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Study Guide

Sample Selected-Response Questions
Field 45: Earth Science

Practice Questions

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Subarea I–Characteristics of Science

Objective 0001: Understand the historical and contemporary contexts of the study of Earth and space science.

1. In the eleventh century, the Arabic scholar Avicenna proposed that mountains could only have formed over long periods of time. He based this hypothesis on his knowledge of geologic processes that he had observed, such as water erosion and the localized uplift caused by earthquakes. In applying his knowledge of geologic processes that he had observed firsthand to understand the geologic past, Avicenna was employing which of the following geologic principles fundamental to modern geology?

  1. original horizontality
  2. superposition
  3. cross-cutting relationships
  4. uniformitarianism
Enter to expand or collapse answer. Answer expanded
Correct Response: D.
Objective 0003: Understand the principles and procedures of scientific investigations.

2. In a 20-year project, a team of scientists sets up multiple strainmeters on either side of an active strike-slip fault to determine how the bedrock deforms prior to minor earthquakes. The collected deformation data is correlated with seismograms for the area from the same period. The correlation of the two data sets will help the scientists determine if there are patterns in the deformation data that consistently precede minor earthquakes on the fault. In this experiment, which of the following factors is the dependent variable?

  1. the movement of the land surface during minor earthquakes
  2. the types of seismic waves generated during minor earthquakes
  3. the deformation of the bedrock prior to minor earthquakes
  4. the frequency of fault activity resulting in minor earthquakes
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0004: Understand the processes of gathering, organizing, reporting, and analyzing scientific data in the context of Earth and space science investigations.

3. Which of the following events would be least likely to occur at a significantly smaller scale?

  1. The erosion of a hillside produces sediment that is washed into a stream.
  2. An interstellar dust cloud forms a star as a result of gravitational attraction.
  3. The discharge of static electricity during a storm produces a lightning bolt.
  4. A magnetic field is generated by electric currents in the Earth's outer core.
Enter to expand or collapse answer. Answer expanded
Correct Response: B.
Objective 0005: Understand how Earth and space science interrelates with society, technology, and the other sciences and applies to everyday life.

4. Analysis of the ratio of the oxygen isotopes 18O and 16O has been extremely useful in which of the following areas of Earth and space science research?

  1. calculating the age of lava flows from Pleistocene era volcanic eruptions
  2. determining relative changes in global temperature during the Quaternary period
  3. calculating the concentration of carbon dioxide in gas bubbles trapped in ice sheets
  4. determining sedimentation rates on the abyssal plains of the deep oceans
Enter to expand or collapse answer. Answer expanded
Correct Response: B.

 

Subarea II–Origin and Evolution of the Earth System

Objective 0006: Understand the formation and structure of the Earth and the role of internal and external energy in the Earth's formation.

5. Radiometric dating of which of the following materials has provided an estimate for the earliest date at which the Earth could have formed?

  1. ultramafic rocks from deep below the Earth's surface
  2. Precambrian rocks from the Canadian Shield
  3. banded iron formations from ancient sedimentary rocks
  4. meteorites collected from the Earth's surface
Enter to expand or collapse answer. Answer expanded
Correct Response: D.
Objective 0007: Understand plate tectonics and the internal dynamics that drive plate movements.

6. Which of the following geologic processes is responsible for the formation of the horst and graben structures of the Basin and Range Province of the western United States?

  1. differential erosion of volcanic rocks and sedimentary rocks over several million years
  2. tensional forces that produced crustal extension of this section of the North American Plate
  3. cycles of erosion and deposition associated with the multiple glaciations of the Pleistocene
  4. compressional forces that generated uplift of this section of the North American Plate
Enter to expand or collapse answer. Answer expanded
Correct Response: B.
Objective 0008: Understand the Earth's history, the geologic time scale, and the theory and application of relative and absolute dating techniques.

7. Scientists believe that the rapid evolution and diversification of species that occurred at the beginning of the Mesozoic era was to a great extent a consequence of:

  1. the breakup of the supercontinent Pangaea in the Late Paleozoic period.
  2. changes in atmospheric composition resulting from the appearance of photosynthetic organisms.
  3. the extinction of the majority of species near the end of the Permian period.
  4. changes in the rate of genetic mutations resulting from the Sun's increased output of harmful radiation.
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0009: Understand the processes that create and change landforms.

8. In the Sierra Nevada mountain range of California, many of the large mountain tops are exposed granitic batholiths that have eroded into rounded domes, known as exfoliation domes. Which of the following processes is specifically involved in the formation of these exfoliation domes?

  1. sheeting of large concentric slabs from pressure unloading
  2. chemical weathering of potassium ions on the rock surface
  3. erosion of granite during periods of high runoff
  4. fluctuating temperatures that shrink and swell the rock face
Enter to expand or collapse answer. Answer expanded
Correct Response: A.

 

Subarea III–Geologic Materials, Processes, and Cycles

Objective 0011: Understand minerals and rocks, their formation, and their identification.

9. Pegmatites are intrusive igneous rocks composed of unusually large crystals. Geologists believe that pegmatites typically form under which of the following conditions?

  1. at the bottom of the solidifying magma bodies below extinct volcanoes
  2. at very slow rates of crystallization and high temperatures near the mantle-crust boundary
  3. in the fluid-rich residual melt left over after most of a granitic batholith has solidified
  4. at relatively fast rates of crystallization as magma flows rapidly away from its source to form a sill
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0013: Understand earthquakes.

10. A structure built on which of the following types of geologic materials would typically experience the most damage from shaking caused by a major earthquake?

  1. heavily fractured shale
  2. karstic limestone
  3. unconsolidated silt and clay
  4. massive granite
Enter to expand or collapse answer. Answer expanded
Correct Response: C.

MULTIPLE-SUBAREA PASSAGE

Use the information below to answer the two questions that follow.

There is a diagram with the title Fractional Crystallization in the Differentiation of a Granitic Magma.

Four stages are shown, each in a square frame, labeled from left to right as Stage 1 through Stage 4. Below the stages is an arrow labeled Cooling of Magma, pointing from left to right, marked 1200° Celsius at the left end and 650° Celsius at the right end. Below the arrow is a key indicating that the gray background color in each frame is melt remaining as crystals form. Stage 1 shows long, narrow trapezoidal shapes accumulating at the bottom of the frame. Stage 2 shows the first set of shapes compressed at the bottom of the frame, with small square shapes accumulating on top of them. Stage 3 shows the first set of shapes at the bottom, the second set compressed on top of them, and long, narrow rectangular shapes accumulating on top of them. Stage 4 shows the first set of shapes at the bottom, the second set compressed on top of them, the third set compressed on top of them, and small- five-sided shapes accumulating on top of them.

Objective 0012: Understand volcanoes and other types of igneous activity.

11. During the process of magmatic differentiation shown in the graphic, which of the following minerals is most likely to crystallize from the magma in stage 1?

  1. quartz
  2. potassium feldspar
  3. olivine
  4. muscovite mica
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0014: Understand geochemical cycles.

12. Relative to the other stages, the melt remaining in stage 4 would most likely be enriched in which of the following substances?

  1. iron
  2. plagioclase feldspars
  3. calcium
  4. metallic ions
Enter to expand or collapse answer. Answer expanded
Correct Response: D.

 

Subarea IV–The Hydrosphere and the Atmosphere

Objective 0015: Understand freshwater systems.

13. Use the diagram below to answer the question that follows.

There is a diagram of four well logs, labeled with the locations where the logs were made.

To the right of the well logs is a scale, labeled Depth below Surface, marked with values from 0 to 100 feet in increments of 25. Each log shows a column of soil material layers, identified by a key, together with a water table surface symbol, also identified by the key. All following values are approximate.
From the surface down, Well Log from Location A indicates sand and gravel to a depth of 25 feet, fine sand and silt from there to a depth of 40 feet, limestone from there to a depth of 65 feet, and shale from there to a depth of 100 feet. The water table is marked at 15 feet.
Well Log from Location B indicates fine sand and silt to a depth of 12 feet, coarse sand from there to a depth of 37 feet, sand and gravel from there to a depth of 85 feet, and limestone from there to a depth of 100 feet. The water table is marked at 20 feet.
Well Log from Location C indicates coarse sand to a depth of 25 feet, clay from there to a depth of 50 feet, basalt from there to a depth of 87 feet, and granite from there to a depth of 100 feet. The water table is marked at 11 feet.
Well Log from Location D indicates fine sand and silt to a depth of 25 feet, limestone from there to a depth of 60 feet, shale from there to a depth of 85 feet, and granite from there to a depth of 100 feet. The water table is marked at 22 feet.

The diagram shows four well logs from different locations in a valley. The wells were drilled as test wells to determine the best location for a municipal drinking-water well for a nearby town. Presuming water quality is similar in each test well, which of the following locations will most likely provide the best source of drinking water?

  1. Location A
  2. Location B
  3. Location C
  4. Location D
Enter to expand or collapse answer. Answer expanded
Correct Response: B.
Objective 0016: Understand the structure and composition of different layers in the atmosphere and atmospheric processes.

14. Changes to the Earth's climate system resulting from the 1991 eruption of Mount Pinatubo in the Philippines were primarily caused by:

  1. sulfur dioxide that was ejected into the lower stratosphere.
  2. particulates that became trapped in the upper troposphere.
  3. carbon dioxide that was ejected into the upper stratosphere.
  4. nitrogen oxide that increased smog in the lower troposphere.
Enter to expand or collapse answer. Answer expanded
Correct Response: A.
Objective 0017: Understand the Earth's climate system.

15. Wind flow aloft is typically parallel to atmospheric pressure isobars, while winds at the Earth's surface typically cross the isobars that separate a high-pressure center from a low-pressure center. This difference between wind flow aloft and at the Earth's surface is primarily caused by:

  1. increased frictional drag on wind flow at the Earth's surface.
  2. reduced strength of the Coriolis effect on wind flow aloft.
  3. greater divergence of winds above a low-pressure system.
  4. decreased atmospheric pressure with increased altitude.
Enter to expand or collapse answer. Answer expanded
Correct Response: A.
Objective 0018: Understand weather and weather prediction.

16. Which of the following conditions must be met for a low-pressure system to continue to develop into a stronger low-pressure system?

  1. divergent wind flow at the base of the low-pressure system
  2. cold-air advection above the low-pressure system
  3. convection of relatively warm air within the low-pressure system
  4. convergent wind flow above the low-pressure system
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0019: Understand the characteristics of ocean water, currents, and waves.

17. Chesapeake Bay on the eastern coast of the United States was one of the first locations where a hypoxic dead zone was identified in a marine habitat. Which of the following factors has been identified as the major contributor to the development of this hypoxic dead zone?

  1. runoff of nutrient-rich water into the bay from large-scale farming operations
  2. acidification of bay waters from an increased concentration of dissolved carbon dioxide
  3. warming of bay waters caused by the increase in average global temperatures
  4. accumulation in bay sediments of heavy metals produced by industrial manufacturing
Enter to expand or collapse answer. Answer expanded
Correct Response: A.

Subarea V–Astronomy

Objective 0020: Understand the characteristics and interactions of the Earth-Moon-Sun system.

18. The dark side of the Moon is never visible from the Earth's surface because:

  1. the Moon's rotational period matches the Earth's rotational period.
  2. the Moon's orbital period matches the Earth's orbital period.
  3. the Moon rotates on its axis once every time it orbits the Earth.
  4. the Moon completes one lunar orbit for every full day on the Earth.
Enter to expand or collapse answer. Answer expanded
Correct Response: C.
Objective 0021: Understand the characteristics and formation of the solar system.

19. Use the information below to answer the question that follows.

The diagram shows a planetary orbit around a sun, with the planet located at an arbitrary point on the orbit.

The orbit is elliptical with the sun at one focus of the ellipse. Area X is symmetrical around the end of the long axis of the ellipse where the sun is close to the ellipse, and area Y is symmetrical around the other end of the long axis. Area X is defined by 2 short radii and a long distance of arc on the perimeter of the ellipse, while Area Y is defined by 2 long radii and a short distance of arc on the perimeter of the ellipse.

In the diagram of a planet's orbit of the Sun, area X is equal to area Y. According to Kepler's second law, the equivalence of these two areas indicates that when the planet is closer to the Sun, the planet's:

  1. orbital speed increases.
  2. rotational speed increases.
  3. gravitational force decreases.
  4. linear momentum decreases.
Enter to expand or collapse answer. Answer expanded
Correct Response: A.
Objective 0023: Understand theories of the origin and evolution of the universe.

20. In developing Hubble's law, which of the following types of evidence did Edwin Hubble use to determine the recessional velocities of galaxies?

  1. the spectral redshift of the electromagnetic energy emitted by the galaxies
  2. the calculated age of the galaxies
  3. the change in the observed parallax of the local group of galaxies over several years
  4. the observed shape of the galaxies
Enter to expand or collapse answer. Answer expanded
Correct Response: A.