The Main Postglacial Raised Beach
Detail of the base of the raised beach, with a dyke of till injected into an open joint of the raised shore platform
The section facing Skateraw Harbour shows the Main Postglacial Raised Beach, deposited around 5500 years ago. It was a high energy storm beach, with abundant shell debris. The raised beach rests on a raised shore platform which seems to have been refashioned from existing old platform. Open joints in the limestone contain plugs of till and the platform on the east side of Skateraw Harbour shows a cover of till.
The outer shore platform at Chapel Point. On the right, a zone of abrasion; on the left, a zone of undercutting and block release at the edge of the limestone bed.
Significance: an extensive shore platform developed across Carboniferous Limestone that shows a variety of processes of weathering and erosion, backed by a raised rock platform and raised beach
This shore platform is up to 300 m wide and dips gently seawards. The Chapel Point Limestone dips west so that a small cliff faces into Skateraw Harbour. Moving seawards from the edge of the raised beach we find a sequence of process zones:
1. above the high water mark, subaerial solution processes dominate. The joints are open. Small weathering pits are being deepened by carbonation and salt weathering (left).
It is clear that the platform is being lowered by a range of processes. Assuming that the modern platform has been fashioned from the higher platform below the raised beach, the long term rate of lowering is around 1 m in 5000 years.