Geology test (doesn't rock) -____-
Which of the following responses are examples of how water can promote mass wasting?
-Water can saturate sediment, reducing the integrity of the slope and allowing it to move. -Waves and streams can undercut banks and cliffs, causing them to fail. -When water is added to weathered particles, the mass of the sediment is increased, which can cause slope instabilit
How can the addition of water make a slope fail, creating a landslide?
-Water makes the slope material heavier. -Water in pore spaces reduces cohesion between particles. -Water can easily flow downslope.
What percentage of Earth's water is in the form of seawater?
97.2%
In the hydrologic cycle, water that falls on land in the form of precipitation returns to the ocean in which of the following pathways?
All of the responses are correct.
The creation of which sedimentary feature is controlled in part by debris flows exiting a narrow canyon?
Alluvial fan
Why might West Virginia have the landslide risk that it does?
Appalachian Mountains
How might a wildfire influence mass wasting?
Because plants on a slope bind the regolith with their roots and shield the soil surface from raindrops, a wildfire that destroys these plants would render the soil looser and more susceptible to the erosional forces of rain.
Which of the following scenarios would lead to a mass wasting event due to an oversteepened slope?
Construction of buildings on slopes
The ________ is an elevational point that divides an entire continent into large drainage basins.
Continental Divide
Which of the following statements about the global water supply is true?
Decreased precipitation could impact water supply available for humans.
Describe how a soil particle moves downhill during the freeze-thaw process.
During the freeze, a soil particle moves at a right angle away from the surface, and thawing causes the particle to fall back to a slightly lower level.
Which type of motion will supply material to and maintain talus slopes?
Fall
In which direction is mass wasting occurring in this image?
From left to right
Which of the following factors does not influence mass wasting?
Geologic age
A piece of gravel is resting on a slope. Which of the following best describes how the gravitational force pulling the gravel downward will vary with the inclination of the slope?
Gravitational force will decrease as the slope angle decreases.
What is the controlling force of mass wasting?
Gravity
Which of the following landslides was caused in part because the underlying sedimentary bedrock was oriented parallel to the slope that failed?
Gros Ventre Landslide
Assume this house is located in central Alaska. What did this house do to the local landscape to end up so misaligned?
Heat from the house melted the permafrost below.
The ________ describes the path water takes as it moves between the land, the ocean, and the atmosphere.
Hydrologic Cycle
What is the significance of the angle of repose in regard to mass wasting?
If a slope becomes any steeper than the angle of repose, then material will start moving downslope via mass wasting.
What nongeologic term is commonly used to describe a sudden event in which large volumes of material move down steep slopes?
Landslide
What is mass wasting, and how does it differ from other erosional processes (e.g., streams, glaciers, wind)?
Mass wasting is the downslope movement of rock material driven by the force of gravity. It differs from other erosional processes in that mass wasting does not require a transporting medium.
Stream valleys are produced through combined effects of mass wasting and running water. If running water alone were responsible for creating stream valleys, how would they appear?
Narrow valleys with vertical walls
Which of the following will not oversteepen a slope and lead to mass wasting?
None of these
Streams generally receive their water from two sources. What are those two sources?
Overland flow and groundwater
What is the fastest form of mass wasting?
Rock avalanche
Which one of the following locations would be most likely to have the mass wasting process visible here?
Siberia
Which slope composition is the most stable?
Solid bedrock
Assuming this location is near the Arctic Circle, what kind of mass wasting is visible in this image?
Solifluction
during which season does solifluction occur in the Arctic, and why?
Solifluction occurs during the Arctic's summer, when the top meter or so of the active layer thaws. Because the resulting meltwater has nowhere to go, it saturates the active layer, causing it to slowly flow.
Why doesn't sea level drop even though oceans have a higher rate of evaporation than precipitation?
Surface water running off into the oceans makes up the difference between evaporation from the oceans and precipitation into the oceans, creating a balance.
Which of the following correctly states the role of rivers and mass wasting in the formation of the Grand Canyon?
The Colorado River erodes downward, then mass-wasting processes move material from high to low areas, then the Colorado River transports material downstream.
Which of the following locations would be most likely to see large-scale, rapid mass wasting?
The Rocky Mountains
Define mass wasting.
The downslope movement of sediment and rock under the direct influence of gravity.
When considering the movement of water on Earth within the hydrologic cycle, which of the following choices is responsible for driving this process?
The hydrologic cycle works because water exists on Earth in solid, liquid, and gaseous states.
What is the mouth of a stream?
The location where one stream flows into another body of water
What is the angle of repose?
The steepest angle at which a material remains at rest
When dry sediment accumulates, the angle of repose represents what property of the deposit?
The steepest angle at which those sediments can accumulate and remain stable.
What will happen to the water level in the stream if the water table is below the level of the stream channel?
The stream will lose water to the groundwater system.
Why would trees be J-shaped?
The trunks become tilted in the downhill direction due to creep, but continue to grow toward the sun.
In what climate(s) is solifluction prevalent?
Tundra and subarctic
What is the risk for landslides in West Virginia?
Very high potential
What is infiltration?
Water soaking into the ground
The amount of meandering that occurs in a stream influences the gradient in which of the following ways?
With more meanders, the stream gradient decreases.
What is a stream's longitudinal profile?
a cross-sectional view of a stream from the headwaters to its mouth
What factors would decrease flow velocity?
a decrease in stream discharge a decrease in gradient of the stream having a rough channel
Particles moving by saltation are transported in the _______ load.
bed
Over time, mass wasting causes __________.
canyons to widen
What is the geologic definition of a stream?
channelized body of water flowing down gradient
Water in the hydrologic cycle readily moves from the land to the oceans through several pathways. How does the vast majority of water get from the ocean to the land surface?
clouds and precipitation
The process that causes dissolution of limestone bedrock in a stream is ______.
corrosion
What is the slowest form of mass wasting?
creep
Which of the following is monetarily, the most costly form of mass wasting? (I know the guy in the video didn't talk about this, but I did in lecture)
creep
Which of the following triggers generated the 1958 landslide and tsunami at Lituya Bay, Alaska?
earthquake
Describe the erosion occurring during headward erosion.
erosion backwards at the start of the stream
What are water gaps?
erosion through hills or ridges caused by a change in base level
According to the hydrologic cycle, once precipitation has fallen on land, what paths might the water directly take?
evaporation/transpiration infiltration into the ground runoff into a river runoff into the sea
One main cause of creep is
expansion and contraction of soils during freezing and thawing.
detached material moves in a free-fall.
fall
material moves downslope as a viscous fluid.
flow
When considering mass wasting, which of the following factors is most influential in the downslope movement of weathered particles?
gravity
Which of the following is the major contributing factor in all landslides?
gravity
Which of the following would increase flow velocity?
having a narrow, deep channel
Which of the following is the primary step that allows water to enter the groundwater system?
infiltration
Creep is __________.
mass wasting by the gradual downhill movement of sediment, influenced by freeze-thaw or wet-dry cycles
Which landscape is most prone to generating landslides?
mountains
Identify the mass-wasting event in this image.
mudflow
What type of drainage pattern develops on highly jointed bedrock?
rectangular
What rock type is the easiest for a river to cut through?
shale
mass movements in which there is a distinct plane of weakness between the slide material and underlying stable material.
silde
What terms are used to describe the way material moves during mass wasting?
slide flow fall
A __________ is formed when vertical incision by a stream is the primary process, with relatively minimal mass wasting.
slot canyon
Which of the following is associated with creep?
slow and subtle movement of material
A ________ is an example of a rotational slide.
slump
Which type of mass wasting forms a crescent-shaped scarp at the head of movement?
slump
Which of the following locations contains the most water in Earth's hydrosphere aside from the oceans?
the atmosphere
What will happen to the water level in the stream if the water table is below the level of the stream channel?
the stream will lose water to the groundwater system.
Which of the choices below is not a factor that causes infiltration and runoff to vary from place to place and from time to time?
time of the day
A ________ is not the sole cause of a mass wasting event, but the last of many causes that initiate the downslope movement of materials.
trigger
The weathering process of frost action can make a slope less stable.
true
