Callovian: Wikis

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System Series Stage Age (Ma)
Cretaceous Lower Berriasian younger
Jurassic Upper Tithonian 145.5–150.8
Kimmeridgian 150.8–155.7
Oxfordian 155.7–161.2
Middle Callovian 161.2–164.7
Bathonian 164.7–167.7
Bajocian 167.7–171.6
Aalenian 171.6–175.6
Lower Toarcian 175.6–183.0
Pliensbachian 183.0–189.6
Sinemurian 189.6–196.5
Hettangian 196.5–199.6
Triassic Upper Rhaetian older
Subdivision of the Jurassic system according to the IUGS, as of July 2009.

In the geologic timescale, the Callovian is an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma (million years ago) and 161.2 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian.[1]

Contents

Stratigraphic definitions

The Callovian stage was first described by French palaeontologist Alcide d'Orbigny in 1852. Its name derives from the latinized name for Kellaways Bridge, a small hamlet 3 km north-east of Chippenham, Wiltshire, England.

The base of the Callovian is defined as the place in the stratigraphic column where the ammonite genus Kepplerites first appears, which is the base of the biozone of Macrocephalites herveyi. A global reference profiel (a GSSP) for the base had in 2009 not yet been assigned.

The top of the Callovian (the base of the Oxfordian) is at the first appearance of ammonite species Brightia thuouxensis.

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Subdivision

Matmor Formation (Callovian, Peltoceras athleta Zone) in Makhtesh Gadol, Israel.

The Callovian is often subdivided into three substages (or subages): Lower/Early, Middle and Upper/Late Callovian. In the Tethys domain, the Callovian encompasses six ammonite biozones:

  • zone of Quenstedtoceras lamberti
  • zone of Peltoceras athleta
  • zone of Erymnoceras coronatum
  • zone of Reineckeia anceps
  • zone of Macrocephalites gracilis
  • zone of Bullatimorphites bullatus

Palaeogeography

During the Callovian, Europe was an Archipelago of a dozen or so large islands. Between them were extensive areas of continental shelf. Consequently, there are shallow marine Callovian deposits in Russia and from Belarus, through Poland and Germany, into France and eastern Spain and much of England. Around the former island coasts are frequently, land-derived sediments. These are to be found, for example, in western Scotland.[2]

Palaeontology

Crocodylomorphs

Crocodylomorphs of the Callovian
Taxa Presence Location Description Images
Junggarsuchus The sphenosuchian Junggarsuchus was a small, ~1 meter long, Chinese predator.
A life restoration of a Metriorhynchus species.
Metriorhynchus An opportunistic carnivore that fed on fish, belemnites and other marine animals and possible carrion. Metriorhynchus grew to an average adult length of 3 meters (9.6 ft), although some individuals may have reached lengths rivaling those of large nile crocodiles.
Steneosaurus

Ornithischians

Ornithischia of the Callovian
Taxa Presence Location Description Images
Agilisaurus Dashanpu Formation, Sichuan, China A four-foot long bipedal herbivore that was built for speed. It was discovered in one of China's many Callovian deposits.
Callovosaurus England A primitive camptosaurid iguanodont, estimated to have been 3.5 meters long
Ferganocephale Kyrgyzstan Possibly an early pachycephalosaurid
Hexinlusaurus
Hexinlusaurus multidens
Bathonian to Callovian Lower Shaximiao Formation, Sichuan, China A small ornithischian dinosaur distinguished from all other basal ornithischians by a single autapomorphy, the presence of a marked concavity that extends over the lateral surface of the postorbital.

Plesiosaurs

Plesiosaurs of the Callovian
Taxa Presence Location Description Images
Liopleurodon
Liopleurodon was a large pliosaur from the Callovian stage.
Pachycostasaurus
Peloneustes
Pliosaurus
Simolestes
Simolestes vorax

Sauropods

Sauropods of the Callovian
Taxa Presence Location Description Images
Abrosaurus Abrosaurus was a small (30 foot adult length) sauropod from China with an unusual skull.
Atlasaurus
Ferganasaurus
Ferganasaurus verzilini
A Kyrgistani sauropod genus that resembled Rhoetosaurus.
Patagosaurus

Stegosauria

Stegosaurs of the Callovian
Taxa Presence Location Description Images
Huayangosaurus Bathonian to Callovian Lower Shaximiao Formation, Sichuan, China A 4.5 meters in length quadrupedal herbivore with a small skull and a spiked tail. Bore the distinctive double row of plates, rising vertically along its arched back, of all the stegosaurians and two pairs of long spikes extending horizontally near the end of its tail
Lexovisaurus Lisieux, France; Northern England Traditionally, Lexovisaurus was depicted as having either large spines over the hips or shoulders, with a selection of flat plates and round pointed spines that ran along the back and tail. It was probably about 5 m long.
Loricatosaurus France; England Known from remains previously assigned to Lexovisaurus.

Theropods

theropods of the Callovian
Taxa Presence Location Description Images
Eustreptospondylus A moderately large (17-23 feet long) predatory dinosaur that was closely related to Megalosaurus.
Gasosaurus
Gasosaurus constructus
An 11-13 foot predator from China whose discovery was assisted by the petroleum industry.
Pedopenna
Szechuanoraptor A Chinese theropod that has yet to be formally described.

Ammonitida

Members of the Order Ammonitida are known as ammonitic ammonites. They are distinguished primarily by their suture lines. In ammonitic suture patterns, the lobes and saddles are much subdivided (fluted) and subdivisions are usually rounded instead of saw-toothed. Ammonoids of this type are the most important species from a biostratigraphical point of view. This suture type is characteristic of Jurassic and Cretaceous ammonoids but extends back all the way to the Permian.

Ammonites of the Callovian
Taxa Presence Location Description Images
Cadomites
Peltoceras solidum ammonite from the Matmor Formation (Jurassic, Callovian) in Makhtesh Gadol, Israel.
Oecoptychius
Oecotraustes
Oxycerites
Peltoceras

Belemnites

Belemnites of the Callovian
Taxa Presence Location Description Images
Produvalia
Callovian belemnite from the Zohar Formation, northern Israel

Nautiloids

Nautiloids of the Callovian
Taxa Presence Location Description Images
Somalinautilus
An illustration of a variety of fossil nautiloids.

Neocoleoids

Neocoleoids of the Callovian
Taxa Presence Location Description Images
Proteroctopus
Proteroctopus ribeti
Pyritized fossil of Vampyronassa rhodanica from Voulte-sur-Rhône, France.
Rhomboteuthis
Rhomboteuthis lehmani
A squid species discovered in France.
Vampyronassa
Vampyronassa rhodanica

References

Notes

  1. ^ See for a detailed geologic timescale Gradstein et al. (2004)
  2. ^ Elmi & Babin fig.55.

Literature

  • Elmi, S. & Babin, C.; 2002: Histoire de la Terre, Dunod, Paris (2nd ed.), ISBN 2 10 006631 5. (French)
  • Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.
  • d'Orbigny, A.C.V.M.D.; 1842: Paléontologie française. 1. Terrains oolitiques ou jurassiques. 642 p, Bertrand, Paris. (French)

External links

Jurassic period
Lower/Early Jurassic Middle Jurassic Upper/Late Jurassic
Hettangian | Sinemurian
Pliensbachian | Toarcian
Aalenian | Bajocian
Bathonian | Callovian
Oxfordian | Kimmeridgian
Tithonian

1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

CALLOVIAN (from Callovium, the Latinized form of Kellaways, a village not far from Chippenham in Wiltshire),,in geology, the name introduced by d'Orbigny for the strata which constitute the base of the Oxfordian or lowermost stage of the Middle Oolites. The term used by d'Orbigny in 1844 was "Kellovien," subsequently altered to "Callovien" in 1849; William Smith wrote "Kellaways" or "Kelloways Stone" towards the close of the 18th century. In England it is now usual to speak of the Kellaways Beds; these comprise (t) the Kellaways Rock, alternating clays and sands with frequent but irregular concretionary calcareous sandstones, with abundant fossils; and (2) a lower division, the Kellaways Clay, which often contains much selenite but is poor in fossils. The lithological characters are impersistent, and the sandy phase encroaches sometimes more, sometimes less, upon the true Oxford Clay. The rocks may be traced from Wiltshire into Bedfordshire, Lincolnshire and Yorkshire, where they are well exposed in the cliffs at Scarborough and Gristhorpe, at Hackness (90 ft.), Newtondale (80 ft.) and Kepwick (loo ft.). In Yorkshire, however, the Callovian rocks lie upon a somewhat higher palaeontological horizon than in Wiltshire. In England, Kepplerites calloviensis is taken as the zone fossil; other common forms are Cosmoceras modiolare, C. gowerianum, Belemnites oweni, Ancyloceras calloviense, Nautilus calloviensis, Avicula oxalis, Gryphaea bilobata, &c.

On the European continent the "Callovien" stage is used in a sense that is not exactly synonymous with the English Callovian; it is employed to embrace beds that lie both higher and lower in the time-scale. Thus, the continental Callovien includes the following zones:-- Upper Callovien Zone of Peltoceras athleta, Cosmoceras Duncani, (Divesien) Quenstedtoceras Lamberti and Q. rnariae. Zone of Reineckia anceps, Stephanoceras coronatum and Cosmoceras jason and a lower zone of C. gowerianum and Macrocephalites macrocephalus. Rocks of Callovian age (according to the continental classification) are widely spread in Europe, which, with the exception of numerous insular masses, was covered by the Callovian Sea. The largest of these land areas lay over Scandinavia and Finland, and extended eastward as far as the 40th meridian. In arctic regions these rocks have been discovered in Spitzbergen, Franz Josef Land, the east coast of Greenland, and Siberia. They occur in the Hebrides and Skye and in England as indicated above. In France they are well exposed on the coast of Calvados between Trouville and Dives, where the marls and clays are 200 ft. thick. In the Ardennes clays bearing pyrites and oolitic limonite are about 30 ft. thick. Around Poitiers the Callovian is too ft. thick, but the formation thins in the direction of the Jura.

Clays and shales with ferruginous oolites represent the Callovian of Germany; while in Russia the deposits of this age are mainly argillaceous. In North America Callovian fossils are found in California; in South America in Bolivia. In Africa they have been found in Algeria and Morocco, in Somaliland and Zanzibar, and on the west coast of Madagascar. In India they are Lower Callovien represented by the shales and limestones of the Chari series of Cutch. Callovian rocks are also recorded from New Guinea and the Moluccas.

See JURASSIC; also A. de Lapparent, Traite de ge'ologie, vol. ii. (5th ed., 1906), and H. B. Woodward, "The Jurassic Rocks of Britain," Mem. Geol. Survey, vol. v. (J. A. H.)


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