Bartonian
Encyclopedia
The Bartonian is, in the ICS
's geological timescale, a stage or age in the middle Eocene
epoch
or series
. The Bartonian age spans the time between and . It is preceded by the Lutetian
and is followed by the Priabonian
age.
stratigrapher Karl Mayer-Eymar in 1857. The name derives from the coastal village Barton-on-Sea (part of New Milton
) in southern England. The Barton Group, a lithostratigraphic
unit from the south English Hampshire Basin
, is of Bartonian age. The distinction between group
and stage was made in the second part of the 20th century, when stratigraphers saw the need to distinguish between litho- and chronostratigraphy
.
The base of the Bartonian is at the first appearance of the calcareous nannoplankton species Reticulofenestra reticulata. In 2009, an official reference profile (GSSP) for the base of the Bartonian had not yet been established.
The top of the Bartonian stage (the base of the Priabonian) is at the first appearance of calcareous nannoplankton species Chiasmolithus oamaruensis (which forms the base of nannoplankton biozone
NP18).
The Bartonian stage overlaps part of the upper Robiacian European Land Mammal Mega Zone (it spans the Mammal Paleogene zone 16), the upper Uintan
and Duchesnean
North American Land Mammal Ages
, part of the Divisaderan
South American Land Mammal Age
and is coeval with the Sharamururian Asian Land Mammal Age.
The Auversian regional stage of France is coeval with the Bartonian and is therefore no longer used.
.; 1857: Tableau synchronique des formations tertiaires d’Europe, 3rd ed., Zürich.
International Commission on Stratigraphy
The International Commission on Stratigraphy , sometimes referred to by the unofficial "International Stratigraphic Commission" is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphy, geological, and geochronological matters on a global...
's geological timescale, a stage or age in the middle Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
epoch
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...
or series
Series (stratigraphy)
Series are subdivisions of rock layers made based on the age of the rock and corresponding to the dating system unit called an epoch, both being formally defined international conventions of the geological timescale. A series is therefore a sequence of rock depositions defining a...
. The Bartonian age spans the time between and . It is preceded by the Lutetian
Lutetian
The Lutetian is, in the geologic timescale, a stage or age in the Eocene. It spans the time between and . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the Middle Eocene subepoch...
and is followed by the Priabonian
Priabonian
The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene epoch or series. It spans the time between and...
age.
Stratigraphic definition
The Bartonian stage was introduced by SwissSwitzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
stratigrapher Karl Mayer-Eymar in 1857. The name derives from the coastal village Barton-on-Sea (part of New Milton
New Milton
New Milton is a market town in south west Hampshire, England. The town has a high street and holds a market every Wednesday. Situated on the edge of the New Forest, the town is about 6 miles west of Lymington town centre and 12 miles east of Bournemouth town centre.-History:New Milton dates back...
) in southern England. The Barton Group, a lithostratigraphic
Lithostratigraphy
Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology...
unit from the south English Hampshire Basin
Hampshire Basin
The Hampshire Basin is a geological basin of Paleogene age in southern England, underlying parts of Hampshire, the Isle of Wight, Dorset, and Sussex...
, is of Bartonian age. The distinction between group
Group (stratigraphy)
A group in stratigraphy is a lithostratigraphic unit, a part of the geologic record or rock column that consists of defined rock strata. Groups are divided into formations and are sometimes themselves grouped into "supergroups"....
and stage was made in the second part of the 20th century, when stratigraphers saw the need to distinguish between litho- and chronostratigraphy
Chronostratigraphy
Chronostratigraphy is the branch of stratigraphy that studies the age of rock strata in relation to time.The ultimate aim of chronostratigraphy is to arrange the sequence of deposition and the time of deposition of all rocks within a geological region, and eventually, the entire geologic record of...
.
The base of the Bartonian is at the first appearance of the calcareous nannoplankton species Reticulofenestra reticulata. In 2009, an official reference profile (GSSP) for the base of the Bartonian had not yet been established.
The top of the Bartonian stage (the base of the Priabonian) is at the first appearance of calcareous nannoplankton species Chiasmolithus oamaruensis (which forms the base of nannoplankton biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....
NP18).
The Bartonian stage overlaps part of the upper Robiacian European Land Mammal Mega Zone (it spans the Mammal Paleogene zone 16), the upper Uintan
Uintan
The Uintan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 46,200,000 to 42,000,000 years BP lasting . It is usually considered to fall within the Eocene epoch...
and Duchesnean
Duchesnean
The Duchesnean North American Stage on the geologic timescale is a North American Land Mammal Age , with an age from 42 to 38 million years BP, representing . It falls within the Eocene epoch. The Duchesnean is preceded by the Uintan and followed by the Chadronian NALMA.The Duchesnean falls within...
North American Land Mammal Ages
North American Land Mammal Ages
The North American Mammal Ages establishes a geologic timescale for prehistoric North American fauna beginning 66.5 Ma during the Paleocene and continuing through to the Late Pleistocene...
, part of the Divisaderan
Divisaderan
The Divisaderan age is a period of geologic time within the Eocene epoch of the Paleogene used more specifically with South American Land Mammal Ages. It follows the Mustersan and precedes the Tinguirirican age....
South American Land Mammal Age
South American Land Mammal Age
The South American Mammal Ages establish a geologic timescale for prehistoric South American fauna beginning 64.5 Ma during the Paleogene and continuing through to the Middle Pleistocene...
and is coeval with the Sharamururian Asian Land Mammal Age.
The Auversian regional stage of France is coeval with the Bartonian and is therefore no longer used.
Literature
; 2004: A Geologic Time Scale 2004, Cambridge University PressCambridge University Press
Cambridge University Press is the publishing business of the University of Cambridge. Granted letters patent by Henry VIII in 1534, it is the world's oldest publishing house, and the second largest university press in the world...
.; 1857: Tableau synchronique des formations tertiaires d’Europe, 3rd ed., Zürich.
External links
- GeoWhen Database – Bartonian
- Paleogene timescale, at the website of the subcommission for stratigraphic information of the ICS
- Stratigraphic chart of the Paleogene, at the website of Norges Network of offshore records of geology and stratigraphy