The Coastal Zone: Distinctive Landforms 1

Seite 1

Physical Geography - Section B - The Coastal Zone

Distinctive Landforms

Rates of erosion are affected by:

Weathering: Sub aerial attack on cliffs. Speeds up erosion

Human activity above cliffs

Wave energy: Greater when waves are big and frequent

Rock Structure: Cliffs with many weaknesses called joints and cracks are more easily eroded

Beaches: Beaches in front of cliffs absorb wave energy slowing down erosion

Rock type: Resistant rocks such as granite erode very slowly. Less resistant rocks such as clays erode very quickly

The constant process of coastal erosion forms features in the coastal lines around the British Isles.

Cliffs and wave cut platforms (a wave cut platform may be created in front of a cliff)

It is important to remember that a cliff made from soft rock will erode quickly and form a gently sloping cliff. Hard rock creates steep cliffs.

1. Hydraulic action, abrasion and corrosion attacks the coastline between the high and low water marks. This creates a notch at the base of the cliff and an overhang above

2. The cliff above collapses

3. Over time the collapsed material erodes to form beach material and the cliff retreats leaving a wave cut platform