Discordant Coast - the structure and alignment of these rocks have a significant effect on the landforms produced. This is a discordant coast where the geological sequence has produced distinctive coastal landforms. At Old Harry/Ballard Point and at Durlston Head are outcrops of rocks resistant to erosion. The chalk escarpment which bends from St Oswald's Bay eastwards to Old Harry increases in width to produce steep 60 metre cliffs. Erosion at the chalk headland of Ballard Point has produced stacks, wave cut platforms, notches, caves and arches.
The more resistant Portland limestone has also produced vertical