Wadhurst Clay Formation

Wadhurst Clay Formation
Stratigraphic range: Valanginian PreꞒ Ꞓ O S D C P T J K Pg N
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.