Atherfield Clay Formation

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Atherfield Clay Formation
Stratigraphic range: Aptian
Cottages, Atherfield Point (geograph 5124463).jpg
Atherfield Point
Type Geological formation
Unit of Lower Greensand Group
Sub-unitsChale Clay Member
Underlies Ferruginous Sands, Hythe Formation
Overlies Vectis Formation, Weald Clay
Thickness55–60 m (180–197 ft) on the Isle of Wight, up to 18 m (59 ft) in the Weald
Lithology
Primary Mudstone
Other Sandstone, Ironstone
Location
Region Europe
CountryFlag of the United Kingdom.svg  UK
Extent Southern England

The Atherfield Clay Formation is a Geological formation in Southern England. Part of the Lower Greensand Group it dates to the Aptian age of the Early Cretaceous. The deposit is of marine origin largely consisting of massive yellowish brown to pale grey mudstones. [1] The pterosaur Vectidraco is known from the formation. [2] As is the Sandownid turtle Sandownia.

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Weald Clay

Weald Clay or the Weald Clay Formation is a Lower Cretaceous sedimentary rock unit underlying areas of South East England, between the North and South Downs, in an area called the Weald Basin. It is the uppermost unit of the Wealden Group of rocks within the Weald Basin, and the upper portion of the unit is equivalent in age to the exposed portion of the Wessex Formation on the Isle of Wight. It predominantly consists of thinly bedded mudstone. The un-weathered form is blue/grey, and the yellow/orange is the weathered form, it is used in brickmaking.

Kimmeridge Clay

The Kimmeridge Clay is a sedimentary deposit of fossiliferous marine clay which is of Late Jurassic to lowermost Cretaceous age and occurs in southern and eastern England and in the North Sea. This rock formation is the major source rock for North Sea oil. The fossil fauna of the Kimmeridge Clay includes turtles, crocodiles, sauropods, plesiosaurs, pliosaurs and ichthyosaurs, as well as a number of invertebrate species.

Wealden Group

The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimentary rocks of Berriasian to Aptian age and thus forms part of the English Lower Cretaceous. It is composed of alternating sands and clays. The sandy units were deposited in a flood plain of braided rivers, the clays mostly in a lagoonal coastal plain.

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Istiodactylus is a genus of pterosaur that lived during the Early Cretaceous period, about 120 million years ago. The first fossil was discovered on the English Isle of Wight in 1887, and in 1901 became the holotype specimen of a new species, O. latidens, in the genus Ornithodesmus. This species was moved to its own genus, Istiodactylus, in 2001; this name is Greek for "sail finger". More specimens were described in 1913, and Istiodactylus was the only pterosaur known from three-dimensionally preserved fossils for much of the 20th century. In 2006, a species from China, I. sinensis, was assigned to Istiodactylus, but it has also been suggested to belong to a different genus.

<i>Lonchodectes</i> Genus of lonchodectid pterosaur from the Late Cretaceous

Lonchodectes was a genus of lonchodectid pterosaur from several formations dating to the Turonian of England, mostly in the area around Kent. The species belonging to it had been assigned to Ornithocheirus until David Unwin's work of the 1990s and 2000s. Several potential species are known; most are based on scrappy remains, and have gone through several other generic assignments. The genus is part of the complex taxonomy issues surrounding Early Cretaceous pterosaurs from Brazil and England, such as Amblydectes, Anhanguera, Coloborhynchus, and Ornithocheirus.

Lonchodectidae Family of pteranodontoid pterosaurs

Lonchodectidae or Lonchodraconidae is a group of pterosaurs within the clade Pterodactyloidea. It has variously been considered to be within Ctenochasmatoidea, Azhdarchoidea and Pteranodontia. They are notable for their high, conical tooth sockets and raised alveolar margins.

Brook Brick Pit

Brook Brick Pit is a 0.9-hectare (2.2-acre) geological Site of Special Scientific Interest west of Wormley Surrey. It is a Geological Conservation Review site.

Ornithocheiridae Family of ornithocheiran pterosaurs

Ornithocheiridae is a group of pterosaurs within the suborder Pterodactyloidea. These pterosaurs were among the last to possess teeth. Members that belong to this group lived from the Early to Late Cretaceous periods, around 140 to 90 million years ago.

Istiodactylidae Family of istiodactyliform pterosaurs

Istiodactylidae is a small family of pterosaurs. This family was named in 2001 after the type genus Istiodactylus was discovered not to be a member of the genus Ornithodesmus.

<i>Volgadraco</i> Genus of ornithocheiroid pterosaur from the Late Cretaceous

Volgadraco is a genus of pterodactyloid pterosaur from the Upper Cretaceous of European Russia. Volgadraco was originally classified as an azhdarchid, however, recent studies have concluded that it may belong to either the family Nyctosauridae, or the family Pteranodontidae.

Vectis Formation

The Vectis Formation is a geological formation on the Isle of Wight and Swanage, England whose strata were formed in the lowermost Aptian, approximately 125 million years ago. The environment of deposition was that of a freshwater coastal lagoon with occasional marine influence after the early Aptian marine transgression, transitioning from the floodplain environment of the underlying Wessex Formation. The primary lithology is of laminated grey mudstones. The Vectis Formation is composed of three geological members: the Shepherds Chine member, the Barnes High Sandstone member, and the Cowleaze Chine member. It is overlain by the fully marine Atherfield Clay Formation, part of the Lower Greensand Group. Dinosaur remains are among the fossils that have been recovered from the formation.

Pterosaurs included the largest flying animals ever to have lived. They are a clade of prehistoric archosaurian reptiles closely related to dinosaurs. Species among pterosaurs occupied several types of environments, which ranged from aquatic to forested. Below is a list that comprises the largest pterosaurs known as of 2016.

Lower Greensand Group Geological unit

The Lower Greensand Group is a geological unit present across large areas of Southern England. It was deposited during the Aptian and Albian stages of the Early Cretaceous. It predominantly consists of sandstone and unconsolidated sand that were deposited in shallow marine conditions.

Speeton Clay Formation Early Cretaceous geological formation in Yorkshire, England

The Speeton Clay Formation (SpC) is a Lower Cretaceous geologic formation in Yorkshire, northern England. 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.

Boreopteridae Family of pteranodontoid pterosaurs

Boreopteridae is a group of pterodactyloid pterosaurs from the Aptian-age Lower Cretaceous Yixian Formation of Liaoning, China.

Pteranodontoidea Clade of ornithocheiroid pterosaurs from the Cretaceous period

Pteranodontoidea is an extinct clade of ornithocheiroid pterosaurs from the Early to Late Cretaceous of Asia, Africa, Europe, North America and South America. It was named by Alexander Wilhelm Armin Kellner in 1996. In 2003, Kellner defined the clade as a node-based taxon consisting of the last common ancestor of Anhanguera, Pteranodon and all its descendants. The clade Ornithocheiroidea is sometimes considered to be the senior synonym of Pteranodontoidea, however it depends on its definition. Brian Andres in his analyses, converts Ornithocheiroidea using the definition of Kellner (2003) to avoid this synonymy.

<i>Vectidraco</i> Genus of azhdarchoid pterosaur from the Early Cretaceous

Vectidraco, is a genus of azhdarchoid pterosaur from the Lower Cretaceous of England.

Ornithocheiromorpha Clade of pteranodontoid pterosaurs

Ornithocheiromorpha is a group of pterosaurs within the suborder Pterodactyloidea. Fossil remains of this group date back from the Early to Late Cretaceous periods, around 140 to 92.5 million years ago. Ornithocheiromorphs were discovered worldwide except Antarctica, though most genera were recovered in Europe, Asia and South America. They were the most diverse and successful pterosaurs during the Early Cretaceous, but throughout the Late Cretaceous they were replaced by better adapted and more advanced pterosaur species such the pteranodontids and azhdarchoids. The Ornithocheiromorpha was defined in 2014 by Andres and colleagues, and they made Ornithocheiromorpha the most inclusive clade containing Ornithocheirus, but not Pteranodon.

References

  1. "Atherfield Clay Formation". The BGS Lexicon of Named Rock Units. British Geological Survey. Archived from the original on 5 August 2008.
  2. Naish, D.; Simpson, M.; Dyke, G. (2013). Farke, Andrew A (ed.). "A New Small-Bodied Azhdarchoid Pterosaur from the Lower Cretaceous of England and Its Implications for Pterosaur Anatomy, Diversity and Phylogeny". PLOS ONE. 8 (3): e58451. Bibcode:2013PLoSO...858451N. doi: 10.1371/journal.pone.0058451 . PMC   3601094 . PMID   23526986.