Chapter 10 HW

Put events in order from oldest to youngest. a. Compressional forces cause the sedimentary rocks to bend into an anticline. b. Sediments are deposited in a horizontal orientation. c. The sediments are buried and lithified into sedimentary rock. d. Processes of weathering and erosion expose the interior of the anticline.

1. Sediments are deposited in a horizontal orientation (b). 2. The sediments are buried and lithified into sedimentary rock (c). 3. Compressional forces cause the sedimentary rocks to bend into an anticline (a). 4. Processes of weathering and erosion expose the interior of the anticline (d).

If strike and dips symbols were placed on a map of a basin, which way would the dips point? a. Dips point down toward the center. b. Dips point up toward the center. c. Layers do not dip. d. Dips point down in the same direction, but at different angles. e. Dips point down away from the center.

a. Dips point down toward the center.

True or False? a. The sedimentary rock shown here has been significantly displaced. b. The cracks in the sedimentary rocks are joints. c. No cracks exist in this outcrop. d. The fractures are a result of brittle deformation.

a. False b. True c. False d. True

Imagine a fold has been eroded to a flat surface. In general, how would you know whether this fold is plunging? a. Nonplunging folds look like straight lines at the surface, and plunging folds look like wavy lines. b. Nonplunging folds look like wavy lines at the surface, and plunging folds look like straight lines. c. Nonplunging folds look like valleys at the surface, and plunging folds look like hills. d. Nonplunging folds look like hills at the surface, and plunging folds look like valleys.

a. Nonplunging folds look like straight lines at the surface, and plunging folds look like wavy lines.

Which of the following statements best describes the orientation of rock layers for a structural dome or structural basin? a. Rock layers wrap around a single point. b. Rock layers are horizontal and separated by a slight incline. c. Rock layers fold over a line.

a. Rock layers wrap around a single point.

Imagine a syncline has been eroded to a flat surface. How would the rock age change as you walked across that flat surface? a. Rocks would be oldest on the edges and youngest in the middle. b. Rocks would be youngest on the right and oldest on the left. c. Rocks would be youngest on the edges and oldest in the middle. d. Rocks would be youngest on the left and oldest on the right.

a. Rocks would be oldest on the edges and youngest in the middle.

Which type of force is responsible for reverse fault formation? a. compressional force b. tensional force c. shear force

a. compressional force

Which of the following is an example of how rocks will respond to compressional stress (2)? a. folding b. elongation c. reverse faulting d. transform faulting e. normal faulting

a. folding c. reverse faulting

Which type of force is responsible for normal strike-slip formation? a. shear force b. tensional force c. compressional force

a. shear force

Which statement(s) correctly describe(s) brittle deformation and ductile deformation (2)? a. Both types of deformation are reversible. b. Brittle deformation describes a rock breaking as a result of stress, whereas ductile deformation describes a rock bending or folding as a result of stress. c. Brittle deformation describes a rock bending or folding as a result of stress, whereas ductile deformation describes a rock breaking as a result of stress. d. Both types of deformation are permanent. e. Brittle deformation is permanent, whereas ductile deformation is reversible.

b. Brittle deformation describes a rock breaking as a result of stress, whereas ductile deformation describes a rock bending or folding as a result of stress. d. Both types of deformation are permanent.

Alluvial fans are composed of material built up from sediment from the foot of the mountains to the valley floor. They are evidence that __________. a. Death Valley is being compressed and the basins are rising b. Death Valley is a tectonically active region c. Death Valley receives vast amounts of rainfall d. the mountains in Death Valley are entirely composed of loose, unconsolidated sediment e. large rivers are responsible for sculpting the topography of Death Valley

b. Death Valley is a tectonically active region

How do monoclines form? a. Ductile sedimentary rock layers downwarp. b. Movement along a steep fault in basement rock pushes up a portion of the ductile rock layers above it. c. Compressional forces pushing toward each other fold ductile rock layers into a downward arch. d. Compressional forces pushing toward each other fold ductile rock layers into an upward arch. e. Basement rock is uplifted, which upwarps the ductile rock layers above it.

b. Movement along a steep fault in basement rock pushes up a portion of the ductile rock layers above it.

What is elastic deformation? a. The permanent deformation of a rock caused by the sudden application of stress. During elastic deformation, the chemical bonds within the rock break. b. The temporary and reversible deformation of a rock caused by the gradual application of stress. During elastic deformation, the chemical bonds within the rock do not break. c. The temporary and reversible deformation of a rock due to the gradual application of stress. During elastic deformation, the chemical bonds within the rock break. d. The permanent deformation of a rock due to the gradual application of stress. During elastic deformation, the chemical bonds within the rock do not break. e. The permanent deformation of a rock due to the gradual application of stress. During elastic deformation, the chemical bonds within the rock break.

b. The temporary and reversible deformation of a rock caused by the gradual application of stress. During elastic deformation, the chemical bonds within the rock do not break.

What produces plunging folds? a. a combination of rotating and tilting b. a combination of folding and tilting c. a combination of folding and rotating

b. a combination of folding and tilting

What is a syncline? a. a fold shaped like an upside-down U b. a fold shaped like a right-side-up U c. a fault shaped like an upside-down U d. a fault shaped like a right-side-up U

b. a fold shaped like a right-side-up U

What is a fault? a. fractures along which rocks bend b. fractures along which rocks move c. folds along which rocks move d. folds along which rocks bend

b. fractures along which rocks move

Choose the correct definition of a monocline: a. A convex-up fold with the oldest strata in the center b. A trough with the youngest strata occupying the center c. A large steplike fold in otherwise flat-lying sedimentary rocks d. A circular structure formed by downwarping of the crust e. A circular structure formed by crustal upwarping

c. A large steplike fold in otherwise flat-lying sedimentary rocks

Which of the following is required for a monocline to form? a. Subsidence produced by large accumulations of sediment b. Intrusion of magma (laccoliths) c. Reactivation of steeply-dipping faults in basement rocks d. Erosion of overlying sedimentary rocks e. Ductile deformation of crystalline basement rocks

c. Reactivation of steeply-dipping faults in basement rocks

Which type of force causes folding? a. tensional force b. shear force c. compressional force

c. compressional force

A monocline is a type of a(n) ____ a. intrusion b. anticline c. fold d. joint e. fault

c. fold

Which tectonic stress will result in a lengthening of the crust? a. compression b. shear c. tension

c. tension

Which type of force is responsible for normal fault formation? a. shear force b. compressional force c. tensional force

c. tensional force

The split cinder cone along the Southern Death Valley Fault is evidence that __________. a. the cinder cone formed in two separate volcanic episodes, producing two distinct parts b. magma rose along the fault, wedging and splitting the cinder cone into two parts c. the Pacific and North American plates are moving alongside each other along strike-slip faults d. an entire mountain slid off the Black Mountains along a low angle fault with a force great enough to split the cinder cone e. the Basin and Range province is stretching like taffy

c. the Pacific and North American plates are moving alongside each other along strike-slip faults

What are rocks below and above a fault called? a. the lower wall below and the upper wall above b. the hanging wall below and the footwall above c. the footwall below and the hanging wall above d. the lower wall below and the hanging wall above e. the footwall below and the upper wall above

c. the footwall below and the hanging wall above

What is a scarp? a. folded strata that were originally deposited in flat, horizontal layers b. preserved, wave-cut shoreline of an ancient lake c. the trace of a fracture called a normal fault, where a portion of crust slides down the fault surface d. a bedding plane that remains horizontal even during an episode of normal faulting e. upheaved rocks found along a fault line

c. the trace of a fracture called a normal fault, where a portion of crust slides down the fault surface

How do geologists infer the orientation of rock structures that are mainly below Earth's surface? a. After measuring the strike and dip of a single outcrop, geologists graphically present this datum in the form of geologic maps as a representation of all of the rocks in the area. b. Geologists only describe rock structures that they can see and say that there is no data for rock structures that cannot directly be seen. c. Geologists drill a core into several layers of rock strata every few feet and then sketch a cross section of underground rock layers by comparing the cores. d. After measuring the strike and dip of several outcrops within an area, geologists graphically present these data in the form of geologic maps. e. Geologists dig mines underground to directly study the orientation of rock layers.

d. After measuring the strike and dip of several outcrops within an area, geologists graphically present these data in the form of geologic maps.

Which of the following scenarios best describes the deformation that will occur in different parts of the crust? a. Folding and fracturing only occur in the shallow crust, where there is less confining force. b. Ductile deformation is dominant in the shallow crust; brittle deformation is dominant in the deep crust. c. Folding and fracturing only occur in the deep crust, where there is more tectonic force. d. Brittle deformation is dominant in the shallow crust; ductile deformation is dominant in the deep crust.

d. Brittle deformation is dominant in the shallow crust; ductile deformation is dominant in the deep crust.

What is rock deformation, and how might a rock body change during deformation? a. Deformation is a rock's reaction to stress, which can cause a rock to change its shape or mass. b. Deformation is a rock's reaction to strain, which can cause a rock to change its shape or position. c. Deformation is a rock's reaction to strain, which can cause a rock to change in mass or position. d. Deformation is a rock's reaction to stress, which can cause a rock to change its shape or position. e. Deformation is a rock's reaction to stress, which can cause a rock to change in mass or position.

d. Deformation is a rock's reaction to stress, which can cause a rock to change its shape or position.

The Basin and Range consists of north-south trending mountain ranges separated by basins. What causes this distinct topography? a. Large lakes that existed when climate was cooler and wetter filled the space between mountains to form basins. b. Volcanic activity formed the tall mountain ranges as the North American Plate moved westward over a stationary magma plume. c. During the Mesozoic, compression folded the rock layers to form tall mountains and intervening basins. d. Extension due to normal faulting causes valley floors to sink. e. As weathering and erosion occurs, intrusive rocks are exposed, which form the cores of the mountain ranges.

d. Extension due to normal faulting causes valley floors to sink.

Based on what you learned in the video, which of the following statements regarding joints is true? a. Joints are only formed in sedimentary rocks. b. Joints result from ductile deformation of rocks deep in the Earth's crust. c. Joints are cracks in rocks where movement has occurred on one side with respect to the other. d. Joints are fractures in rocks where very little to no movement has occurred. e. Joints and faults are the same thing.

d. Joints are fractures in rocks where very little to no movement has occurred.

Imagine an anticline has been eroded to a flat surface. How would the rock age change as you walked across that flat surface? a. Rocks would be youngest on the left and oldest on the right. b. Rocks would be oldest on the edges and youngest in the middle. c. Rocks would be youngest on the right and oldest on the left. d. Rocks would be youngest on the edges and oldest in the middle.

d. Rocks would be youngest on the edges and oldest in the middle.

What is an anticline? a. a fold shaped like a right-side-up U b. a fault shaped like a right-side-up U c. a fault shaped like an upside-down U d. a fold shaped like an upside-down U

d. a fold shaped like an upside-down U

What does the term plunging fold mean? a. a fold that is faulted down into Earth b. a fold that is pushed down into Earth c. a fold that is bent down into Earth d. a fold that is tilted down into Earth e. a fold that is synclined down into Earth

d. a fold that is tilted down into Earth

Which type of fault has NO vertical motion of rocks associated with it? a. normal fault b. shear fault c. reverse fault d. strike-slip fault

d. strike-slip fault

_____ are shown in the photo above. They are characterized by _____ sedimentary rock layers. a. fractures, continuous b. faults, continuous c. folds, discontinuous d. joints, continuous e. faults, discontinuous

e. faults, discontinuous