The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 190.8 ± 1.5 Ma and 182.7 ± 1.5 Ma (million years ago). The Pliensbachian is preceded by the Sinemurian and followed by the

Toarcian The Toarcian is, in the ICS' geologic timescale, an age and stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian. The Toarc ...

. The Pliensbachian ended with the extinction event called the

Toarcian turnover The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

. During the Pliensbachian, the middle part of the Lias was deposited in Europe. The Pliensbachian is roughly coeval with the Charmouthian regional stage of North America.

Stratigraphic definitions

The Pliensbachian takes its name from the hamlet of Pliensbach in the community of Zell unter Aichelberg in the Swabian Alb, some 30 km east of Stuttgart in

Germany Germany, officially the Federal Republic of Germany (FRG),, is a country in Central Europe. It is the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the sou ...

. The name was introduced into scientific literature by German palaeontologist Albert Oppel in 1858. The base of the Pliensbachian is at the first appearances of the ammonite species '' Bifericeras donovani'' and genera '' Apoderoceras'' and '' Gleviceras''. The Wine Haven profile near Robin Hood's Bay (

Yorkshire Yorkshire ( ; abbreviated Yorks), formally known as the County of York, is a historic county in northern England and by far the largest in the United Kingdom. Because of its large area in comparison with other English counties, functions have ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

) has been appointed as global reference profile for the base ( GSSP).Meister ''et al.'' (2006) The top of the Pliensbachian (the base of the Toarcian Stage) is at the first appearance of ammonite genus '' Eodactylites''.

Biostratigraphy

The Pliensbachian contains five ammonite biozones in the

boreal domain Boreal may refer to: Climatology and geography *Boreal (age), the first climatic phase of the Blytt-Sernander sequence of northern Europe, during the Holocene epoch *Boreal climate, a climate characterized by long winters and short, cool to mild ...

: *zone of ''

Pleuroceras spinatum ''Pleuroceras spinatum'' is a species of ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to l ...

'' *zone of '' Amaltheus margaritatus'' *zone of '' Prodactylioceras davoei'' *zone of '' Tragophylloceras ibex'' *zone of '' Uptonia jamesoni'' In the Tethys domain, the Pliensbachian contains six biozones: *zone of '' Emaciaticeras emaciatum'' *zone of '' Arieticeras algovianum'' *zone of '' Fuciniceras lavinianum'' *zone of ''Prodactylioceras davoei'' *zone of ''Tragophylloceras ibex'' *zone of ''Uptonia jamesoni''

References

Notes

Literature

*; 2004: ''A Geologic Time Scale 2004'',

Cambridge University Press Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press in the world. It is also the King's Printer. Cambr ...

. *; 2002: ''The Lower Lias of Robin Hood's Bay, Yorkshire, and the work of Leslie Bairstow'', Bulletin of the Natural History Museum. Geology Series 58, p. 81–152, Cambridge University Press, The Natural History Museum,
abstract
*; 2006: ''The Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic), Wine Haven, Yorkshire, UK'', Episodes 29(2), pp. 93–106. *; 1856-1858: ''Die Juraformation Englands, Frankreichs und des südwestlichen Deutschlands: nach ihren einzelnen Gliedern engetheilt und verglichen'', 857 pp., Ebner & Seubert, Stuttgart.

External links

Lower Jurassic timescale
at the website of the subcommission for stratigraphic information of the ICS
Stratigraphic chart of the Lower Jurassic
at the website of Norges Network of offshore records of geology and stratigraphy {{Geological history, p, m *03 Geological ages