The Serravallian is, 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 geochron ...

, an

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

or a stage in the middle

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

Epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided b ...

Series Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used i ...

, which spans the time between 13.82 Ma and 11.63 Ma (million years ago). The Serravallian follows the

Langhian The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene Epoch/Series. It spans the time between 15.97 ± 0.05 Ma and 13.65 ± 0.05 Ma (million years ago) during the Middle Miocene.GeoWhen (2007) The Langhian was ...

and is followed by the

Tortonian The Tortonian is in the geologic time scale an age or stage of the late Miocene that spans the time between 11.608 ± 0.005 Ma and 7.246 ± 0.005 Ma (million years ago). It follows the Serravallian and is followed by the Messinian. The Tort ...

. It overlaps with the middle of the

Astaracian The Astaracian age is a period of geologic time (), equivalent with the Middle Miocene and used more specifically with European Land Mammal Ages. It precedes the Vallesian age and follows the Orleanian age. The Astaracian overlaps the Langhian a ...

European Land Mammal Mega Zone The European Land Mammal Mega Zones (abbreviation: ELMMZ, more commonly known as European land mammal ages or ELMA) are zones in rock layers that have a specific assemblage of fossils ( biozones) based on occurrences of fossil assemblages of Europ ...

, the upper

Barstovian The Barstovian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 16,300,000 to 13,600,000 years BP, a period of . It is usua ...

and lower

Clarendonian The Clarendonian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 13,600,000 to 9,000,000 years BP, a period of . It is us ...

North American Land Mammal Ages The North American land mammal ages (NALMA) establishes a geologic timescale for North American fauna beginning during the Late Cretaceous and continuing through to the present. These periods are referred to as ages or intervals (or stages when ref ...

and the

Laventan The Laventan () age is a period of geologic time (13.8 to 11.8 Ma) within the Middle Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Colloncuran and precedes the Mayoan age. ...

and lower

Mayoan The Mayoan () age is a period of geologic time from 11.8 to 10 Ma, within the Middle to Late Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Laventan and precedes the Chasico ...

South American Land Mammal Ages The South American land mammal ages (SALMA) establish a geologic timescale for prehistoric South American fauna beginning 64.5 Ma during the Paleocene and continuing through to the Late Pleistocene (0.011 Ma). These periods are referred to as age ...

. It is also coeval with the Sarmatian and upper Badenian Stages of the

Paratethys The Paratethys sea, Paratethys ocean, Paratethys realm or just Paratethys (meaning "beside Tethys"), was a large shallow inland sea that covered much of mainland Europe and parts of western Asia during the middle to late Cenozoic, from the lat ...

time scale of Central and eastern Europe.

Definition

The Serravallian Stage was introduced in stratigraphy by the

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, a Romance ethnic group related to or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance languag ...

geologist

Lorenzo Pareto Lorenzo Nicolò Pareto (Genoa, 6 December 1800 – Genoa, 19 June 1865) was an Italian geologist and statesman. As a man of science, he is considered one of the fathers of modern geology. A member of the Italian National Academy of Sciences, h ...

in 1865. It was named after the town of

Serravalle Scrivia Serravalle Scrivia is a ''comune'' (municipality) in the Province of Alessandria in the Italian region of Piedmont, located about southeast of Turin and about southeast of Alessandria. Serravalle Scrivia borders the following municipalities: Ar ...

in northern Italy. The base of the Serravallian is at the first occurrence of fossils of the nanoplankton species '' Sphenolithus heteromorphus'' and is located in the chronozone C5ABr. The official

Global Boundary Stratotype Section and Point A Global Boundary Stratotype Section and Point (GSSP), sometimes referred to as a golden spike, is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. ...

(GSSP) for the Serravallian is in the 'Ras il-Pellegrin' section, located at the 'Ras il-Pellegrin' headland in the vicinity of 'Fomm ir-Rih' Bay, SW Malta.The base of the Serravallian is represented in the field as the formation boundary between the Globigerina Limestone formation and the Blue Clay formation. The base of the Serravallian is related to the Mi3b oxygen isotope excursion marking the onset of the Middle Miocene Cooling step. The top of the Serravallian (the base of the Tortonian Stage) is at the last common appearance of calcareous nanoplanktons '' Discoaster kugleri'' and planktonic foram '' Globigerinoides subquadratus''. It is also associated with the short normal-polarized chronozone C5r.2n.

Paleontology

Cartilaginous fish

Lamniformes The Lamniformes (, from Greek ''lamna'' "fish of prey") are an order (biology), order of sharks commonly known as mackerel sharks (which may also refer specifically to the family Lamnidae). It includes some of the most familiar species of sharks, ...

Otodontidae Otodontidae is an extinct family of sharks belonging to the order Lamniformes. Its members have been described as megatoothed sharks. They lived from the Early Cretaceous to the Pliocene, and included genera such as '' Otodus,'' including the gi ...

: †'' Otodus''

Birds

Anseriformes Anseriformes is an order (biology), order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest f ...

Anatidae The Anatidae are the biological family (biology), family of water birds that includes ducks, goose, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted f ...

: ''

Clangula The long-tailed duck (''Clangula hyemalis'') or coween, is a medium-sized sea duck that breeds in the tundra and taiga regions of the arctic and winters along the northern coastlines of the Atlantic and Pacific Oceans. It is the only member of ...

sp.''

Mammals

Primates Primates is an order of mammals, which is further divided into the strepsirrhines, which include lemurs, galagos, and lorisids; and the haplorhines, which include tarsiers and simians ( monkeys and apes). Primates arose 74–63 ...

Hominidae The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic Family (biology), family of primates that includes eight Neontology#Extant taxa versus extinct taxa, extant species in four Genus, genera: ''Orangutan ...

: †'' Anoiapithecus''.

Reptiles

Squamata Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest Order (biology), order of reptiles; most members of which are commonly known as Lizard, lizards, with the group also including Snake, snakes. With over 11,991 species, it i ...

Agamidae Agamidae is a family containing 582 species in 64 genera of iguanian lizards indigenous to Africa, Asia, Australia, and a few locations in Southern Europe. Many species are commonly called dragons or dragon lizards. Overview Phylogenetically ...

: '' Pogona'' and '' Diporiphora'' diverged from their last common ancestor during the Serravallian. *

Crocodylomorpha Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. Extinct crocodylomorphs were considerably mor ...

**The last known sebecid, '' Barinasuchus'', goes extinct about 11.8 mya. Thus ending the lineage of the notosuchians.

References

Notes

Literature

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

Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

Press. *; 1865: ''Note sur la subdivision que l'on pourrait etablir dans les terrains de l'Apennin septentrional'', Bulletin de la Société Géologique de France 2(22), p. 210-277.

External links

GeoWhen Database - SerravallianNeogene timescale
at the website of the subcommission for stratigraphic information of the ICS
Neogene timescale
at the website of the Norwegian network of offshore records of geology and stratigraphy {{Geological history, p, c *04 Miocene geochronology Geological ages