This is a list of official and unofficial names for time spans 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 ...

and units of

chronostratigraphy Chronostratigraphy is the branch of stratigraphy that studies the ages 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 geologica ...

. Since many of the smallest subdivisions of the geologic timescale were in the past defined on regional

lithostratigraphic Lithostratigraphy is a sub-discipline of stratigraphy, the geology, geological science associated with the study of stratum, strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are ...

units, there are many alternative names that overlap. The body concerned with standardizing the names of geochronologic units is the

International Commission on Stratigraphy The International Commission on Stratigraphy (ICS), sometimes referred to unofficially as the "International Stratigraphic Commission", is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigra ...

(ICS). In 2008 however, even though the

Phanerozoic The Phanerozoic Eon is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 538.8 million years to the present, and it began with the Cambrian Period, when anima ...

eon Eon or Eons may refer to: Time * Aeon, an indefinite long period of time * Eon (geology), a division of the geologic time scale Arts and entertainment Fictional characters * Eon, in the 2007 film ''Ben 10: Race Against Time'' * Eon, in the ...

is almost completely divided into internationally recognizable units, local subdivisions are often still preferred over the international ones.

List

, ,

West West or Occident is one of the four cardinal directions or points of the compass. It is the opposite direction from east and is the direction in which the Sunset, Sun sets on the Earth. Etymology The word "west" is a Germanic languages, German ...

, 1961 , - ,

Tiffanian The Tiffanian 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 60,200,000 to 56,800,000 years BP lasting . It is usually co ...

, 60.2 , 56.8 , age , Paleocene , North America , , Granger, 1917 , - ,

Tiglian The Tiglian, also referred to as the Tegelen, is a temperate complex stage in the glacial history of Northern Europe. It is preceded by the Praetiglian (stage). The stage was introduced by Zagwijn in 1957 based on geological formations in Tegelen i ...

, 2.40 , 1.80 , super-age , Pleistocene , Netherlands ,

Tegelen Tegelen ( li, Tegele) is a village in the municipality of Venlo, situated in the Netherlands. It was an independent municipality until 2001, when it was merged into the municipality of Venlo. Tiglian The name of the glacial stage of Tiglian (pa ...

(The Netherlands) , Dubois, 1905 , - ,

Tinguirirican The Tinguirirican ( es, Tinguiririquense) age is a period of geologic time (36.0–29.0 Ma) within the Late Eocene and Early Oligocene epochs of the Paleogene, used more specifically within the SALMA classification in South America. It follows th ...

, 36 , 29 , age , Oligo-Eocene , South America , , Flynn & Wyss, 2004 , - ,

Tithonian In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the K ...

, 150.8 ± 4.0 , 145.5 ± 4.0 , age , Jurassic , ICS , Tithon (

Greek mythology A major branch of classical mythology, Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the Cosmogony, origin and Cosmology#Metaphysical co ...

) , Oppel, 1865 , - ,

Tiupampan The Tiupampan ( es, Tiupampense) age is a period of geologic time (64.5–62.5 Ma) within the Paleocene epoch of the Paleogene used more specifically with South American land mammal ages (SALMA). It is the oldest SALMA age and precedes the Peligra ...

, 64.5 , 62.5 , age , Paleocene , South America , Tiupampa , Marshall & de Muizon, 1988 , - ,

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 Toarcian ...

, 183.0 ± 1.5 , 175.6 ± 2.0 , age , Jurassic , ICS ,

Thouars Thouars () is a commune in the Deux-Sèvres department in western France. On 1 January 2019, the former communes Mauzé-Thouarsais, Missé and Sainte-Radegonde were merged into Thouars. It is on the River Thouet. Its inhabitants are known as ...

(France) ,

d'Orbigny Alcide Charles Victor Marie Dessalines d'Orbigny (6 September 1802 – 30 June 1857) was a French naturalist who made major contributions in many areas, including zoology (including malacology), palaeontology, geology, archaeology and anthropol ...

, 1849 , - ,

Toyonian Cambrian Stage 4 is the still unnamed fourth stage of the Cambrian and the upper stage of Cambrian Series 2. It follows Cambrian Stage 3 and lies below the Wuliuan. The lower boundary has not been formally defined by the International Commission on ...

, 518.5 , 513.0 ± 2.0 , age , Cambrian , Russia, Kazakhstan , , Hill, 1964 , - ,

Tommotian Stage 2 of the Cambrian is the unnamed upper stage of the Terreneuvian Series. It lies atop the Fortunian and below Stage 3 of the Cambrian. It is commonly referred to as the Tommotian, after the Cambrian stratigraphy of Siberia. Neither the upper ...

, 534 , 530 , age , Cambrian , Russia, Kazakhstan , , Rozanov et al., 1966 , - , Tongaporutuan , 10.9 , 6.5 , age , Miocene , New Zealand , Tongaporutu, Taranaki Region , Fleming, 1959 , - , Tongrian , , , age , Oligocene , western Europe , , Dumont, 1839 , - ,

Tonian The Tonian (from grc, τόνος, tónos, meaning "stretch") is the first geologic period of the Neoproterozoic era (geology), Era. It lasted from to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined by t ...

, 1,000 , 850 , period , Proterozoic , ICS , , Cowie & Bassler, 1989 , - ,

Torrejonian The Torrejonian 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 63,300,000 to 60,200,000 years BP lasting . It is usually ...

, 63.3 , 60.2 , age , Paleocene , North America , , wood et al., 1941 , - ,

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 Torton ...

, 11.608 , 7.246 , age , Miocene , ICS ,

Tortona Tortona (; pms, Torton-a , ; lat, Dhertona) is a ''comune'' of Piemonte, in the Province of Alessandria, Italy. Tortona is sited on the right bank of the Scrivia between the plain of Marengo and the foothills of the Ligurian Apennines. History ...

(Italy) , Mayer-Eymar, 1858 , - , Totomian , 3.6 , 3.0 , age , Pliocene , Japan , , Ikebe, 1977 , - ,

Tournaisian The Tournaisian is in the ICS geologic timescale the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. The Tournaisian age lasted from Ma to Ma. It is preceded by the Famennian (the uppermost stage ...

, 359.2 ± 2.5 , 345.3 ± 2.1 , age , Carboniferous , ICS ,

Tournai Tournai or Tournay ( ; ; nl, Doornik ; pcd, Tornai; wa, Tornè ; la, Tornacum) is a city and municipality of Wallonia located in the province of Hainaut, Belgium. It lies southwest of Brussels on the river Scheldt. Tournai is part of Euromet ...

(Belgium) , Dumont, 1832 , - , Tozawan , 15.97 , 13.5 , age , Miocene , Japan , , Ikebe, 1977 , - , Treenean , 0.15 , 0.17 , chronozone , Pleistocene , Northwest Europe , , , - , Tremadoc(-ian) , 488.3 ± 1.7 , 478.6 ± 1.7 , epoch , Ordovician , ICS , Tremadoc Bay (Wales) , Sedgwick, 1846 , - ,

Trempealeauan The Trempealeauan is the upper or latest stage of the Upper or Late Cambrian in North America, spanning about 4 million years from about 492.5 to 488.3 m.y.a., equivalent to the Fengshanian of China. The name comes from the Trempealeau Formation, ...

, 492.5 , 488.3 ± 1.7 , age , Cambrian , North America , , , - ,

Trentonian ''The Trentonian'' is a daily newspaper serving Trenton, New Jersey, USA, and the surrounding Mercer County community. The paper in 2020 has a daily circulation of under 8,000 and a Sunday circulation under 7,000. As of August 2020, it was ranke ...

, , , age , Carboniferous , North America , , , - ,

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

, 251.0 ± 0.4 , 199.6 ± 0.6 , period , Mesozoic , ICS , ''threefold'' , Von Alberti, 1834 , - , Tubantian , 0.116 , 0.0115 , age , Pleistocene , Netherlands (obsolete) , , Van der Vlerk & Florschütz, 1950 , - ,

Turolian The Turolian age is a period of geologic time (9.0–5.3 Ma) within the Miocene used more specifically with European Land Mammal Ages. It precedes the Ruscinian age and follows the Vallesian age. The Turolian overlaps the Tortonian The Tortoni ...

, 8.7 , 4.9 , ELMMZ , Mio-Pliocene , Europe , ''Turolium'', Latin for

Teruel Teruel () is a city in Aragon, located in eastern Spain, and is also the capital of Teruel Province. It has a population of 35,675 in 2014 making it the least populated provincial capital in the country. It is noted for its harsh climate, with a ...

(Spain) , Crusafont, 1965 , - ,

Turonian 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 t ...

, 93.5 ± 0.8 , 89.3 ± 1.0 , age , Cretaceous , ICS ,

Tours Tours ( , ) is one of the largest cities in the region of Centre-Val de Loire, France. It is the Prefectures in France, prefecture of the Departments of France, department of Indre-et-Loire. The Communes of France, commune of Tours had 136,463 ...

(France) ,

, 1842 , - , Tuvalian , 222.5 , 217.4 ± 2.0 , sub-age , Triassic , Europe , , Mojsisovics, 1895 , - , Tyrrhenian , 0.26 , 0.01143 , sub-age , Pleistocene , Italy ,

Tyrrhenian Sea The Tyrrhenian Sea (; it, Mar Tirreno , french: Mer Tyrrhénienne , sc, Mare Tirrenu, co, Mari Tirrenu, scn, Mari Tirrenu, nap, Mare Tirreno) is part of the Mediterranean Sea off the western coast of Italy. It is named for the Tyrrhenian pe ...

, Issel, 1914 , - , Ufimian , 268 , 270,6 , age , Permian , obsolete , , Netxaev, 1915 , - ,

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 (NALMA), typically set from 46,200,000 to 42,000,000 years BP lasting . It falls within the ...

, 46.2 , 42.0 , age , Eocene , North America , , Wood et al., 1941 , - ,

Ulangochuian The Ulangochuian age is a period of geologic time (37.2–33.9 Ma) within the Late Eocene epoch of the Paleogene used more specifically with Asian Land Mammal Ages. It follows the Sharamurunian and precedes the Ergilian age. The Ulangochuian's upp ...

, 37.2 , 35.1 ,

ALMA Alma or ALMA may refer to: Arts and entertainment * ''Alma'' (film), a 2009 Spanish short animated film * ''Alma'' (Oswald de Andrade novel), 1922 * ''Alma'' (Le Clézio novel), 2017 * ''Alma'' (play), a 1996 drama by Joshua Sobol about Alma ...

, Eocene , Asia , , Li & Ting, 1983 , - , Ulatisian , 51 , 48 , age , Eocene , California , , Mallory, 1959 , - , Ulsterian , , , age , Devonian , North America , , Clarke & Schuchert, 1898 , - , Undillian , 506 , 504 , age , Cambrian , Australia , , Opik, 1979 , - ,

Uquian The Uquian age is a period of geologic time (3.0–1.5 Ma) within the Pliocene and Pleistocene epochs of the Neogene used more specifically with South American Land Mammal Ages. It follows the Montehermosan and precedes the Ensenadan The Ensenad ...

, 3.0 , 1.2 , age , Plio-Pleistocene , South America , Uquia (Argentina) , Castellanos, 1923 , - , Urutawan , 108.4 , 103.3 , age , Cretaceous , New Zealand , Urutawa Hill , Wellman, 1959 , - , Vaalian , 2,500 , 2,050 , age , Proterozoic , South Africa , , Kent & Hugh, 1978 , - ,

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 (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ...

, 140.2 ± 3.0 , 136.4 ± 2.0 , age , Cretaceous , ICS , Valangin (Switzerland) , Desor, 1853 , - ,

Vallesian The Vallesian age is a period of geologic time (11.6–9.0 Ma) within the Miocene used more specifically with European Land Mammal Ages. It precedes the Turolian age and follows the Astaracian age. The so-called Vallesian Crisis resulted in the e ...

, 11.1 , 8.7 , ELMMZ , Miocene , Europe , The

Vallès El Vallès (or simply Vallès) is a historical county in Catalonia, Spain, located in the center of the Catalan Pre-Coastal Range. It is nowadays represented by two separate administrative divisions ( ''comarques'') which are part of the Barcelon ...

(Spain) , Crusafont, 1950 , - ,

Vendian The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and the ...

, ~610 , 542.0 ± 1.0 , subera , Proterozoic , worldwide (obsolete) , , Murchison, 1835 , - , Venturian , 2.2 , 1.9 , age , Pleistocene , California , , Natland, 1953 , - , Vereiskian , 311.7 ± 1.1 , 309.2 , age , Carboniferous , Russia , , , - , Vierlandian , , , age , Miocene , Northern Germany , , , - , Vicksburgian , , , age , Oligocene , southern US , , Heilprin, 1882 , - ,

Villafranchian Villafranchian age ( ) is a period of geologic time (3.5–1.0 Ma) spanning the Late Pliocene and Early Pleistocene used more specifically with European Land Mammal Ages. Named by Italian geologist Lorenzo Pareto for a sequence of terrestrial s ...

, 3.5 , 1.1 , ELMMZ , Plio-Pleistocene , Europe , , Pareto, 1865 , - , Virgilian , , , age , Carboniferous , North America , , Moore, 1932 , - , Visean , 345.3 ± 2.1 , 326.4 ± 1.6 , age , Carboniferous , ICS ,

Visé Visé (; nl, Wezet, ; wa, Vizé) is a city and municipality of Wallonia, located on the river Meuse in the province of Liège, Belgium. The municipality consists of the following districts: Argenteau, Cheratte, Lanaye, Lixhe, Richelle, ...

(Belgium) , Dumont, 1832 , - , Vraconian , , , sub-age , Cretaceous , regional , , Renevier, 1867 , - , Waalian , 1.45 , 1.20 , super-age , Pleistocene , Netherlands , river

Waal WAAL (99.1 FM "The Whale") is a commercial radio station licensed to Binghamton, New York. It airs a classic rock radio format and is owned by Townsquare Media. WAAL is the oldest FM radio station in the Binghamton metropolitan area. It is an ...

, Zagwijn, 1960 , - ,

Waiauan While also using the international geologic time scale, many nations–especially those with isolated and therefore non-standard prehistories–use their own systems of dividing geologic time into epochs and faunal stages. In New Zealand, these epo ...

, 12.7 , 10.9 , age , Miocene , New Zealand , Waiau River, Southland Region , Fleming, 1959 , - ,

Waipawan While also using the international geologic time scale, many nations–especially those with isolated and therefore non-standard prehistories–use their own systems of dividing geologic time into epochs and faunal stages. In New Zealand, these epo ...

, 55.5 , 53.0 , age , Eocene , New Zealand ,

Waipawa Waipawa is the second-largest town in Central Hawke's Bay in the east of the North Island of New Zealand. It has a population of At the 2013 census, it had a population of 1,965, a change of 2.2 percent from the 2006 census. The town is locate ...

, Hornibrook & Harrington, 1957 , - , Waipipian , 3.60 , 3.00 , age , Pliocene , New Zealand , Waipipi , Fleming, 1953 , - ,

Waitakian While also using the international geologic time scale, many nations–especially those with isolated and therefore non-standard prehistories–use their own systems of dividing geologic time into epochs and faunal stages. In New Zealand, these epo ...

, 25.2 , 21.7 , age , Oligo-Miocene , New Zealand ,

Waitaki River The Waitaki River is a large braided river that drains the Mackenzie Basin and runs some south-east to enter the Pacific Ocean between Timaru and Oamaru on the east coast of the South Island of New Zealand. It starts at the confluence of the � ...

, Fleming, 1959 , - , Waitotaran , 3.8 , 3.1 , sub-age , Pliocene , New Zealand ,

Waitōtara River The Waitōtara River in New Zealand's North Island stretches approximately in length from its headwaters in the Matemateāonga Range to its mouth on the South Taranaki Bight. The river takes in significant tributaries such as the Ngutuwera, Mak ...

, Fleming, 1953 , - , Waltonian , , ~2.52 , age , Pliocene , Great Britain ,

Walton-on-the-Naze Walton-on-the-Naze is a seaside town on the North Sea coast and (as Walton le Soken) a former civil parish, now in the parish of Frinton and Walton, in the Tendring district in Essex, England. It is north of Clacton and south of the port of Ha ...

, Harmer,1900 , - ,

Wanganui Whanganui (; ), also spelled Wanganui, is a city in the Manawatū-Whanganui region of New Zealand. The city is located on the west coast of the North Island at the mouth of the Whanganui River, New Zealand's longest navigable waterway. Whangan ...

, 5.28 , present , epoch , Neogene-Quaternary , New Zealand ,

Whanganui Whanganui (; ), also spelled Wanganui, is a city in the Manawatū-Whanganui region of New Zealand. The city is located on the west coast of the North Island at the mouth of the Whanganui River, New Zealand's longest navigable waterway. Whangan ...

, Kingma, 1962 , - , Wangerripian , , , age , Paleo-Eocene , Australia , , Singleton, 1953 , - , Warendian , 485 , 478.6 , age , Ordovician , Australia , , Jones et al., 1971 , - , Warthian , 0.15 , 0.13 , chronozone , Pleistocene , Northwest Europe , , , - ,

Wasatchian The Wasatchian 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 55,400,000 to 50,300,000 years BP lasting . It is usually co ...

, 55.4 , 50.3 , age , Eocene , North America , , McGrew & Roehler, 1960 , - , Waucoban , , , epoch , Cambrian , North America , , Walcott, 1912 , - ,

Weichselian The Weichselian glaciation was the last glacial period and its associated glaciation in northern parts of Europe. In the Alpine region it corresponds to the Würm glaciation. It was characterized by a large ice sheet (the Fenno-Scandian ice sheet) ...

, 0.116 , 0.0115 , age , , Northern Europe , Weichsel, German name for the river

Vistula The Vistula (; pl, Wisła, ) is the longest river in Poland and the ninth-longest river in Europe, at in length. The drainage basin, reaching into three other nations, covers , of which is in Poland. The Vistula rises at Barania Góra in ...

(Poland) , Keilhack, 1926 , - , Wenlock(-ian) , 428.2 ± 2.3 , 422.9 ± 2.5 , epoch , Silurian , ICS ,

Much Wenlock Much Wenlock is a market town and parish in Shropshire, England, situated on the A458 road between Shrewsbury and Bridgnorth. Nearby, to the northeast, is the Ironbridge Gorge, and the new town of Telford. The civil parish includes the villag ...

(England) , Murchison, 1833 , - , Werrikooian , 1.00 , 1.806 , age , Pleistocene , Australia , , Hall & Pritchard, 1902 , - , Westphalian , 313.0 , 303.9 , age , Carboniferous , Europe ,

Westphalia Westphalia (; german: Westfalen ; nds, Westfalen ) is a region of northwestern Germany and one of the three historic parts of the state of North Rhine-Westphalia. It has an area of and 7.9 million inhabitants. The territory of the regio ...

(Germany) , de Lapparent & Munier-Chalmas, 1892 , - , Whaingaroan , 34.3 , 27.3 , age , Oligocene , New Zealand ,

Whaingaroa Whaingaroa may refer to: * Ngāpuhi / Ngāti Kahu ki Whaingaroa, a Māori tribe * Raglan, New Zealand, a town in Waikato See also * Whangaroa, an area in Northland, New Zealand * Whangaroa Harbour Whangaroa Harbour (; ), previously spelled ...

, Waikato Region , Finlay & Marwick, 1947 , - , Wheelerian , 1.9 , 0.01143 , age , Pleistocene , California , , Natland, 1953 , - ,

Whiterockian The Whiterockian, often referred to simply as the Whiterock, is an earliest or lowermost stage of the Middle Ordovician. Although the Whiterockian or Whiterock Stage refers mainly to the early Middle Ordovician in North America, it is often used in ...

, 471.8 ± 1.6 , 462 , age , Ordovician , North America , , Cooper, 1956 , - , Whitlandian , 475 , 473.5 , age , Ordovician , Europe ,

Whitland Whitland (Welsh: , lit. "Old White House", or ''Hendy-gwyn ar Daf'', "Old White House on the River Tâf", from the medieval ''Ty Gwyn ar Daf'') is both a town and a community in Carmarthenshire, Wales. Description The Whitland community is ...

(Wales) , Owens & Fortey, 1987 , - ,

Whitneyan The Whitneyan 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 33,300,000 to 30,800,000 years BP, a period of . It is usual ...

, 33.3 , 30.8 , age , Oligocene , North America , , Wood, 1937 , - , Whitwellian , 426.2 ± 2.4 , 425.4 , age , Silurian , regional , Whitwell Coppice (England) , Bassett et al., 1975 , - ,

Wisconsinan The Wisconsin Glacial Episode, also called the Wisconsin glaciation, was the most recent glacial period of the North American ice sheet complex. This advance included the Cordilleran Ice Sheet, which nucleated in the northern North American Cor ...

, 0.075 , 0.01 , age , Pleistocene , North America , , Geikie, 1894 , - ,

Wolfcampian The Cisuralian is the first Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian (geology), Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the w ...

, , , age , Permian , North America , , Udden, 1917 , - ,

Wolstonian The Wolstonian Stage is a middle Pleistocene stage of the geological history of Earth from approximately 374,000 until 130,000 years ago. It precedes the Eemian Stage in Europe and follows the Hoxnian Stage in the British Isles. It is also appro ...

, 0.238 , 0.128 , age , Pleistocene , Great Britain ,

Wolston Wolston is a village and civil parishes in England, civil parish in the Rugby (borough), Rugby borough of Warwickshire, England. The village is located roughly halfway between Rugby, Warwickshire, Rugby and Coventry, and had a population of 2,69 ...

(England) , West & Donner, 1956 , - , Woodbinian , , , age , Cretaceous , Gulf and Atlantic coast of the US , , Murray, 1961 , - ,

Wordian In the geologic timescale, the Wordian is an age or stage of the Permian. It is the middle of three subdivisions of the Guadalupian Epoch or Series. The Wordian lasted between and million years ago (Ma). It was preceded by the Roadian and foll ...

, 268.0 ± 0.7 , 265.8 ± 0.7 , age , Permian , ICS , , Udden, 1916 , - , Wuchenghuangtuan , 2.4 , 1.2 , age , Pleistocene , China , , , - ,

Wuchiapingian In the geologic timescale, the Wuchiapingian or Wujiapingian (from in the Liangshan area of Hanzhong, Shaanxi Province) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian Epoch or Series. The ...

, 260.4 ± 0.7 , 253.8 ± 0.7 , age , Permian , ICS , , Kaimera & Nakazawa, 1973 heng, 1962, - , Würm Glacial , 0.116 , 0.0115 , age , Pleistocene , Alps , river

Würm The Würm is a river in Bavaria, Germany, right tributary of the Amper. The length of the river is , or including the ''Steinbach'', the main feed of Lake Starnberg. It drains the overflow from Lake Starnberg and flows swiftly through the villag ...

(Germany) , Penck & Bruckner, 1909 , - , Wutaian , 2,600 , 2,350 , age , Archaean-Proterozoic , China , , Zhang, 1951 , - , Xiaodushanian , , 299 , age , Carboniferous , China , , zhou et al., 1987 , - , Xiushanian , 429 , 425.5 , age , Silurian , China , , Ge, 1980 , - , Yanguan , 349.5 , 345 , age , Carboniferous , China , , , - , Yarmouthian , 0.26 , 0.17 , age , Pleistocene , North America ,

Aegean Sea The Aegean Sea ; tr, Ege Denizi (Greek language, Greek: Αιγαίο Πέλαγος: "Egéo Pélagos", Turkish language, Turkish: "Ege Denizi" or "Adalar Denizi") is an elongated embayment of the Mediterranean Sea between Europe and Asia. It ...

, Leverett, 1898 , - , Yatalan , 3.4 , 2.0 , age , Plio-Pleistocene , Australia , , Ludbrook, 1963 , - , Yeadonian , 315.5 , 314.5 , age , Carboniferous , regional , Yeadon (England) , Hudson, 1945 , - ,

Younger Dryas The Younger Dryas (c. 12,900 to 11,700 years BP) was a return to glacial conditions which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM, c. 27,000 to 20,000 years BP). The Younger Dryas was the last stage ...

, 12,700 BP , 11,560 BP , chron , Weichselian , Northern Europe , ''

Dryas octopetala ''Dryas octopetala'', the mountain avens, eightpetal mountain-avens, white dryas or white dryad, is an Arctic–alpine flowering plant in the family Rosaceae. It is a small prostrate evergreen subshrub forming large colonies. The specific epithet ...

'' (plant) , , - , Ypeenian , 470 , 468.1 , age , Ordovician , Australia , , , - ,

Ypresian In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

, 55.8 ± 0.2 , 48.6 ± 0.2 , age , Eocene , ICS , ''Ypres'', French name for
Ieper () in Belgium , Dumont, 1849 , - , Ynezian , 61.5 , 55.8 , age , Paleocene , California , , Mallory, 1959 , - , Yuian , 9.5 , 3.6 , age , Plio-Miocene , Japan , , Ikebe, 1977 , - , Yurmatian , 1,375 , 1,100 , age , Proterozoic , Russia , , Keller, 1952 , - , Yuzanjian , 1.5 , 0.75 , age , Pleistocene , Japan , , Ikebe, 1977 , - ,

Zanclean The Zanclean is the lowest stage or earliest age on the geologic time scale of the Pliocene. It spans the time between 5.332 ± 0.005 Ma (million years ago) and 3.6 ± 0.005 Ma. It is preceded by the Messinian Age of the Miocene Epoch, and fol ...

, 5.332 , 3.60 , age , Pliocene , ICS , ''Zancla'', old name for

Messina Messina (, also , ) is a harbour city and the capital of the Italian Metropolitan City of Messina. It is the third largest city on the island of Sicily, and the 13th largest city in Italy, with a population of more than 219,000 inhabitants in ...

(Italy) ,

Sequenza ''Sequenza'' (Italian for "sequence") is the name borne by fourteen compositions for solo instruments or voice by Luciano Berio. The pieces, some of which call for extended techniques, are: *''Sequenza I'' (1958; rev. 1992) for flute *''Sequenza ...

, 1868 , - ,

Zechstein The Zechstein (German either from ''mine stone'' or ''tough stone'') is a unit of sedimentary rock layers of Middle to Late Permian (Guadalupian to Lopingian) age located in the European Permian Basin which stretches from the east coast of Englan ...

, ±270 , ±250 , sub-period , Permian , Europe (unofficial) , , Lehmann, 1756 , - , Zemorrian , 33.5 , 22.0 , age , Oligo-Miocene , California , , Kleinpell, 1938 , - , Zhungxian , 505 , 501 , age , Cambrian , China , , , - , Zuzhungian , 509 , 503 , age , Cambrian , China , ,

References

Literature

*; 1975: ''The type Wenlock series'', Report of the Institute of Geological Sciences, 75(13), pp. 1–19. *; 1971: ''A correlation of Silurian rocks in the British Isles'', Journal of the

Geological Society The Geological Society of London, known commonly as the Geological Society, is a learned society based in the United Kingdom. It is the oldest national geological society in the world and the largest in Europe with more than 12,000 Fellows. Fe ...

127(2), pp. 103–136. *; 2004: ''A Geologic Time Scale 2004'',

Cambridge University , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...

Press,

Cambridge Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...

, . *; 2004: ''U-Pb zircon date from the Neoproterozoic Ghaub Formation, Namibia: Constraints on Marinoan glaciation'', Geology 32(9), pp. 817–820. *; 1980: ''Ludlow stages'', Lethaia 13, p. 268, . *; 2005: ''Global time scale and regional stratigraphic reference scales of Central and West Europe, East Europe, Tethys, South China, and North America as used in the Devonian–Carboniferous–Permian Correlation Chart 2003 (DCP 2003)'', Palaeogeography, Palaeoclimatology, Palaeoecology 240, pp. 318–372. *; 1998: ''The Gelasian Stage (Upper Pliocene): a new unit of the global standard chronostratigraphic scale'', Episodes 21(2), pp. 82–87. {{DEFAULTSORT:List Of Geochronologic Names *Names Geochronologic names Geologic time scales of Earth Geochronologic names