Understanding Coastal Erosion and Coral Reef Ecosystems
Cliffs and Wave-Cut Platforms
- Erosion is greatest when large waves actually break against the foot of a cliff.
- As the notch gets larger, the cliff above will become increasingly unsupported and, in time, will collapse.
- As the process is repeated, the cliff will slowly retreat and usually increase in height.
Caves, Arches, and Stacks
- Where headlands are formed, there is resistant rock, but they are still likely to contain areas of weakness.
- Areas of weakness will be the first to be worn away by the sea.
- First, a cave will form; later, an arch; and at the end, a stack (as the rock above the arch becomes unsupported, it collapses).
Types of Reefs
There are three types of reefs:
- Fringing Reef – Coral platforms grow out to sea attached to the mainland.
- Barrier