Landslides and Mass Wasting Review Flashcards
What is the primary force responsible for all types of erosion on Earth?
Gravity
Which factor can decrease the strength of sediment and contribute to landslides?
To much water
Why are steep slopes more prone to landslides than gentle slopes?
Shear force is greater
What triggered the largest landslide in recorded history?
5.1 earthquake
How do tree roots help prevent landslides?
Binding soil together
What is a talus slope?
Steep slope with rocks
What type of mass wasting occurs when rock material moves as a thick fluid?
A flow
What is a lahar?
gravity-driven mudflow or debris flow that occurs on volcanoes
How many people were killed by the lahar in the Philippines in 1991?
187
How can landslides affect aquatic ecosystems?
Causing sedimentation
What was one of the first plants to grow after the Mount St. Helens landslide
Prairie
How fast did the rock material travel during the Mount St. Helens landslide?
70-150 miles per hour
What term describes the downhill movement of rock and soil caused primarily by gravity?
Mass wasting
How do suspended sediments from landslides affect underwater plants?
Reducing high penetration
What happens when clay gets wet during a landslide event?
Slippery mud
Which natural event can remove trees and increase landslide risk?
Wildfires
What type of mass wasting occurs when a mass of rock slides as one block along a curved
surface?
Slump
How can human activities contribute to landslide risk
Deforestation
What process describes how ecosystems change over time after a landslide
Ecological succession
- What role do tree roots play in soil moisture control?
Absorbing water
