Exam 15: Mass Wasting

Which type of motion will supply material to and maintain talus slopes?

Fast mass-wasting processes are more widespread than slow mass-wasting processes.

What is the angle of repose?

What is the angle of repose for a sediment such as sand?

Which scenario led to the disaster that destroyed the city of Armero in 1985?

Which of the following locations would be most likely to see large-scale, rapid mass wasting?

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)led to the mass wasting at Rich's house and why?

Low, old, rounded terrain is actively undergoing mass wasting.

Central Wisconsin and south-central Minnesota both have regions with the potential for landslides.However, neither of these locations is located in mountainous areas.Why might landslides occur in these specific regions?

What is the risk for landslides in West Virginia?

Identify the mass-wasting event in this image.

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?

Which would be the most likely location for a rockslide to occur?

Why might West Virginia have the landslide risk that it does?

Rockfalls are the primary way in which talus slopes are built and maintained.

One main cause of creep is

Slow forms of mass wasting such as creep and solifluction are considered slow because they are restricted to gentle slopes and cannot achieve a high velocity.

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 has on sediments in a slope.What role does water play to maintain a slope? What role does water play to cause mass wasting of the slope?

Which factor exerts the greatest control over the velocity of debris flows and the distance they will travel?

Grasses will result in more slope stability than trees.