NORFOLK Museums Service
Pro-glacial thrusting at Sidestrand

Weybourne - Sheringham

Geology

Contorted drift at SheringhamThe cliffs to the west of Sheringham display good sections of the glacial sediments known as the Contorted Drift. At the bottom of the cliffs below Skelding Hill there are Lower Pleistocene deposits of the Pastonian stage, resting directly on Chalk.

The Crag-Chalk unconformity dips gently westwards along the North Norfolk coast. While at Weybourne to the west it is midway up the cliff, at Sheringham the unconformity has descended to the base of the cliff. Here you can examine the old erosion surface on the Chalk, on which the much younger tidal sediments are laid. Ther is usually a stonebed of large flints and then sands and gravels with occasional lenses of organic muds.

The Contorted Drift is the graphic name given to the deformed glacial sediments of North Norfolk. It is essentially a reworking of earlier glacial materials, with the addition of Chalk and sand. The ingredients are seen here in the process of being folded and sheared. They were being incorporated into the till, but the process is incomplete. So, here in Sheringham cliffs we can see the formation of a glacial till, but like a cake that is not yet properly mixed the ingredients of chalk, sand and mud can still be seen in streaks and pods.

Paradoxically it is the least deformed glacial materials, like these, that appear to be the most contorted. Extreme deformation, through shearing, leads to uniformly mixed ingredients. Tills that are homogenious hardly appear deformed at all.

Flint ammoniteThe Chalk is exposed on the foreshore and forms a resistant shoal (called Robin Friend) which is exposed at low spring tides. In this area and eastwards, rare flint ammonites are occasionally expose. Evidently the chemical conditions within the chambers has encouraged the formation of flint. As the inception of this type of diagenesis is related to the organic chemistry of the decaying ammonite, it is sometimes possible to preserve features of the soft parts of the ammonite body.

Getting There

Park in a street / car park within Sheringham or at Weybourne beach. The beach is best reached from Sheringham Promenade or Weybourne beach.