Question

which type of mass movement occurs the fastest? a. earthflow b. rockfall c. slump d. creep

Explanation:

To determine the fastest mass movement, we analyze each option:

• Earthflow: A type of mass movement involving saturated soil and debris, but not the fastest.
• Rockfall: Occurs when rocks fall freely from a cliff or steep slope, often at high speeds due to gravity and the lack of resistance during free fall.
• Slump: A slower, rotational movement of rock or soil along a curved surface.
• Creep: The slowest mass movement, involving gradual downslope movement of soil and rock over time.

Among these, rockfall (Option B) typically occurs the fastest as rocks can fall rapidly under gravity.

Answer:

B. rockfall