15.5 Essay Questions
1) The great multimillionaire Rich Mahn is building a new mansion on a steep bluff overlooking
a languid river below … or, at least he could look over the river if it weren’t for all the trees in the
way. Whipping out his cell phone, he calls a local landscaping company and has all of the trees
ripped out and the steep slope smoothed back into place. Several months later, Rich is making
another phone call, this time to a construction company. It seems that the bluff is eroding away at
an alarming rate and the ground that his new house is sitting on is being undermined. What
event(s) lead to the mass wasting at Rich’s house and why?
2) Imagine you are at the beach, building a sandcastle. Dry sand cannot hold a form, so the
addition of water is necessary to build the castle. However, too much water will destroy the
sandcastle and cause the sand to flow away in a slurry. This is similar to the role pore water will
have on sediments in a slope. What role will water play to maintain a slope? What role will water
play to cause mass wasting of the slope?
3) What role does fire play in making mass wasting more severe?
4) Compare and contrast rotational slides and translational slides.
5) Evaluate the statement, “All lahars are mudflows, but not all mudflows are lahars.”
6) What geologic and environmental factors contributed to the severity of the Gros Ventre
Landslide of 1925?
7) Compare and contrast earthflows and debris flows.
8) How can road construction in mountainous areas exacerbate mass wasting?
9) You are driving along a mountain highway built into the side of the mountain. The rock layers
making up the slope are oriented parallel to the slope. What are three ways that the slope could
be stabilized to reduce the likelihood of landslides?
10) Consider the topography and geology of your campus. Which forms of mass wasting do you
believe would be a problem for the school? Why?
11) Consider the topography and geology of your campus as well as the mass wasting hazards
present on your campus. What could your school do to mitigate these hazards? Based on the
hazards and the cost of mitigation, are these realistic plans? (Could your school afford to
implement them?)
1)
Using the arrows present in this image, identify the forces at work on a particle undergoing mass
wasting. List the forces next to the appropriate arrows.
2)
Using this image, consider the forces being illustrated with Arrows A, B, and C. Which scenario
do you think will be most likely to generate mass wasting: when Arrow C is longer than Arrow
A or when Arrow A is longer than Arrow C? Explain.
3)
This image shows Silurian dolomite along Lake Michigan at Cave Point County Park in
Wisconsin. Explain what factors are leading to mass wasting at this location. Also, what force is
causing the mass wasting?
4)
Identify the mass-wasting event in this image.
5)
Identify the mass-wasting event in this image.
6)
Identify the mass-wasting event in this image.
7)
What is the name of the bent shape of the tree trunks in this image?
8)
Explain the physical processes behind the tilted rock layers, curved tree trunks, and broken
retaining walls visible in this image.
9)
In which direction is mass wasting occurring in this image?
10)
Assume this house is located in central Alaska. What did this house do to the local landscape to
end up so misaligned?
11)
What is the risk for landslides in West Virginia?
12)
What is the reason for the landslide risk in West Virginia?
13)
Use this image to determine the landslide risk for your area.