Kimmeridge Clay

Kimmeridge Clay Stratigraphic range: Upper Jurassic
Grey cliffs of Upper Kimmeridge Clay above the beach at Egmont Bight
Type	Geological formation

The Kimmeridge Clay Formation is a sedimentary deposit of fossiliferous marine clay which is of Jurassic age. It occurs in Europe.

Kimmeridge Clay is arguably the most economically important unit of rocks in the whole of Europe, being the major source rock for oil fields in the North Sea hydrocarbon province. It has distinctive physical properties, log responses, and palynological signature.

It is named after the village of Kimmeridge on the Dorset coast of England, where it is well exposed and forms part of the Jurassic Coast World Heritage Site. It exists across England, in a band stretching from Dorset in the south-west, north-east to East Anglia.

The Humber Bridge's foundations are in the Kimmeridge Clay deposits under the Humber estuary.

The fossil fauna of the Kimmeridge Clay includes a reptile fauna of turtles, crocodiles, sauropods, plesiosaurs, pliosaurs and ichthyosaurs, as well as a number of invertebrate species.

Vertebrate fauna

Archosaurs

Thalattosuchians

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	Location	Member	Abundance	Notes	Images
Cricosaurus	C. gracilis				A metriorhynchine metriorhynchid
Dakosaurus	D. maximus				A geosaurine metriorhynchid
Metriorhynchus	M. geoffreyi				A metriorhynchine metriorhynchid
Plesiosuchus	P. manseli				A geosaurine metriorhynchid
Steneosaurus	S. megarhinus				A teleosaurid
Torvoneustes	T. carpenteri				A geosaurine metriorhynchid
	T. coryphaeus				A geosaurine metriorhynchid

Ornithischians

Indeterminate nodosaurid remains have been found in Wiltshire, England. Indeterminate stegosaurid remains have been found in Dorset and Wiltshire, England.

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	Location	Member	Abundance	Notes	Images
Cumnoria	C. prestwichii	Oxfordshire		"Fragmentary skull and skeleton."
Dacentrurus	D. armatus	Cambridgeshire Dorset Wiltshire			Wiltshire remains include specimens previously referred to Omosaurus armatus and O. hastiger.	Dacentrurus
Ornithopoda	Indeterminate	Dorset?			Kimmeridge clay remains considered to represent a possible close relative of Bugenasaura are now regarded as the remains of an indeterminate euornithopod.(The specimen may have had its locality and horizon mislabelled.)
Omosaurus	O.armatus	Wiltshire			Reclassified as Dacentrurus armatus because the generic name Omosaurus was preoccupied.
	O. hastiger	Wiltshire

Saurischians

Indeterminate ornithomimmid remains have been found in Dorset, England. An undescribed theropod genus was found in Dorset.

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Bothriospondylus	B. suffosus	Wiltshire		"[Seven] dorsal and sacral centra."
Cetiosaurus	C. humerocristatus	Dorset			Now Duriatitan.
	Indeterminate	Oxfordshire			Remains previously referred to an indeterminate species of Cetiosaurus are now regarded as indeterminate sauropod material.
Duriatitan	D. humerocristatus	Dorset		Humerus	A titanosauriform
Gigantosaurus	G. megalonyx	Cambridgeshire			Remains previously referred to Gigantosaurus megalonyx are now regarded as indeterminate sauropod material.
Ischyrosaurus	I. manseli	Oxfordshire		"Humerus."	Remains previously referred to Ischyrosaurus manseli are now regarded as indeterminate sauropod material.
Juratyrant	J. langhami	Dorset		Partial skeleton	A tyrannosaur
Theropoda	Indeterminate	Wiltshire Dorset			Remains previously referred to Megalosaurus are now regarded as indeterminate theropod material.
Sauropoda	Indeterminate	Oxfordshire Cambridgeshire Norfolk			Remains previously attributed to one or more indeterminate species of Ornithopsis (incl. O. leedsii) are now regarded as possible indeterminate sauropod material.

Plesiosaurs

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Genus	Species	Location	Member	Abundance	Notes	Images
Bathyspondylus	B. swindoniensis				Plesiosaur of unknown affinities
Colymbosaurus	C. megadeirus				A cryptoclidid
	C. trochantericus				Nomen dubium
Kimmerosaurus	K. langhami				A cryptoclidid
Plesiosaurus	"P." manseli				Distinct from Colymbosaurus.
Pliosaurus	P. brachydeirus				A thalassophonean pliosaurid
	P. brachyspondylus				Nomen dubium
	P. carpenteri				A thalassophonean pliosaurid
	P. kevani				A thalassophonean pliosaurid
	P. macromerus				Nomen dubium; formerly classified in the separate genus Stretosaurus
	P. portentificus				A thalassophonean pliosaurid
	P. ?rossicus				A thalassophonean pliosaurid; taxonomic identification of specimens tentative
	P. westburyensis				A thalassophonean pliosaurid
	P. sp. 1			Partial skeleton, CAMSM J.35991	A thalassophonean pliosaurid; previously assigned to the nomen dubium P. brachyspondylus
	P. sp. 2			Mandible, NHMUK PV OR 39362	A thalassophonean pliosaurid; previously assigned to the nomen dubium P. macromerus
Spitrasaurus	Indeterminate

Invertebrates

An aptychus with the name "Trigonellites latus", from the Kimmeridge Clay Formation

The invertebrate fauna of the Kimmeridge Clay includes:

• Mollusca:
  • Cardium striatulum
  • Ostrea deltoidea
  • Gryphaea (Exogyra) virgula
  • The ammonite aptychus known as "Trigonellites latus"
  • Belemnotheutis

See also

• List of dinosaur-bearing rock formations

References

• Galton, P.M. 1999. Cranial anatomy of the hypsilophodontid dinosaur Bugenasaura infernalis (Ornithischia: Ornithopoda) from the Upper Cretaceous of North America. Revue Pale´obiologie, 18, 517–534.
• Martill, D.M., Naish, D. & Earland, S. 2006. Dinosaurs in marine strata: evidence from the British Jurassic, including a review of the allochthonous vertebrate assemblage from the marine Kimmeridge Clay Formation (Upper Jurassic) of Great Britain. In: Colectivo Arqueologico y Paleontologico Salense, (ed.) Actas de las III Jornadas Intrernacionales sobre Paleontologı´a de Dinosaurios y su Entorno, 16–17 Sep. 2004. Salas de los Infantes, Burgos, 47–84.

• Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Jurassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 545–549. ISBN 0-520-24209-2.
• "Table 19.1," in Weishampel, et al. (2004). Page 415.
• "Table 13.1," in Weishampel, et al. (2004). Page 270.
• "Table 13.1," in Weishampel, et al. (2004). Page 267.
• "Table 13.1," in Weishampel, et al. (2004). Page 271.
• Benson, R.B.J. (2008). "New information on Stokesosaurus, a tyrannosauroid (Dinosauria: Theropoda) from North America and the United Kingdom." Journal of Vertebrate Paleontology, 28(3):732-750. doi:10.1671/0272-4634(2008)28[732:NIOSAT]2.0.CO;2.
• Brusatte, S.L. and Benson, R.B.J. (2013). "The systematics of Late Jurassic tyrannosauroids (Dinosauria: Theropoda) from Europe and North America." Acta Palaeontologica Polonica, 58(1): 47-54. doi:10.4202/app.2011.0141
• Benson RBJ, Bowdler T. 2014. Anatomy of Colymbosaurus (Reptilia, Plesiosauria) from the Kimmeridge Clay Formation of the U.K., and high diversity among Late Jurassic plesiosauroids. Journal of Vertebrate Paleontology 34(5), 1053-1071.
• Low resolution pdf High resolution pdf
• http://www.fullbooks.com/The-Student-s-Elements-of-Geology7.html The Student's Elements of Geology by Sir Charles Lyell Part 7 out of 14 accessed 13 February 2009.