Last updated
Age (Ma)
Paleogene Paleocene Danian younger
Cretaceous Upper/
Maastrichtian 66.072.1
Campanian 72.183.6
Santonian 83.686.3
Coniacian 86.389.8
Turonian 89.893.9
Cenomanian 93.9100.5
Albian 100.5~113.0
Aptian ~113.0~125.0
Barremian ~125.0~129.4
Hauterivian ~129.4~132.9
Valanginian ~132.9~139.8
Berriasian ~139.8~145.0
Jurassic Upper/
Tithonian older
Subdivision of the Cretaceous system
according to the ICS, as of 2017. [1]

The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous epoch, or a stage in the Upper Cretaceous series. It spans the time between 93.9 ± 0.8 Ma and 89.8 ± 1 Ma (million years ago). The Turonian is preceded by the Cenomanian stage and underlies the Coniacian stage. [2]

The International Commission on Stratigraphy (ICS), sometimes referred to by the unofficial name "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 scale.

A geologic age is a subdivision of geologic time that divides an epoch into smaller parts. A succession of rock strata laid down in a single age on the geologic timescale is a stage.

The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series. The Cretaceous is named after the white limestone known as chalk which occurs widely in northern France and is seen in the white cliffs of south-eastern England, and which dates from this time.


At the beginning of the Turonian an anoxic event took place which is called the Cenomanian-Turonian boundary event or the "Bonarelli Event".

Anoxic event Intervals in the Earths past where parts of oceans were depleted of oxygen at depth over a large geographic area

Oceanic anoxic events or anoxic events (anoxia conditions) were intervals in the Earth's past where portions of oceans become depleted in oxygen (O2) at depths over a large geographic area. During some of these events, euxinia, waters that contained H
hydrogen sulfide, developed. Although anoxic events have not happened for millions of years, the geological record shows that they happened many times in the past. Anoxic events coincided with several mass extinctions and may have contributed to them. These mass extinctions include some that geobiologists use as time markers in biostratigraphic dating. Many geologists believe oceanic anoxic events are strongly linked to slowing of ocean circulation, climatic warming, and elevated levels of greenhouse gases. Researchers have proposed enhanced volcanism (the release of CO2) as the "central external trigger for euxinia".

The Cenomanian-Turonian boundary event, or the Cenomanian-Turonian extinction event, the Cenomanian-Turonian anoxic event, and referred also as the Bonarelli Event, was one of two anoxic extinction events in the Cretaceous period. The OAE 2 occurred approximately 91.5 ± 8.6 Ma, though other estimates are given as 93-94 Ma. The Cenomanian-Turonian boundary has recently been refined to 93.9 ± 0.15 Ma There was a large carbon disturbance during this time period. However, apart from the carbon cycle disturbance, there were also large disturbances in the oxygen and sulfur cycles of the ocean.

Stratigraphic definition

Lithographic limestone from the Gerofit Formation (Turonian) north of Makhtesh Ramon, southern Israel; a variety of Jerusalem stone (meleke). Turonian Jerusalem Stone 031612.JPG
Lithographic limestone from the Gerofit Formation (Turonian) north of Makhtesh Ramon, southern Israel; a variety of Jerusalem stone (meleke).

The Turonian (French: Turonien) was defined by the French paleontologist Alcide d'Orbigny (1802–1857) in 1842. Orbigny named it after the French city of Tours in the region of Touraine (department Indre-et-Loire), which is the original type locality.

France Republic with mainland in Europe and numerous oversea territories

France, officially the French Republic, is a country whose territory consists of metropolitan France in Western Europe and several overseas regions and territories. The metropolitan area of France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean. It is bordered by Belgium, Luxembourg and Germany to the northeast, Switzerland and Italy to the east, and Andorra and Spain to the south. The overseas territories include French Guiana in South America and several islands in the Atlantic, Pacific and Indian oceans. The country's 18 integral regions span a combined area of 643,801 square kilometres (248,573 sq mi) and a total population of 67.3 million. France, a sovereign state, is a unitary semi-presidential republic with its capital in Paris, the country's largest city and main cultural and commercial centre. Other major urban areas include Lyon, Marseille, Toulouse, Bordeaux, Lille and Nice.

Alcide dOrbigny French scientist

Alcide Charles Victor Marie Dessalines d'Orbigny was a French naturalist who made major contributions in many areas, including zoology, palaeontology, geology, archaeology and anthropology.

Tours Prefecture and commune in Centre-Val de Loire, France

Tours is a city in the centre-west of France. It is the administrative centre of the Indre-et-Loire department and the largest city in the Centre-Val de Loire region of France. In 2012, the city of Tours had 134,978 inhabitants, and the population of the whole metropolitan area was 483,744.

The base of the Turonian stage is defined as the place where the ammonite species Wutinoceras devonense first appears in the stratigraphic column. The official reference profile (the GSSP) for the base of the Turonian is located in the Rock Canyon anticline near Pueblo, Colorado (United States, coordinates: 38° 16' 56" N, 104° 43' 39" W). [3]

Wutinoceras is a genus of now extinct nautiloid cephalopods of the Wutinoceratidae family. It exhibits orthoconic actinocerids with ventral siphuncles composed of broadly expanded segments.

Stratigraphic column

A stratigraphic column is a representation used in geology and its subfield of stratigraphy to describe the vertical location of rock units in a particular area. A typical stratigraphic column shows a sequence of sedimentary rocks, with the oldest rocks on the bottom and the youngest on top.

Pueblo, Colorado City in Colorado, United States

Pueblo is a home rule municipality that is the county seat and the most populous city of Pueblo County, Colorado, United States. The population was 106,595 in 2010 census, making it the 267th most populous city in the United States and the 9th largest in Colorado. Pueblo is the heart of the Pueblo Metropolitan Statistical Area totaling over 160,000 people and an important part of the Front Range Urban Corridor. As of 2014, Pueblo is the primary city of the Pueblo–Cañon City combined statistical area (CSA) totaling approximately 208,000 people, making it the 134th largest in the nation.

The top of the Turonian stage (the base of the Coniacian) is defined as the place in the stratigraphic column where the inoceramid bivalve species Cremnoceramus rotundatus first appears.

Inoceramidae family of molluscs (fossil)

Inoceramidae is an extinct family of clam-like bivalves. Fossils of inoceramids are found in marine sediments of Permian to latest Cretaceous in age. Inoceramids tended to live in upper bathyal and neritic environments..


The Turonian is sometimes subdivided in Lower/Early, Middle and Upper/Late substages or subages. In the Tethys domain, it contains the following ammonite biozones:

Tethys Ocean Mesozoic ocean between Gondwana and Laurasia

The Tethys Ocean, also called the Tethys Sea or the Neotethys, was an ocean during much of the Mesozoic Era located between the ancient continents of Gondwana and Laurasia, before the opening of the Indian and Atlantic oceans during the Cretaceous Period.


Biostratigraphic unit or biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa.

Other important index fossils are species of the inoceramid genus Inoceramus (I. schloenbachi, I. lamarcki and I. labiatus). Inoceramids are bivalve Mollusca related to today's mussels.



Ankylosaurs of the Turonian
Talarurus Dinosaurium, Talarurus plicatospineus 2.jpg
Bayan Shireh Formation, Mongolia


Avialans of the Turonian


Bissekty Formation, UzbekistanA mid-sized enantiornithine, perhaps 20–25 cm long in life
Ichthyornis Ichthyornis restoration.jpeg


Bissekty Formation, Uzbekistan


Turonian - Campanian Alberta and Saskatchewan, Canada; Alabama, Kansas, New Mexico and Texas, USA; Argentina; Central AsiaThe Cretaceous ecological equivalent of modern seabirds such as gulls, petrels, and skimmers. At 60 cm (2.0 ft), it was the size of a gull. Although the wings and breastbone are very modern in appearance (suggesting strong flight ability), the jaws retained numerous small, sharp teeth


Ceratopsia of the Turonian


Moreno Hill Formation, New Mexico, USAThe earliest-known ceratopsian to have eyebrow horns and the oldest-known ceratopsian from North America, appears to have been roughly 3 to 3.5 meters (9.8 to 11.5 ft) long and 1 meter (3.3 feet) tall at the hips.
Zuniceratops Zuniceratops BW.jpg


Crocodylomorpha of the Turonian


Baurusuchus Baurusuchus BW.jpg


Turonian to Santonian Adamantina Formation, São Paulo, BrazilA terrestrial Peirosaurid




Mammalia of the Turonian


Straight Cliffs Formation of Utah, US.Smaller than a mouse, thought to behave somewhat similar.


Ornithopoda of the Turonian


Cerro Lisandro Formation, Neuquén Province, Patagonia, ArgentinaA 2 metres (6.6 ft) long elasmarian
Anabisetia Anabisetia.jpg
Bactrosaurus Bactrosaurus.JPG
Jeyawati Jeyawati NT.jpg


Turonian to Coniacian Gobi Desert, Mongolia and ChinaWould have been 6 m (20 ft) long[1] and 2 m (6.6 ft) high when in the quadrupedal stance, and weighed 1,100–1,500 kg (2,400–3,300 lb). Like many hadrosaurs, it could switch between bipedal and quadrupedal stances, but unusually it had large spines protruding from the vertebrae.
Jeyawati Turonian Moreno Hill Formation, New MexicoA basal hadrosauroid


Turonian to early Coniacian Portezuelo Formation, ArgentinaA genus of basal iguanodont, a large bipedal herbivore


Cenomanian-Turonian Bajo Barreal Formation, Chubut, ArgentinaA hypsilophodontid or other basal ornithopod, Notohypsilophodon would have been a bipedal herbivore. Its size has not been estimated


Cenomanian-TuronianChinaA poorly known iguanodont


Plesiosauria of the Turonian


Ottawa County, Kansas Brachauchenius represents the last known occurrence of a pliosaur in North America.
Libonectes Libonectes BW.jpg
Polyptychodon Polyptychodon hudsDB2.jpg
Thililua Thililua BW.jpg


Britton Formation (Cedar Hill), Texas, USAA 7–14 m (23–46 ft) long creature, was very similar to the related Elasmosaurus. It had a compact body with a short tail and large flippers. Its small skull had long, forward-facing teeth ideal for catching slippery fish and squid that came together outside of its mouth when the mouth was closed, and was placed atop a very long neck.


MoroccoA genus of polycotylid plesiosaur


Carlile Shale, Russell County, Kansas

Polyptychodon hudsoni

Texas, USAA 10 metres (33 ft) long Brachaucheniin pliosaurid


High Atlas, MoroccoA genus of polycotylid plesiosaur, the estimated total length of Thililua is 5.5 to 6 metres.


Pterosaurs of the Turonian


Upper Chalk, Kent, England


Albian-Turonian Chalk Formation, Kent and Cambridge Greensand, England


Squamata of the Turonian


Arcadia Park Shale, Texas, USAA basal, small, plesiopedal mososauroid


Arcadia Park Shale, Texas, USAA basal, small, lightly built mosasaur


Sauropods of the Turonian



Theropods (non-avialan)

Theropods of the Turonian
Neuquén, Argentina
Giganotosaurus Giganotos Db.jpg
Nothronychus Nothronychus BW2.jpg
Khara Khutul, Mongolia
Bayan Shireh Formation of Mongolia
Rio Limay, Argentina
New Mexico, USA
Khan-Bogdsomona, Mongolia
Kyzylkum Desert, UzbekistanA small (250 kg) tyrannosauroid.
Bajo Barreal Formation, Chubut Province, Argentina

Related Research Articles

In the geological timescale, the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma. It is preceded by the Kimmeridgian and followed by the Berriasian stage.

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 and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian.

The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma. The Albian is preceded by the Aptian and followed by the Cenomanian.

In the geologic timescale, the Bajocian is an age and stage in the Middle Jurassic. It lasted from approximately 170.3 Ma to around 168.3 Ma. The Bajocian age succeeds the Aalenian age and precedes the Bathonian age.

In the geologic timescale the Bathonian is an age and stage of the Middle Jurassic. It lasted from approximately 168.3 Ma to around 166.1 Ma. The Bathonian age succeeds the Bajocian age and precedes the Callovian age.

In the geological timescale, the Berriasian is an age or stage of the Early Cretaceous. It is the oldest, or lowest, subdivision in the entire Cretaceous. It spanned the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma. The Berriasian succeeds the Tithonian and precedes the Valanginian.

In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma. The Valanginian stage succeeds the Berriasian stage of the Lower Cretaceous and precedes the Hauterivian stage of the Lower Cretaceous.

In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 166.1 ± 4.0 Ma and 163.5 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian.

The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous series. Campanian spans the time from 83.6 to 72.1 million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian.

The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous epoch or a stage in the Lower Cretaceous series. It spans the time between 132.9 ± 2 Ma and 129.4 ± 1.5 Ma. The Hauterivian is preceded by the Valanginian and succeeded by the Barremian.

The Coniacian is an age or stage in the geologic timescale. It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series and spans the time between 89.8 ± 1 Ma and 86.3 ± 0.7 Ma. The Coniacian is preceded by the Turonian and followed by the Santonian.

The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series. It spans the time between 86.3 ± 0.7 mya and 83.6 ± 0.7 mya. The Santonian is preceded by the Coniacian and is followed by the Campanian.

The Hettangian is the earliest age and lowest stage of the Jurassic period of the geologic timescale. It spans the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma. The Hettangian follows the Rhaetian and is followed by the Sinemurian.

In the geologic timescale, the Sinemurian is an age and stage in the Early or Lower Jurassic epoch or series. It spans the time between 199.3 ± 2 Ma and 190.8 ± 1.5 Ma. The Sinemurian is preceded by the Hettangian and is followed by the Pliensbachian.

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. The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian.

In the geologic timescale, the Kimmeridgian is an age or stage in the Late or Upper Jurassic epoch or series. It spans the time between 157.3 ± 1.0 Ma and 152.1 ± 0.9 Ma. The Kimmeridgian follows the Oxfordian and precedes the Tithonian.

The Ladinian is a stage and age in the Middle Triassic series or epoch. It spans the time between 242 Ma and ~237 Ma. The Ladinian was preceded by the Anisian and succeeded by the Carnian.

The Norian is a division of the Triassic geological period. It has the rank of an age (geochronology) or stage (chronostratigraphy). The Norian lasted from ~227 to 208.5 million years ago. It was preceded by the Carnian and succeeded by the Rhaetian.

<i>Watinoceras</i> genus of molluscs (fossil)

Watinoceras is a genus of acanthoceratid ammonite that lived during the early Turonian stage of the Late Cretaceous.


  1. http://www.stratigraphy.org/index.php/ics-chart-timescale
  2. See Gradstein et al. (2004) for a detailed description of the ICS' timescale
  3. The GSSP was established by Kennedy et al. (2005)