In the

geologic timescale The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronol ...

the Bathonian is an

age Age or AGE may refer to: Time and its effects * Age, the amount of time someone or something has been alive or has existed ** East Asian age reckoning, an Asian system of marking age starting at 1 * Ageing or aging, the process of becoming older ...

and stage of the

Middle Jurassic The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations co ...

. It lasted from approximately 168.3 Ma to around 166.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age.

Stratigraphic definitions

The Bathonian Stage takes its name from

Bath Bath may refer to: * Bathing, immersion in a fluid ** Bathtub, a large open container for water, in which a person may wash their body ** Public bathing, a public place where people bathe * Thermae, ancient Roman public bathing facilities Plac ...

, a

spa town A spa town is a resort town based on a mineral spa (a developed mineral spring). Patrons visit spas to "take the waters" for their purported health benefits. Thomas Guidott set up a medical practice in the English town of Bath in 1668. H ...

in England built on Jurassic

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

(the Latinized form of the town name is ''Bathonium''). The name was introduced in scientific literature by Belgian geologist d'Omalius d'Halloy in 1843. The original type locality was located near Bath. The French palaeontologist Alcide d'Orbigny was in 1852 the first to define the exact length of the stage. The base of the Bathonian is at the first appearance 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 living coleoids (i.e., octopuses, squid and cuttlefish) ...

species '' Parkinsonia (Gonolkites) convergens'' in the stratigraphic column. The global reference profile for the base of the Bathonian (a GSSP) was ratified as Ravin du Bès, Bas-Auran area, Alpes de Haute Provence, France in 2009. The top of the Bathonian (the base of the Callovian Stage) is at the first appearance of ammonite

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'' Kepplerites''. In the Tethys domain, the Bathonian contains eight ammonite biozones: *zone of '' Clydoniceras discus'' *zone of '' Hecticoceras retrocostatum'' *zone of '' Cadomites bremeri'' *zone of '' Morrisiceras morrisi'' *zone of '' Tulites subcontractus'' *zone of '' Procerites progracilis'' *zone of ''Procerites aurigerus'' *zone of '' Zigzagiceras zigzag'' Rocks of Bathonian age are well developed in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

: in the northwest and southwest oolite

s are characteristically associated with

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

-bearing, crinoidal and other varieties, and with some beds of clay. In the north and northeast,

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

, etc.,

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

s and ferruginous oolites prevail, some of the last being exploited for

iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...

. They occur also in the extreme north of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

and in the Arctic regions, Greenland, Franz Josef Land, etc.; in Africa, Algeria, Tanzania, Madagascar and near the

Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is t ...

(Enon Beds); in India,

Rajputana Rājputana, meaning "Land of the Rajputs", was a region in the Indian subcontinent that included mainly the present-day Indian state of Rajasthan, as well as parts of Madhya Pradesh and Gujarat, and some adjoining areas of Sindh in modern-day ...

and Gulf of Kutch, and in South America. That article further references A. de Lapparent, ''Traité de géologie'' (5th ed., 1906), vol ii. The well-known Caen stone of Normandy and "Hauptrogenstein" of

Swabia Swabia ; german: Schwaben , colloquially ''Schwabenland'' or ''Ländle''; archaic English also Suabia or Svebia is a cultural, historic and linguistic region in southwestern Germany. The name is ultimately derived from the medieval Duchy of ...

, as well as the "Eisenkalk" of northwest Germany, and "Klaus-Schichten" of the Austrian Alps, are of Bathonian age.

References

Notes

Literature

* ; 2004: ''A Geologic Time Scale 2004'', Cambridge University Press. * ; 1843: ''Précis élémentaire de géologie'', Bertrand, Paris.

External links

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