Speeton Clay Formation

The Speeton Clay Formation (SpC)^[1] is a Lower Cretaceous geological formation in Yorkshire, northern England. Unlike the contemporaneous terrestrial Wealden Group to the south, the Speeton Clay was deposited in marine conditions. The most common fossils in the unit are belemnites, followed by ammonites and the lobster Meyeria ornata. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.^[2]

Speeton Clay Formation
Stratigraphic range: Berriasian-Albian 145–100 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Speeton Clay Formation at Reighton Sands, North Yorkshire
Type	Geological formation
Unit of	Cromer Knoll Group
Sub-units	Members A to D
Underlies	Hunstanton Formation
Overlies	Kimmeridge Clay Formation
Thickness	100 m (330 ft) in outcrop
Lithology
Primary	Claystone
Other	Glauconite
Location
Coordinates	54.2°N 0.2°W / 54.2; -0.2
Approximate paleocoordinates	41.0°S 9.3°E / -41.0; 9.3
Region	Yorkshire
Country	United Kingdom
Extent	North Sea Graben, eastern England
Type section
Named for	Speeton
Location of the formation

Meyeria ornata, a lobster from the Speeton Clay

The formation is named after the village of Speeton in North Yorkshire.

Fossil content

The following fossils have been reported from the formation:^[3]

• Reptiles
  • Ichthyosaurs
    • Acamptonectes densus^[4][5]
  • Neornithischians
    • Owenodon hoggii^[6]
    • Iguanodontia indet.^[7]
  • Sauropterygians
    • Elasmosauridae - "Speeton Clay plesiosaurian"^[8]
• Fish
  • Cretorectolobus doylei^[9]
  • "Dasyatis" speetonensis^[9]
  • "Protosqualus. sp"'
  • Notidanodon lanceolatus^[9]
  • Notorhynchus aptiensis^[9]
  • Synechodus dubrisiensis^[9]
  • Spathobatis rugosus^[9]
  • ?Sphenodus sp.^[9]
  • "Elops" neocomiensis^[9]
  • Pycnodontidae indet.^[9]
  • Semionotidae indet.^[9]
  • Teleostei indet.^[9]
  • ?Triakidae indet.^[9]
• Invertebrates
  • Crustaceans
    • Martillepas auriculum^[10]
  • Crinoids
    • Crinoidea indet.^[9]

See also

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with indeterminate dinosaur fossils