Which of the following slope failures moves at the slowest rate?
A)Earth flow
B)Rock avalanche
C)Debris flow
D)Rock fall
E)Debris avalanche

Question

Quizplus · Accepted Answer

Earth flow is a type of slope failure that moves very slowly, typically on the order of a few meters per year. This is because the soil and rock fragments in an earth flow are held together by a cohesive matrix, which resists shearing and allows the material to deform and flow plastically. In contrast, rock avalanches, debris flows, and debris avalanches all involve much larger, more chaotic masses of material that can move at much higher speeds, ranging from tens to hundreds of kilometers per hour. Rock falls, meanwhile, typically have a relatively low volume and do not involve significant amounts of soil, so they can move at moderate to high speeds, depending on the slope angle and other factors.

Which of the Following Slope Failures Moves at the Slowest