CAUSES OF LANDSLIDES
Landslides are associated with:
- Steep slopes, [near the angle of collapse]
- Permeable rocks, [which let water through]
- Water in the soil and rock, [which lubricates the ground making it more unstable]
- Human activity – waste tips from mining & road cuttings, [makes steeper slopes]
Why does Wales have many landslides?
Because a combination of the above factors often occurs.
- Steep slopes in glaciated valleys and coastal cliffs
- In the S Wales coalfield there are alternating permeable sandstone and impermeable clay layers [clay stops rainwater seeping any further into the ground so the permeable layers above become saturated and springs form]
- N Wales is one of the wettest areas of the UK
- Coal mining in S Wales, construction of major coastal roads in N Wales
Why should we be concerned about landslides?
- It is predicted that climate change will bring wetter winters and more intense stormy conditions. [ Future climate change in Wales]
- These are just the conditions that will cause more landslides in Wales.
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 Landscape, Blaencwm, Rhondda Valley, South Wales
© Photolibrary Wales
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