Mass Movement

Question 1

Mass Movement

Answer 1

Mass movement is the movement of material downslope under the influence of gravity.

Question 2

Soil Creep

Answer 2

The slowest but most continuous form of mass movement involving the movement of soil particles downhill. Particles rise and fall due to wetting and freezing and this causes the soil to move down the slope.

Question 3

Mudflows

Answer 3

An increase in the water content of soil can reduce friction. Water can get trapped within the rock increasing the Pore Water Pressure, which forces rock particles apart and therefore weakens the slope.

Mudflows represent a serious threat to life as they can be very fast flowing.

Question 4

Rockfalls

Answer 4

These occur on cliffs undercut by the sea or sloped cliffs exposed to mechanical weathering.

Question 5

Landslides

Answer 5

Heavy rainfall leads to water between joints and bedding planes in cliffs, which can reduce friction and lead to a landslide. Occurs on cliffs made from softer rocks or deposited material. Blocks of intact rocks moves down the cliff face very quickly along a flat slope.

Question 6

Slumping

Answer 6

Where softer material overlies much more resistant materials, the slope is curved. A build up in pore water pressure leads to the land to collapse under its own weight. Producing a rotational movement.

Question 7

Run-Off

Answer 7

When heavy rain washes material from the surface of a cliff over the edge and down onto the shore. The presence of which will assist many of the mass movement processes.