Weathering

mechanical weathering = the disintegration of rocks. Where this happens, piles of rock fragments called screen be found at the foot of cliffs.
chemical weathering = caused by chemical changes. Rainwater, which is slightly acidic, very slowly disintegrates certain types of rocks and minerals.
freeze-thaw action = in the day, water collects in cracks in the rocks. At night, the water freezes to form ice and expands and causes stress, and the cracks enlarge. After being repeated over a large amount of time, rock fragment breaks off and collects as scree at the foot of the rock face.

Mass Movement

it is the downslope movement of rocks, soil or mud under the influence of gravity
There are several types of movement:
rock slides = on a steep-is slope, rock breaks apart and slides down a glide plane, and at the impact point at the bottom, the rock breaks into debris, along with more debris from previous rock slides
Mud slides = on a steep-is slope, weathered loose material mixes with water and slides down a hill as mud.
Slumping = has a concave slip plane so material is rotated back into the cliff face as it slips.
Slides = these take place on steep cliff faces. Weathering has taken place on the sides and there are joints and cracks in the bedding planes. There is scree at the bottom.

	Created by Millie Balcombe about 5 years ago

GCSE Geography Slide Set on Geography KA1, created by Millie Balcombe on 04/11/2019.