* Mass movement: This is a general term for the downslope movement of rock, soil, or other debris under the influence of gravity.

* Sudden: This indicates a rapid, uncontrolled movement, not a slow creep.

* Applied Materials: This likely refers to the material that is moving (rock, soil, etc.).

* Long E-flat inclined surface: This describes a steep slope that provides the necessary force of gravity to initiate the movement.

Rockfalls occur when individual blocks of rock detach from a cliff face or steep slope and fall freely. Rock slides are more complex and involve a larger mass of rock that moves along a defined plane, often triggered by rainfall or seismic activity.

Important Note: The term "E-flat" is not a standard geological term. If this is a specific geological feature, please provide more information for a more accurate answer.