| Wadhurst Clay Formation | |
|---|---|
| Stratigraphic range: | |
 Wadhurst Clay (grey) exposed at Bexhill Brick Pit | |
| Type | Geological formation |
| Unit of | Wealden Group |
| Underlies | Tunbridge Wells Sand Formation |
| Overlies | Ashdown Formation |
| Thickness | 30 to 78 m |
| Lithology | |
| Primary | Shale, Mudstone |
| Other | Siltstone, Sandstone, Limestone, Ironstone |
| Location | |
| Region | Europe |
| Country |  UK |
| Extent | Weald Basin |
| Type section | |
| Named for | Wadhurst |
The Wadhurst Clay Formation is a geological unit which forms part of the Wealden Group and the middle part of the now unofficial Hastings Beds. These geological units make up the core of the geology of the High Weald in the English counties of West Sussex, East Sussex and Kent.
The other component formations of the Hastings Beds are the underlying Ashdown Formation and the overlying Tunbridge Wells Sand Formation. The Hastings Beds in turn form part of the Wealden Group which underlies much of southeast England. The sediments of the Weald, including the Wadhurst Clay Formation, were deposited during the Early Cretaceous Period, which lasted for approximately 40 million years from 140 to 100 million years ago. The Wadhurst Clay is of Early to Late Valanginian age.[1] The Formation takes its name from the market town of Wadhurst in East Sussex.
- ^ Hopson, P.M., Wilkinson, I.P. and Woods, M.A. (2010) A stratigraphical framework for the Lower Cretaceous of England. Research Report RR/08/03. British Geological Survey, Keyworth.