Transportation of Soil by Gravitational Forces

Gravitational forces play a significant role in the transportation of soil. When soil particles become dislodged and move downslope under the influence of gravity, it is known as mass wasting. The following type of soil is transported by gravitational forces:

a) Talus

Talus is a type of soil or rock debris that accumulates at the base of a slope or cliff due to gravitational forces. It is formed when rock fragments or soil particles detach from the slope and fall to the base, creating a cone-shaped pile. Talus deposits are commonly found at the foot of steep slopes or cliffs.

Explanation:

When weathering and erosion processes weaken the slope or cliff, the force of gravity causes the detached rock fragments or soil particles to fall freely. As a result, they accumulate at the base, forming a talus slope. This process is known as talus deposition or talus accumulation.

The transportation of talus occurs through a series of steps:

1. Weathering: The initial step involves the weathering of rocks or soil on the slope or cliff face. This can occur due to physical, chemical, or biological processes.

2. Detachment: Once the rocks or soil particles are weathered and weakened, they become detached from the slope or cliff face. This detachment can happen in the form of rockfalls, landslides, or other mass wasting events.

3. Free Fall: The detached fragments or particles then fall freely under the force of gravity. They gain momentum and velocity as they descend down the slope.

4. Accumulation: As the particles reach the base of the slope, they come to a rest and accumulate to form a talus slope. The accumulation process is influenced by the angle of repose, which is the maximum slope angle at which loose material can rest without sliding.

5. Stability: Over time, the talus slope reaches a state of stability where the rate of accumulation is balanced by the rate of weathering and erosion. However, talus slopes are dynamic features that can continue to evolve through ongoing weathering and mass wasting processes.

In conclusion, talus is a type of soil that is transported by gravitational forces. It is formed when rock fragments or soil particles detach from a slope or cliff face and accumulate at the base, creating a cone-shaped pile known as a talus slope.