ESC Midterm Flashcards

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1
Q

A government report about a hurricane would

A

be part of the discipline of meteorology.

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2
Q

A newspaper article about an earthquake would be reporting on the discipline of

A

geology.

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3
Q

According to the figure, the birth of the Earth occurred approximately

A

4,540 Ma.

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4
Q

Glaciers would be considered part of both the cryosphere and the

A

hydrosphere.

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5
Q

If buying a house in the area shown, Earth Science may help you determine

A

if the area is safe from natural hazards.

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6
Q

The difference between meteorology and climate science is that

A

meteorology studies shorter-term conditions of the atmosphere and climate science studies the longer-term trends.

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7
Q

The mantle and core would be considered part of which Earth System realm?

A

Geosphere

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8
Q

The study of Earth’s oceans and their interaction with Earth’s land and atmosphere is called

A

oceanography

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9
Q

The theory of _________ is considered to be the foundation of geology.

A

plate tectonics

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10
Q

Which one of these practical questions may be answered by Earth Science?

A

What will the weather be like today?

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11
Q

A bathymetric map of the Earth’s oceans would reveal that most of the ocean floor is made up of

A

abyssal plains.

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12
Q

Earth’s core

A

generates Earth’s magnetic field.

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13
Q

Edwin Hubble’s research was important because

A

his measurements of galaxies showed that the Universe is expanding.

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14
Q

From earliest to latest, which of the following is the correct order of events in the formation of Earth?

A

Formation of accretionary disk, formation of planetesimals, differentiation, formation of Moon

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15
Q

How did the Earth become round?

A

The early Earth’s interior rock became warm enough to flow in response to gravity.

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16
Q

Scientific cosmology

A

investigates the overall structure and history of the Universe.

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17
Q

Soil forms when ________ interact(s) with air, water, and organisms.

A

sediment

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18
Q

The Big Bang

A

began with all matter and energy concentrated in an infinitesimally small point.

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19
Q

The Moho is the boundary between Earth’s

A

crust and mantle.

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20
Q

The earliest nebulae to form in the Universe were made almost entirely of

A

hydrogen and helium.

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21
Q

The geothermal gradient

A

refers to the rate of increase in temperature with increasing depth in the Earth.

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22
Q

The leading hypothesis for the formation of our Moon states that it

A

was formed by the collision of Earth with a Mars-sized protoplanet.

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23
Q

The nebular theory explains

A

how the Solar System formed.

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24
Q

The process by which the Earth developed its layered interior is called

A

differentiation.

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25
Q

The two most common gases of Earth’s atmosphere are

A

nitrogen (N2) and oxygen (O2).

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26
Q

The type of rock formed by the solidification of molten rock is

A

igneous.

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27
Q

This figure shows the planets of the Solar System and their positions relative to the Sun. Rocky planets are closest to the Sun, and the gas and ice giants are farther away. Which of the following sequences places the planets in the correct order?

A

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

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28
Q

This figure shows the planets of the Solar System and their positions relative to the Sun. Which observation about the planets’ arrangement is true?

A

The asteroid belt marks the boundary between the rocky planets and the gas giants.

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29
Q

Using this image, describe the relationship between air pressure and altitude.

A

At the top of Mt. Everest, air pressure is less than 0.4 bars.

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30
Q

Which layer of the Earth’s interior is completely molten?

A

Outer core

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31
Q

Which of Earth’s layers accounts for most of the volume of Earth?

A

Mantle

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32
Q

Which of Earth’s layers is the thinnest?

A

Crust

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33
Q

Which of the following groups of elements make up most of the mass of the Earth?

A

Iron, oxygen, silicon, and magnesium

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34
Q

Which of the following serves as a trap for cosmic rays and shields life on Earth from excessive radiation?

A

Van Allen belts

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35
Q

Which of these is a terrestrial planet?

A

Mars

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36
Q

A subducting (or downgoing) plate

A

will have a trench associated with it.

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37
Q

According to the mantle plume model for the origin of hot spots

A

mantle plumes produce volcanoes that do not always coincide with a plate boundary.

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38
Q

Accretionary prisms form as a result of what process?

A

Subduction

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39
Q

Asthenosphere

A

is warm enough to flow slowly.

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40
Q

By using GPS data, scientists have been able to

A

directly observe plate motions.

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41
Q

During the process of seafloor spreading

A

new seafloor is formed at ridges and destroyed at trenches.

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42
Q

Earth’s magnetic field is created primarily by the

A

flow of liquid iron alloy in Earth’s molten outer core.

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43
Q

East Africa and the Basin and the Range Province of the United States are examples of a

A

continental rift.

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44
Q

Identify the plate boundary in the image.

A

convergent

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45
Q

Identify the plate boundary in the image.

A

transform

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46
Q

In the figure the magnetic anomaly pattern is mirrored on either side of the central ridge. What is responsible for this pattern?

A

Reversals of the direction of Earth’s magnetic field occur during seafloor spreading.

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47
Q

Oceanic crust

A

is composed of basalt and lies under a blanket of sediment.

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48
Q

Plate tectonics theory took decades to be accepted because

A

Wegener couldn’t explain how continents moved.

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49
Q

Plate tectonics theory was widely accepted by scientists in what decade?

A

1960s

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50
Q

The Hawaiian Islands, a chain of volcanic islands located in the middle of the Pacific Plate, extend northwest across the Pacific as shown in the figure. The island of Hawaii is the youngest, and the islands get progressively older to the northwest. How are the positions of the islands explained by plate tectonic theory?

A

A hot spot is currently situated under Hawaii and the Pacific Plate is moving across it in a northwesterly direction.

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51
Q

The Himalayas are currently growing because at their location

A

a continental plate is colliding with another continental plate.

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52
Q

The center of a mid-ocean ridge is where

A

new oceanic lithosphere is being created.

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53
Q

The chain of volcanoes along the west coast of South America (the Andes Mountains) exists because

A

an oceanic plate is subducting under the western edge of the South American Plate.

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54
Q

The contact between lithospheric plates is called a

A

plate boundary.

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55
Q

The global occurrence of earthquakes reveals that

A

they usually occur on the boundaries of plates.

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56
Q

The rate of plate motion

A

can range from 1 to 15 cm per year.

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57
Q

Which of the following has faulting but no volcanic activity?

A

Transform plate boundary

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58
Q

Which of the following statements about lithosphere and asthenosphere is TRUE?

A

Lithosphere consists of the crust and the upper mantle, and behaves like a hard layer that breaks and bends.

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59
Q

Which of the following was used as evidence by Wegener to develop the theory of continental drift?

A

The presence of matching mountain chains on continents currently separated by oceans

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60
Q

Why is the lithosphere rigid while the asthenosphere is not?

A

The temperature in the asthenosphere is higher than the lithosphere so the rock is softer.

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61
Q

According to Mohs hardness scale

A

gypsum is softer than fluorite.

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62
Q

Asbestos was widely used as a fireproofing insulation. Why is it no longer used?

A

When inhaled it can embed in the lungs and cause cancer.

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63
Q

Calcite and aragonite minerals that constitute clamshells are examples of which method of mineral formation?

A

Biomineralization

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64
Q

Crystalline rocks

A

are rocks whose grains grew to interlock.

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65
Q

Diamonds are very hard gemstones that form

A

when graphite is subjected to high pressure.

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66
Q

Glass is not considered a mineral because

A

it does not have a crystal structure.

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67
Q

Most of the major chemical classes of minerals are defined by which chemical group that the mineral contains?

A

Negatively charged ion or group

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68
Q

Rocks in which individual mineral grains are held together by a cement are

A

clastic rocks.

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69
Q

Rocks that form at or near Earth’s surface by the cementing of grains or precipitation from water are

A

sedimentary.

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70
Q

The building block of the silicate minerals is called the

A

silicon-oxygen tetrahedron.

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71
Q

The image shows a calcite fragment. The calcite has

A

three planes of cleavage, one of which is inclined.

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72
Q

The migration of atoms or molecules through a material is called

A

diffusion.

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73
Q

The mineral crystals of amethyst growing into the center of the geode in the figure are

A

euhedral.

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74
Q

The most abundant mineral group on Earth is the

A

silicates.

75
Q

The quartz in this figure shows a very specific type of breakage. What is this type of break called?

A

Conchoidal fracture

76
Q

The tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces is called

A

conchoidal fracture.

77
Q

The type of rock that forms by solidification of molten rock is

A

igneous.

78
Q

This figure shows a sample of pyrite (FeS2). Which of the following statements can be determined to be true simply by visual inspection of this sample?

A

Pyrite has metallic luster and a cubic crystal habit.

79
Q

What physical property of a mineral describes the shape of a cluster of many well-formed crystals that grew together as a group?

A

Habit

80
Q

When a mineral specimen is scraped along a ceramic plate to observe the color of its powder, the physical property being checked is

A

streak.

81
Q

Which of the following is a mineral?

A

Salt (NaCl)

82
Q

Which of the following would be best used to study rocks in the field?

A

Hand lens

83
Q

Which type(s) of rock(s) may display layering?

A

Sedimentary and metamorphic

84
Q

Why would brick not be considered a rock?

A

Bricks are manmade.

85
Q

___________ rocks form when existing rocks are subjected to high temperatures and pressures that cause changes in mineralogy and texture but do not melt.

A

Metamorphic

86
Q

A felsic or silicic magma

A

is more viscous than mafic magma.

87
Q

A moving, glowing, descending cloud of hot gases and volcanic pieces

A

is called a pyroclastic flow or nuée ardente.

88
Q

According to Bowen’s reaction series, as a magma cools in the discontinuous series, minerals will crystallize in which order?

A

Olivine, pyroxene, amphibole, biotite

89
Q

Bowen’s reaction series

A

was established by laboratory experiments in the 1920s.

90
Q

Lahars, composed of ash, pyroclastic debris, and water,

A

have often resulted in damage and death to humans and their property.

91
Q

Magma may cool and crystallize to become solid igneous rock

A

very slowly (in centuries to a million years) when it forms a deep pluton.

92
Q

Magmas have a variety of chemical compositions because

A

they can incorporate chemicals from the surrounding rock.

93
Q

Obsidian is classified as having a __________ texture.

A

glassy

94
Q

The difference between a dike and a sill is that

A

a dike cuts across pre-existing layers while a sill is parallel to them.

95
Q

The dramatic scenery of the Sierra Nevada Mountains in California, shown here,

A

owes its existence to erosion of a batholith.

96
Q

The magma with the highest percentage of iron oxide and magnesium oxide and lowest percentage of silica is

A

ultramafic.

97
Q

The presence of pillow lava is evidence of

A

a submarine eruption.

98
Q

This image shows a classic example of

A

columnar jointing.

99
Q

This stratovolcano erupted in 1980 in the United States. Although there were warnings of its impending eruption, it still killed dozens, partly because it first blew sideways, producing a monstrous landslide. This volcano is

A

Mt. St. Helens.

100
Q

Using the diagram, identify the coarse-grained igneous rock with abundant plagioclase and lesser amounts of quartz, pyroxene, amphibole, and biotite.

A

Diorite

101
Q

Volcanic eruptions vary in size from very small to extremely large events. This image shows the different stages of a cataclysmic eruption. What type of eruption is shown by this sequence of images?

A

Caldera eruption

102
Q

Which describes the melting that takes place when deep hot rock rises to shallower depths without cooling?

A

Decompression melting

103
Q

Which eruption or volcano type is likely to produce the most violently ejected pyroclastic fragments?

A

Stratovolcano

104
Q

Which explosive volcano erupted in 1815, resulting in temperatures so cool that the following year was called “the year without a summer”?

A

Mt. Tambora in Indonesia

105
Q

Which of the following describes an elongated crack that may serve as a conduit for lava to erupt on the surface?

A

Fissure

106
Q

Which of the following is associated with intrusive igneous activity?

A

Crystallization of magma underground

107
Q

Which of the following is considered a warning sign of imminent eruption?

A

earthquake activity

108
Q

Which of the following volcanic areas is part of the Ring of Fire?

A

Mt. Pinatubo, Philippines

109
Q

Why does magma tend to rise upward once it forms?

A

The magma is less dense than the surrounding rock.

110
Q

A thick soil profile indicates that

A

the soil likely formed over a long period of time.

111
Q

A very fine-grained clastic sedimentary rock is called a

A

shale.

112
Q

Coal is an example of which type of sedimentary rock?

A

Organic

113
Q

Coral reefs that are preserved as sedimentary rocks are classified as

A

limestones.

114
Q

Finely laminated shale was likely formed from sediments deposited

A

in a lake.

115
Q

Geologists find a series of graded beds, one on top of another. What events could have produced this set of structures?

A

Repeated turbidity currents

116
Q

How were thick layers of halite and gypsum deposited beneath the Mediterranean Sea?

A

At times of low global sea level, the Mediterranean Sea was cut off from the Atlantic Ocean, and the trapped seawater evaporated.

117
Q

In the environment shown, the waves sort the beach sediments. What type of clastic sedimentary rock is most likely to form in this environment?

A

Sandstone

118
Q

Layers of sedimentary rocks are called

A

beds.

119
Q

Limestone that forms by inorganic chemical precipitation is

A

travertine.

120
Q

More mature sediments are typically

A

further from their source and better sorted.

121
Q

Natural, smaller-scale cracks in a rock that form as deeply buried crust rises to the Earth’s surface are called

A

joints.

122
Q

Reactions of iron-bearing minerals with Earth’s atmosphere result in a type of chemical weathering called

A

oxidation.

123
Q

The accumulation of decaying organic material near the top of a soil is called

A

humus.

124
Q

The figure shows several different magnified samples of sediments. Which of the samples displays the BEST sorting?

A

D

125
Q

The soil shown in the figure has no O-horizon and has a B-horizon with abundant calcite deposits called calcrete. This type of soil is most likely to form in

A

deserts.

126
Q

The transformation of loose sediment into solid rock is a process called

A

lithification.

127
Q

What type of clastic sedimentary rock will form in the environment shown?

A

Conglomerate

128
Q

What type of environment likely created the bedding structure shown?

A

Desert with migrating dunes

129
Q

When relative sea level rises, the shoreline migrates inland in a process called

A

transgression.

130
Q

Where is a sedimentary basin likely to be found?

A

Continental rift

131
Q

Which chemical reaction breaks down feldspars into clay minerals?

A

Hydrolysis

132
Q

Which of the following would be considered sediment?

A

Clam shells on a beach

133
Q

Which of the four main classes of sedimentary rock forms by the precipitation of minerals directly from water, without help from living organisms?

A

Chemical

134
Q

Which soil horizon consists of weathered bedrock material that has not yet been leached or had significant accumulation?

A

C

135
Q

A rock experienced melting then cooling, burial to deep depths during mountain building, and then uplift and weathering. Which pathway did this rock take through the rock cycle?

A

Igneous → metamorphic → sedimentary

136
Q

As they pass through the rock cycle, all atoms

A

do not move through the rock cycle at the same rate.

137
Q

Different temperature and pressure ranges create specific sets of metamorphic minerals that are called metamorphic facies. Using the graph, determine what facies a rock would be found in if it was buried 30 km deep and heated to a temperature of approximately 200 degrees C.

A

Blueschist

138
Q

During metamorphism, the process that changes the crystal structure of a mineral without changing its chemical composition is called

A

phase change.

139
Q

Identify the metamorphic process that causes grains to warp and/or elongate but not melt or dissolve.

A

Plastic deformation

140
Q

Identify the metamorphic process that is shown in the image.

A

Pressure solution

141
Q

Identify the metamorphic process that is shown in the image.

A

Recrystallization

142
Q

In a rock undergoing metamorphosis, which type of stress occurs when one part of a rock moves sideways relative to the rest of the rock?

A

Shear stress

143
Q

Metamorphic grade is determined mainly by

A

temperature.

144
Q

Metamorphic rocks differ from igneous rocks in their formation because metamorphic rocks

A

do not form from molten rock.

145
Q

Metamorphism can occur in the surrounding rock as an igneous pluton forms. Which type of metamorphism is most likely to occur in the surrounding rock?

A

Thermal or contact metamorphism

146
Q

Shale, a sedimentary rock, can be subjected to high heat and pressure through

A

burial during continental collision.

147
Q

The fine-grained foliated metamorphic rock formed from the metamorphism of shale or mudstone is called

A

slate.

148
Q

The temperature range for the formation of low-grade metamorphic rocks is __________ degrees C.

A

250 to 400

149
Q

The various geologic environments of the rock cycle (in which rocks can melt, metamorphose, or become sediment) are ultimately generated by

A

plate tectonics.

150
Q

Using the graph, determine what type of metamorphism (related to its geologic setting) a rock would likely be experiencing if it was at a depth of 20 km and heated to a temperature of 500 degrees C.

A

Mountain belt metamorphism

151
Q

What type of metamorphism would occur at a plate boundary where two continents are colliding?

A

Dynamothermal or regional metamorphism

152
Q

When a rock is subjected to compressional pressure, the grains will

A

elongate perpendicular to the direction of stress.

153
Q

Which agent of metamorphism involves hot water moving ions?

A

Interaction with hydrothermal fluids

154
Q

Which nonfoliated metamorphic rock forms from the metamorphism of limestone?

A

Marble

155
Q

Which of the following describes an igneous to metamorphic to sedimentary path through the rock cycle?

A

A granite becomes buried and heated to form gneiss, and is then uplifted and eroded to make sand.

156
Q

Which process brings metamorphic rocks to the surface over time?

A

Exhumation

157
Q

Which statement about the pathways of the rock cycle is TRUE?

A

Granite that is eroded, transported, deposited, and lithified will become a sedimentary rock.

158
Q

Which type of foliation does gneiss have?

A

Compositional layering

159
Q

A fold-thrust-belt is associated with

A

subduction.

160
Q

A horizontal line on Earth’s surface has a plunge of

A

161
Q

A series of anticlines and synclines forms as a result of

A

compression.

162
Q

According to the principle of isostasy, tall mountains

A

have deep roots.

163
Q

Brittle deformation

A

occurs when many atomic bonds are broken quickly and rock pieces separate.

164
Q

Continental lithosphere that has not experienced a mountain-building event in at least one billion years is called a(n)

A

craton.

165
Q

Depending on the direction of force (red arrows in the diagrams), stress is categorized as compression, tension, shear, or pressure. Which of the following diagrams shows tension?

A

B

166
Q

Identify the structure in the image.

A

Syncline

167
Q

If you see small, angular fragments of shattered rock along a linear boundary between two masses of rock, you are looking at

A

fault breccia.

168
Q

Igneous rock can form during mountain building when

A

flux melting occurs at convergent boundaries.

169
Q

Mountain building at convergent margins produces several distinct geologic settings. This diagram represents an orogeny in which one continent has already collided with another continent. Where on the image is a suture located?

A

C

170
Q

Stress

A

generated during orogeny can be different at various locations.

171
Q

The Andes Mountains are an example of mountains formed by

A

subduction.

172
Q

The Himalayas formed by

A

collision.

173
Q

The North American craton consists of a

A

shield and platform.

174
Q

The crust in the Basin and Range Province of Nevada, Utah, and Arizona is stretching; therefore, fault movement in this region must be

A

normal.

175
Q

The process of mountain belt formation is called

A

orogeny.

176
Q

The structure pictured in the diagram is a(n)

A

basin.

177
Q

What is the change in shape produced by stress called?

A

Strain

178
Q

What type of fault does the diagram show?

A

Dip-slip fault, normal

179
Q

What type of fault does the diagram show?

A

Left-lateral strike-slip fault

180
Q

Where would metamorphic rocks form during mountain building?

A

Near plutons

181
Q

Which of the following conditions will tend to make rocks change by plastic deformation rather than by brittle deformation?

A

Slowly applied stress

182
Q

Which process can cause mountains to erode and decrease in elevation?

A

Movement of glaciers

183
Q

You’re looking at a fault trace in the field. You observe a polished surface with linear grooves on it, and fine powder next to it. In more technical terms, what are you seeing?

A

Slickensides, slip lineations, and fault gouge