The diagram illustrates the progress of headland erosion overtime, by showing in four stages.
In the first stage, the waves attack the weakness area of the headland through processes. This lead to the information that have a small cracks, which is gradually develop into caves. In the second stages, the erosion continues and the caves expands and eventually turn to an arch. As we know, Durdle Door, Desert.
In the third stages, the headland weakens due to ongoing waves pressure. Meanwhile, the roof becomes unstable, the leaving behind rock called a stack. Over time, the waves continue collisions with the stack, causing it to weakness future. In the final stage, the stack eventually collapses,forming a smaller structure known as a stump.
Overall, the diagram shows how the headland erosion gently transforms the landscape. The sea forces of the sea break down the rock formations, reshaping the coastline over time.