Question

Which of the following statements about rockslide is correct?

• A. It affects only the outermost layer of the rock face
• B. It is slower than rock fall
• C. It involves backward rotation of debris
• D. It affects material to considerable depth

Answer 1

Answer:

D. It affects material to considerable depth

• Definition: A rockslide is a type of mass wasting or landslide that involves the downslope movement of detached blocks of bedrock along a planar surface or failure plane.

• Depth Factor: Unlike surface-level creep or surficial soil slips, a rockslide typically involves the movement of material to a considerable depth, often mobilizing large volumes of rock and debris.

• Geological Mechanism: These events are frequently triggered by geological weaknesses such as bedding planes, fractures, fault lines, or foliation planes that provide a lubricated or weakened surface for sliding.

• Speed and Magnitude: Rockslides are characterized by rapid, often catastrophic movement. The high-velocity nature is driven by gravity and can lead to the formation of a debris fan or talus slope at the base of the mountain.