rising and falling motions of the fluid,we say it undergoes:

A) plume formation.
B) radiation.
C) convection.
D) conduction.

Question 14

Which of the following is NOT a common result of the collision of two plates?

A) earthquakes
B) volcanoes
C) mid-ocean ridges
D) mountain ranges

Question 15

If Earth's Moon were less massive,which of the following would be most likely to occur?

A) Earth's climate would become less stable.
B) Earth would move to a wider orbit around the Sun.
C) Solar eclipses would be more common.
D) The Moon would spin faster.

Question 16

The Hawaiian Islands provide evidence for:

A) mantle plumes.
B) sea-floor spreading.
C) mantle convection.
D) all of the above.

Question 17

The refraction of P-waves in the mantle is due to:

A) the semimolten state of the mantle.
B) convection.
C) changes in the density.
D) radioactive decays.

Question 18

Uranium-238 undergoes radioactive decay with a half-life of 4.5 billion years,producing lead-206.After 13.5 billion years,what is the ratio of uranium-238 to lead-206 in a sample that originally contained only uranium-238?

A) 1:2
B) 1:3
C) 1:4
D) 1:8

Question 19

Suppose that a major earthquake occurs in southern California.A seismograph on the opposite side of Earth would see:

A) no signature.
B) P-waves but not S-waves.
C) P-waves but not S-waves
D) both P-waves and S-waves.

Question 20

A shield volcano is most likely to be associated with a(n):

A) earthquake-active zone.
B) plate boundary.
C) mantle plume.
D) subduction zone.

Question 21

Tides are caused by:

A) the centrifugal force of Earth's rotation.
B) surface gravity variations in the oceans.
C) the differential gravity of the Moon.
D) the differential gravity of the Moon and Sun.

Question 22

What is the most likely effect of the increased concentration of carbon dioxide in Earth's atmosphere since the 1800s?

A) increased surface temperatures
B) decreased ultraviolet radiation at Earth's surface
C) decreased ocean temperatures
D) increased atmospheric density

Question 23

A planet that experiences an increase in its atmospheric carbon dioxide concentration will also likely experience a(n):

A) increase in the thickness of its polar ice caps.
B) decrease in its surface temperature.
C) increase in its magnetic field.
D) decrease in the density of elements lighter than carbon dioxide in the atmosphere.

Question 24

If the greenhouse effect were to increase in importance,so that the temperature of Earth's atmosphere increased,then Earth's surface would radiate:

A) the same amount of energy into space as it does now.
B) more energy into space than it does now, with most of it in the visible.
C) more energy into space than it does now, with most of it in the infrared.
D) less energy into space than it does now.

Question 25

If the amount of ozone in the atmosphere decreased,which of the following would be most likely to occur?

A) Global surface temperatures would increase.
B) Seasonal changes would moderate.
C) The temperature inversion in the stratosphere would moderate.
D) The amount of ultraviolet radiation reaching Earth's surface would decrease.

Question 26

Which of the following is essential for a magnetic dynamo?

A) flows of charged particles
B) a solid bar magnet
C) rapid variations in the rotation rate
D) conduction

Question 27

Earth's magnetic field is created by:

A) the magnetized inner core.
B) iron deposits in the crust.
C) interactions with the solar wind.
D) currents in the outer core.

Question 28

The oxygen in Earth's atmosphere was first created 2.3 billion years ago by:

A) the impact of a massive comet.
B) photosynthesis.
C) the evaporation of water during a warming period.
D) solar radiation.

Question 29

Maria are:

A) captured moons of the gas giant planets.
B) massive volcanoes on Mars.
C) asteroids that trail in Jupiter's orbit.
D) dark areas on the lunar surface with relatively few craters.

Question 30

Tidal locking is responsible for:

A) the Sun's rotation period.
B) Earth's orbital period.
C) the Moon's rotation period.
D) the Venus-Mercury conjunction.

Question 31

The atmospheric layer in which most weather occurs is the:

A) troposphere.
B) mesosphere.
C) stratosphere.
D) ionosphere.

Question 32

Earth's original atmosphere escaped into space because:

A) Earth's gravity was weaker at the time.
B) it was ejected by comet and asteroid collisions.
C) it was chemically unstable.
D) it was composed of the lightest elements, hydrogen and helium.

Question 33

Which of the following is important for the greenhouse effect on Earth?

A) carbon dioxide
B) methane
C) water vapor
D) all of the above

Question 34

Aurorae are caused by:

A) the breakdown of the ozone layer.
B) scattered sunlight.
C) charged particles trapped by Earth's magnetic field.
D) atmospheric turbulence.

Question 35

Suppose a planet's atmosphere is composed of a mixture of elements and molecules.If the atmosphere's temperature increased,which of the following would be most likely to escape into space?

A) water
B) helium
C) ionized oxygen
D) ozone

Question 36

During a field reversal,Earth:

A) has a solid inner and outer iron core.
B) has a stronger bow shock.
C) experiences a greater flux of particles from the solar wind.
D) experiences more geologic activity than average.

Question 37

A planet is most likely to lose its atmosphere if it:

A) accretes more mass.
B) becomes geologically active.
C) heats up.
D) forms heavy molecules within its atmosphere.

Question 38

The most widely accepted theory for the formation of the Moon is the ________ hypothesis.

A) binary
B) capture
C) fission
D) impact

Question 39

Which of the following techniques has provided the most information to scientists studying the Moon's interior?

A) craters
B) seismology
C) satellite orbits
D) drilling

Question 40

"Snowball Earth" phases of geologic history were most likely caused by a(n):

A) decrease in the Sun's luminosity.
B) reduced concentration of atmospheric methane.
C) increased solar wind.
D) increase in volcanism.

Question 41

Spring tides occur:

A) during new and full moons.
B) during first quarter moons.
C) at the vernal equinox.
D) during new moons.

Question 42

Which of the following lunar features is NOT a direct result of impacts with comets or asteroids?

A) craters
B) rays
C) sinuous rills
D) terracing

Question 43

What kind of magnet does Earth's magnetic field most closely resemble?

Question 44

Lunar maria formed:

A) near the end of the Late Heavy Bombardment.
B) near the beginning of the Late Heavy Bombardment.
C) near the beginning of the Early Bombardment.
D) during the Moon's formation.

Question 45

The Moon formed primarily from:

A) a captured planetesimal.
B) Earth's mantle.
C) Earth's core.
D) the same mixture of material as Earth.

Question 46

Imagine that an earthquake occurs above a massive pool of molten lava.How would this pool affect the propagation of seismic waves?

Question 47

If the Moon's mass were larger,which of the following would be true?

A) Earth's rotation period would be longer.
B) Earth's rotation period would be shorter.
C) Earth's orbital period would be longer.
D) Earth's orbital period would be shorter.

Question 48

The figure below shows the layers of Earth's atmosphere,along with their temperature profiles labeled 1-4 from bottom to top.Name each of these layers,from Earth's surface upward.

Question 49

The figure below shows a diagram of Earth's interior.Name the layers shown here,and identify their principal compositions.

Question 50

The figure below shows the tidal bulge of Earth generated by the Moon.What will happen in the future as a result of this configuration?

A) Earth's tides will increase in amplitude.
B) Earth's days will become longer.
C) Earth's rotation axis will precess.
D) The Moon's orbit will slow down.

Question 51

The lack of potassium in lunar rocks supported the impact hypothesis because:

A) potassium is rare on asteroids.
B) it indicates the rocks were once at very high temperature.
C) potassium only exists in Earth's core.
D) any pre-existing potassium on the moon would have decayed during impact.

Question 52

Why are rocks on the ocean floors all younger than about 200 million years?

Question 53

Why is the Earth-Moon system unique compared to other planet-moon systems in the Solar System?

Question 54

The figure below shows the Earth-Moon system.At which of the marked locations do high tides occur?

A) 1
B) 1 and 3
C) 1 and 4
D) 2 and 4

Question 55

Half of the carbon-14 in a rock decays to nitrogen-14 after about 5,700 years.How long would it take before there is seven times as much carbon-14 as nitrogen-14 (i.e.the composition of the sample is 7/8 carbon-14)?

Question 56

Compared to primitive meteorites,the Moon's mantle is:

A) deficient in iron and enriched in silicates.
B) deficient in iron and silicates.
C) enriched in iron and silicates.
D) enriched in iron and deficient in silicates.

Question 57

How is the heat powering a shield volcano generated and transported?

Question 58

How do the interiors of Earth and the Moon differ?

A) The Moon has a mostly nickel core, while Earth's is mostly iron.
B) The Moon has a rigid mantle.
C) The Moon has a smaller iron core and thicker crust relative to its size.
D) all of the above

Question 59

According to plate tectonics,where do most earthquakes occur?

Question 60

Without an atmosphere,Earth's surface temperature would be below the freezing point of water.What is responsible for the heating that allows liquid oceans to form?

Question 61

What does the lack of a large-scale lunar magnetic field imply about the Moon's interior?

Question 62

Why has the surface temperature of Earth varied throughout geologic history?

Question 63

Why did Earth lose its primary atmosphere?

Question 64

A planet with the same radius as Earth is just barely able to retain oxygen in its atmosphere.Another planet with an identical temperature is twice as massive as the first.What is the maximum radius of the second planet if it is also to retain oxygen in its atmosphere?

Question 65

Suppose that Earth's magnetic poles were along the equator.How would that affect the aurorae,and why?

Question 66

What kind of tides occur during a lunar eclipse? How do they compare to the average amplitude of tides averaged over a month?

Question 67

The fission hypothesis states that the Moon formed when rotation pulled material away from the molten Earth.What is the primary objection to this scenario?

Question 68

What is responsible for heating the stratosphere? What about the ionosphere?

Question 69

Why is the Moon's rotation period equal to its orbital period?

Question 70

What can you conclude about a large region of the Moon's surface with relatively few craters?