The downslope movement of a body of material made up of soil, sediment, or rock propelled by the force of gravity is known as:

Mass movement

Explanation: Mass movement is the natural process that occurs under the gravity force causing soil, sand, rocks to move in the downward motion in a slope in the form of solid mass. This process is also known as the mass wasting. along with mass movement , there is also the flow of debris and mud . It is usually caused by the climatic condition on the Earth's surface.

seismic wave -

an elastic wave in the earth produced by an earthquake or other means.

explanation:

you would travel west