Close menu

Oxfordian (stage)


Source: http://en.wikipedia.org/wiki/Oxfordian_(stage)
Updated: 2017-07-11T16:32Z
System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
CretaceousLower/
Early
Berriasianyounger
JurassicUpper/
Late
Tithonian145.0–152.1
Kimmeridgian152.1–157.3
Oxfordian157.3–163.5
Mid/
Middle
Callovian163.5–166.1
Bathonian166.1–168.3
Bajocian168.3–170.3
Aalenian170.3–174.1
Lower/
Early
Toarcian174.1–182.7
Pliensbachian182.7–190.8
Sinemurian190.8–199.3
Hettangian199.3–201.3
TriassicUpper/
Late
Rhaetianolder
Subdivision of the Jurassic system
according to the IUGS, as of July 2012.

The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic epoch, or the lowest stage of the Upper Jurassic series. It spans the time between 163.5 ± 4 Ma and 157.3 ± 4 Ma (million years ago). The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian.[1]

Stratigraphic definitions

Cyclically alternating limestone (light, more competent) and marl/clay layers of Oxfordian age at Péry-Reuchenette, near Tavannes, Jura Mountains, Switzerland.

The Oxfordian stage was introduced into scientific writing by Alexandre Brongniart in 1827. The stage takes its name from the city of Oxford in England.

The base of the Oxfordian stage is defined as the point in the stratigraphic record where the ammonite species Brightia thuouxensis first appears. A global reference profile for the base (a GSSP) had in 2009 not yet been assigned. The top of the Oxfordian stage (the base of the Kimmeridgian) is at the first appearance of ammonite species Pictonia baylei.

In the Tethys domain, the Oxfordian contains six ammonite biozones:

Palaeontology

†Sauropods

Sauropods of the Oxfordian
TaxaPresenceLocationDescriptionImages
Bathonian-OxfordianOriginally thought to have lived form the Hauterivian to Barremian.

†Ornithischians

Ornithischians of the Oxfordian
TaxaPresenceLocationDescriptionImages
Oxfordian? Tithonian?Chaoyang, Liaoning, ChinaA marginocephalian dinosaur from the Late Jurassic of China, belonged to the Ceratopsia, a group of primarily herbivorous dinosaurs with parrot-like beaks
Chaoyangsaurus
Chialingosaurus
Chungkingosaurus
Dacentrurus
Tuojiangosaurus
Yinlong
Upper Shaximiao Formation, Sichuan, ChinaA genus of stegosaur similar to Kentrosaurus
Upper Shaximiao Formation, Sichuan, ChinaOne of the smallest of the stegosaurids at 3–4 metres long (10–13 ft), Chungkingosaurus had at least five spikes on its thagomizer. It had a rather high and narrow skull and large, thick bony plates.
England, France, Spain, PortugalA large stegosaurid
Dashanpu Formation, Sichuan, ChinaBy extrapolation from the remains of possible species and other basal ornithopods, it was a herbivorous bipedal animal around 1.3 to 1.5 meters (4.3 to 4.9 ft) long. It would have been a strong runner
Junggar Basin, Xinjiang, ChinaA genus of stegosaurid
Upper Shaximiao Formation, Sichuan, ChinaThe best understood of the Chinese stegosaurs. It was around 7.0 meters (23.0 feet) long and 2 meters (6.6 feet) high, with a postulated weight of around 4 metric tons (4.4 short tons).
Shishugou Formation, Xinjiang, ChinaA small, primarily bipedal herbivore, approximately 1.2 meters (3.9 feet) long, the oldest and most primitive ceratopsian known to science.

†Plesiosaurians

Plesiosaurians of the Oxfordian
TaxaPresenceLocationDescriptionImages
Bajocian-Tithonian

†Thalattosuchians

Thalattosuchians of the Oxfordian
TaxaPresenceLocationDescriptionImages
Metriorhynchus, a marine crocodilian.
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 (9.8 feet), although some individuals may have reached lengths rivaling those of large nile crocodiles.

Theropods

Theropoda of the Oxfordian
TaxaPresenceLocationDescriptionImages
Bathonian-OxfordianOriginally thought to have lived form the Hauterivian to Barremian.
Yangchuanosaurus
Upper Shaximiao Formation, ChinaMonolophosaurus was a medium-sized predator that grew to at least 5.7 meters (19 feet) long. It had an odd, unique crest on its head which ran most of the length of the skull.
Franceone of the first dinosaurs collected and was the first described, though not named.
Upper Shaximiao Formation, Sichuan, ChinaYangchuanosaurus shangyouensis reached about 7 meters (23 feet) long with a skull around 80 cm (31 in) long. Its relative Y. magnus grew larger still: up to 10 meters (33 feet) long with a skull up to 1 metre (3.3 feet) in length. There was a bony knob on its nose and multiple hornlets and ridges, similar to Ceratosaurus. It had a massive tail that was about half its length.

Cephalopods

Cephalopods of the Oxfordian
TaxaPresenceLocationDescriptionImages
Belemnite fossils
An illustration of a variety of fossil nautiloids.

References

Notes

  1. ^ For a detailed geologic timescale see Gradstein et al. (2004)

Literature

  • Brongniart, A.; 1829: Tableau théorique de la succession et de la disposition la plus générale on Europa, des terrains et roches, qui composent l'écorce de la terre, Paris.(in French)
  • Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.

External links

Jurassic Period
Lower/Early JurassicMiddle JurassicUpper/Late Jurassic
Hettangian | Sinemurian
Pliensbachian | Toarcian
Aalenian | Bajocian
Bathonian | Callovian
Oxfordian | Kimmeridgian
Tithonian
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

Also On Wow

    Advertisement

    Trending Now