Type locality, also called type area, is the locality where a particular rock type,

stratigraphic unit A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features (facies) that characterize ...

or mineral species is first identified. If the stratigraphic unit in a locality is layered, it is called a

stratotype A stratotype or type section in geology is the physical location or outcrop of a particular reference exposure of a stratigraphic sequence or stratigraphic boundary. If the stratigraphic unit is layered, it is called a stratotype, whereas the stan ...

, whereas the standard of reference for unlayered rocks is the type locality. The term is similar to the term

type site In archaeology, a type site is the site used to define a particular archaeological culture or other typological unit, which is often named after it. For example, discoveries at La Tène and Hallstatt led scholars to divide the European Iron A ...

archaeology Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landsca ...

or the term

type specimen In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary i ...

Examples of geological type localities

Rocks and minerals

Aragonite Aragonite is a carbonate mineral, one of the three most common naturally occurring crystal forms of calcium carbonate, (the other forms being the minerals calcite and vaterite). It is formed by biological and physical processes, including pre ...

: Molina de Aragón, Guadalajara,

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

Autunite Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO2)2(PO4)2·10–12H2O, is a yellow-greenish fluorescent phosphate mineral with a hardness of 2–. Autunite crystallizes in the orthorhombic system and often occurs as tabular square ...

Autun Autun () is a subprefecture of the Saône-et-Loire department in the Bourgogne-Franche-Comté region of central-eastern France. It was founded during the Principate era of the early Roman Empire by Emperor Augustus as Augustodunum to give a Ro ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

* Benmoreite: Ben More (Mull), Scotland *

Blairmorite Blairmorite is a very rare porphyritic volcanic rock named after the community of Blairmore in southwestern Alberta, Canada.Johannsen, A. 1933. A descriptive petrography of the igneous rocks, Appendix III, p. 244. Univ. of Chicago Press. It is ch ...

: Blairmore, Alberta, Canada * Boninite:

Bonin Islands The Bonin Islands, also known as the , are an archipelago of over 30 subtropical and tropical islands, some directly south of Tokyo, Japan and northwest of Guam. The name "Bonin Islands" comes from the Japanese word ''bunin'' (an archaic read ...

, Japan * Comendite: Comende, San Pietro Island,

Sardinia Sardinia ( ; it, Sardegna, label=Italian, Corsican and Tabarchino ; sc, Sardigna , sdc, Sardhigna; french: Sardaigne; sdn, Saldigna; ca, Sardenya, label=Algherese and Catalan) is the second-largest island in the Mediterranean Sea, after ...

* Cummingtonite: Cummington, Massachusetts * Dunite: Dun Mountain,

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. * Essexite:

Essex County, Massachusetts Essex County is a county in the northeastern part of the U.S. state of Massachusetts. At the 2020 census, the total population was 809,829, making it the third-most populous county in the state, and the eightieth-most populous in the countr ...

, US *

Fayalite Fayalite (, commonly abbreviated to Fa) is the iron-rich end-member of the olivine solid-solution series. In common with all minerals in the olivine group, fayalite crystallizes in the orthorhombic system (space group ''Pbnm'') with cell parame ...

: Horta, Fayal Island,

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

* Harzburgite:

Bad Harzburg Bad Harzburg (; Eastphalian: ''Bad Harzborch'') is a spa town in central Germany, in the Goslar district of Lower Saxony. It lies on the northern edge of the Harz mountains and is a recognised saltwater spa and climatic health resort. Geogra ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

Icelandite Icelandite is a type of volcanic rock, an andesite that is enriched in iron but deficient in aluminium (< 16.5% ).Carmichael, Ian S. E., Francis J. Turner and John Verhoogen, 1974, ''Igneous Petrology,'' McGraw-Hill, p. 34

: Thingmuli (Þingmúli), Iceland * Ijolite: Iivaara, Kuusamo, Finland *

Kimberlite Kimberlite is an igneous rock and a rare variant of peridotite. It is most commonly known to be the main host matrix for diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an diamond called the Star of S ...

: Kimberley, Northern Cape,

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

* Komatiite:

Komati River The Komati River, also known as the Inkomati River or Incomati River (in Mozambique, from Portuguese Rio Incomati), is a river in South Africa, Eswatini and Mozambique. Originating in north-western Eswatini, it is joined by the Crocodile R ...

, South Africa *

Labradorite Labradorite (( Ca, Na)( Al, Si)4 O8) is a calcium-enriched feldspar mineral first identified in Labrador, Canada, which can display an iridescent effect (schiller). Labradorite is an intermediate to calcic member of the plagioclase series. It ...

: Paul's Island,

Labrador , nickname = "The Big Land" , etymology = , subdivision_type = Country , subdivision_name = Canada , subdivision_type1 = Province , subdivision_name1 ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

* Lherzolite:

Étang de Lers Étang de Lers or Lake of Lers is a natural lake in the Ariège department (France). Geology Lherzolite Lherzolite is a type of ultramafic igneous rock. It is a coarse-grained rock consisting of 40 to 90% olivine along with significant ...

(Old spelling was: Étang de Lherz.) *

Mimetite Mimetite is a lead arsenate chloride mineral (Pb5(AsO4)3Cl) which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name derives from the Greek Μιμητής ''mimetes'', meaning "imitator" a ...

: ''Treue Freundschaft Mine'',

Johanngeorgenstadt Johanngeorgenstadt () is a mining town in Saxony’s Ore Mountains, 17 km south of Aue, and 27 km northwest of Karlovy Vary. It lies in the district of Erzgebirgskreis, on the border with the Czech Republic, is a state-recognized heal ...

, Germany * Mugearite: Mugeary, Skye, Scotland *

Mullite Mullite or porcelainite is a rare silicate mineral formed during contact metamorphism of clay minerals. It can form two stoichiometric forms: 3 Al2 O32 SiO2 or 2Al2O3 SiO2. Unusually, mullite has no charge-balancing cations present. As a result, th ...

: Isle of Mull,

Scotland Scotland (, ) is a Countries of the United Kingdom, country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...

Pantellerite Pantellerite is a type of volcanic rock, specifically a peralkaline rhyolite. It has a higher iron and lower aluminium composition than comendite. It is named after Pantelleria, a volcanic island in the Strait of Sicily and the type location for ...

Pantelleria Pantelleria (; Sicilian: ''Pantiddirìa'', Maltese: ''Pantellerija'' or ''Qawsra''), the ancient Cossyra or Cossura, is an Italian island and comune in the Strait of Sicily in the Mediterranean Sea, southwest of Sicily and east of the Tunisi ...

, off

Sicily (man) it, Siciliana (woman) , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = Ethnicity , demographics1_footnotes = , demographi ...

* Portlandite:

Scawt Hill Scawt Hill is a volcanic plug in County Antrim, Northern Ireland, in the borough of Larne, 5 km from the village of Ballygally. It gets its name from the Ulster Scots "" meaning scaly, scabby or rugged. Alternatively, '' 'scawt' '' mea ...

, Ballygalley,

Larne Larne (, , the name of a Gaelic territory) is a town on the east coast of County Antrim, Northern Ireland, with a population of 18,755 at the 2011 Census. It is a major passenger and freight roll-on roll-off port. Larne is administered by Mid ...

County Antrim County Antrim (named after the town of Antrim, ) is one of six counties of Northern Ireland and one of the thirty-two counties of Ireland. Adjoined to the north-east shore of Lough Neagh, the county covers an area of and has a population o ...

Northern Ireland Northern Ireland ( ga, Tuaisceart Éireann ; sco, label= Ulster-Scots, Norlin Airlann) is a part of the United Kingdom, situated in the north-east of the island of Ireland, that is variously described as a country, province or region. Nort ...

* Rodingite: Roding River,

Sovite Sovite (or sövite) is the coarse-grained variety (or facies) of carbonatite, an Intrusive rock, intrusive, igneous rock. The finer-grained variety of carbonatite is known as alvikite. The two varieties are distinguished by minor and trace element ...

Norsjø Norsjø is a lake in the municipalities of Skien, Nome and Sauherad in Vestfold og Telemark county, Norway. It is 55 km² in area and 15 meters above sea level. Norsjø is part of the Telemark Canal. Most rivers in Telemark meet Norsjø on ...

, Norway * Strontianite:

Strontian Strontian (; gd, Sròn an t-Sìthein) is the main village in Sunart, an area in western Lochaber, Highland, Scotland, on the A861 road. Prior to 1975 it was part of Argyllshire. It lies on the north shore of Loch Sunart, close to the head of ...

, Scotland (also the element strontium derived from the mineral) *

Temagamite Temagamite is a bright white palladium mercury telluride mineral with a hardness of on the Mohs scale. Its chemical formula is Pd3 Hg Te3. It was discovered at the Temagami Mine on Temagami Island, Lake Temagami in 1973, and it represents a ...

Copperfields Mine Copperfields Mine, originally known as Temagami Mine, is an abandoned copper and silver mine on Temagami Island in Lake Temagami, Ontario, Canada. The mine opened in 1955 and comprises both underground and surface workings within a sulfide ore b ...

Temagami Temagami, formerly spelled as Timagami, is a municipality in northeastern Ontario, Canada, in the Nipissing District with Lake Temagami at its heart. The Temagami region is known as ''n'Daki Menan'', the homeland of the area's First Nations c ...

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...

, Canada *

Tonalite Tonalite is an igneous, plutonic ( intrusive) rock, of felsic composition, with phaneritic (coarse-grained) texture. Feldspar is present as plagioclase (typically oligoclase or andesine) with alkali feldspar making up less than 10% of the total ...

: Tonale Pass * Trondhjemite: Follstad,

Støren is the administrative centre of Midtre Gauldal municipality in Trøndelag county, Norway. The village is located in the Gauldalen valley at the confluence of the rivers Gaula and ''Sokna''. Støren is located on the European route E06 highwa ...

, Norway *

Uraninite Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes ...

: Joachimsthal,

Austria-Hungary Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...

(now

Jáchymov Jáchymov (); german: Sankt Joachimsthal or ''Joachimsthal'') is a spa town in Karlovy Vary District in the Karlovy Vary Region of the Czech Republic. It has about 2,300 inhabitants. The historical core of the town from the 16th century is we ...

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

) * Websterite: Webster in

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and ...

. * Widgiemoolthalite: Widgiemooltha, Western Australia, Australia * Ytterbite (a.k.a. ''gadolinite''): Ytterby, Sweden

Formations

Bearpaw Formation The Bearpaw Formation, also called the Bearpaw Shale, is a geologic formation of Late Cretaceous (Campanian) age. It outcrops in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, and was named for the Bear ...

: Bear Paw Mountains,

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columb ...

, US *

Burgess Shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fo ...

: Burgess Pass on Mount Burgess,

Alberta Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...

– BC,

Calvert Formation The Calvert Formation is a geologic formation in Maryland, Virginia, and Delaware. It preserves fossils dating back to the early to middle Miocene epoch of the Neogene period. The formation is a destination for amateur fossil hunters as well as ...

: Calvert Cliffs State Park,

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

, US *

Chapel Island Formation The Chapel Island Formation is a sedimentary formation from the Burin Peninsula, Newfoundland, Canada. It is a succession of siliciclastic deposits, over thick, that were deposited during the latest Ediacaran and earliest Cambrian. Stratigrap ...

: Newfoundland, Canada *

Chattanooga Shale The Chattanooga Shale is a geologic formation in Alabama, Arkansas, Kentucky, Missouri and Tennessee. It preserves conodont fossils dating to the Devonian Period. It occurs mostly as a subsurface geologic formation composed of layers of shale. It ...

Chattanooga, Tennessee Chattanooga ( ) is a city in and the county seat of Hamilton County, Tennessee, United States. Located along the Tennessee River bordering Georgia, it also extends into Marion County on its western end. With a population of 181,099 in 2020 ...

, US *

Chazy Formation The Chazy Reef Formation is a mid-Ordovician limestone deposit in northeastern North America. It consists of some of the oldest reef systems built by a community of organisms rather than the deposit of a limited range of similar organisms, such ...

Chazy, New York Chazy is a town in northeastern Clinton County, New York, United States. The population was 4,284 at the 2010 census. The closest city is Plattsburgh, to the south. Chazy is south of the Canada–United States border. The ZIP code is 12921 ...

, US *

Fort Payne Formation The Fort Payne Formation, or Fort Payne Chert, is a geologic formation found in the southeastern region of the United States. It is a Mississippian Period cherty limestone, that overlies the Chattanooga Shale (or locally the Maury Formation), a ...

Fort Payne, Alabama Fort Payne is a city in and county seat of DeKalb County, in northeastern Alabama, United States. At the 2020 census, the population was 14,877. European-American settlers gradually developed the settlement around the former fort. It grew rap ...

, US *

Gault Formation The Gault Formation is a geological formation of stiff blue clay deposited in a calm, fairly deep-water marine environment during the Lower Cretaceous Period (Upper and Middle Albian). It is well exposed in the coastal cliffs at Copt Point in Fol ...

: Copt Point, Folkestone, UK * Holston Formation:

Holston River The Holston River is a river that flows from Kingsport, Tennessee, to Knoxville, Tennessee. Along with its three major forks (North Fork, Middle Fork and South Fork), it comprises a major river system that drains much of northeastern Tennessee, ...

, Tennessee, US * Jacobsville Sandstone: Jacobsville, Michigan, US * Ogallala Formation: High Plains, US * St. Louis Limestone: St. Louis, Missouri, US * Ste. Genevieve Limestone: Ste. Genevieve, Missouri, US * Temple Butte Formation:

Temple Butte Temple Butte, in the Grand Canyon, Arizona, US is a prominence below the East Rim. The butte lies on the west bank of the south-flowing Colorado River. The outfall from the Little Colorado River, draining from the Painted Desert to the east a ...

, Grand Canyon, US *

Upper Greensand Formation The Upper Greensand Formation is a Cretaceous formation of Albian to Cenomanian in age, found within the Wessex Basin and parts of the Weald Basin in southern England. It overlies the Gault Clay and underlies the Chalk Group. It varies in thick ...

: Weald, Sussex,

Hampshire Hampshire (, ; abbreviated to Hants) is a ceremonial and non-metropolitan county in western South East England on the coast of the English Channel. Home to two major English cities on its south coast, Southampton and Portsmouth, Hampshire ...

Waulsortian mudmound A Waulsortian mudmound is a geographical feature formed in warm tropical waters in the Viséan geological age, now transposed to the temperate regions in Europe. It is a type of bioconstruction, rich in fossils. The rock comprises light grey, unbed ...

Waulsort Waulsort ( wa, Åssôrt) is a village of Wallonia and a district of the municipality of Hastière, located in the province of Namur, Belgium. Until the reorganisation of the Municipalities of Belgium 1977, Waulsort was a municipality in its own r ...

, Namur, Belgium

References

Stratigraphy {{geology-stub

Examples of geological type localities

Rocks and minerals

Formations

See also

References