geology Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Ea ...

, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its own distinctive geologic history, which is different from that of the surrounding areas—hence the term "exotic" terrane. The suture zone between a terrane and the crust it attaches to is usually identifiable as a fault. A sedimentary deposit that buries the contact of the terrane with adjacent rock is called an overlap formation. An igneous intrusion that has intruded and obscured the contact of a terrane with adjacent rock is called a stitching pluton. Older usage of ''terrane'' simply described a series of related rock formations or an area having a preponderance of a particular rock or rock groups.

Overview

A tectonostratigraphic terrane is not necessarily an independent microplate in origin, since it may not contain the full thickness of the

lithosphere A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the portion of the upper mantle that behaves elastically on time scales of up to thousands of years ...

. It is a piece of crust which has been transported laterally, usually as part of a larger plate, and is relatively buoyant due to thickness or low density. When the plate of which it was a part subducted under another plate, the terrane failed to subduct, detached from its transporting plate, and accreted onto the overriding plate. Therefore, the terrane transferred from one plate to the other. Typically, accreting terranes are portions of

continental crust Continental crust is the layer of igneous, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called '' sial' ...

which have rifted off another continental mass and been transported surrounded by oceanic crust, or they are old

island arc Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle alo ...

s formed at some distant

subduction zone Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, ...

. A tectonostratigraphic terrane is a fault-bounded package of rocks of at least regional extent characterized by a geologic history which differs from that of neighboring terranes. The basic characteristics of these terranes is that the present spatial relations are not compatible with the inferred geologic histories. Where terranes which lie next to each other possess strata of the same age, it must be demonstrable that the geologic evolutions are different and incompatible, and there must be an absence of intermediate

lithofacies Lithofacies may refer to: * A mappable subdivision of a designated stratigraphic unit, distinguished from adjacent subdivisions on the basis of lithology; a facies characterized by particular lithologic features * The rock record of any particular ...

which could link the strata. The concept of ''tectonostratigraphic terrane '' developed from studies in the 1970s of the complicated Pacific Cordilleran orogenic margin of North America, a complex and diverse geological potpourri that was difficult to explain until the new science of plate tectonics illuminated the ability of crustal fragments to "drift" thousands of miles from their origin and fetch up, crumpled, against an exotic shore. Such terranes were dubbed " accreted terranes" by

geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, alt ...

s. When terranes are composed of repeated accretionary events, and hence are composed of subunits with distinct history and structure, they may be called superterranes.

Tectonostratigraphic terranes

Africa * Birminian Terrane * Kahiltna Terrane * Likasi Terrane * Mozambique Belt Asia *

Aldan Terrane Aldan may refer to: ;People *Gille Aldan, the first bishop of Galloway, Scotland *Andrey Aldan-Semenov (1908–1985), Russian writer *Duke Aldan, a fictional character in ''Langrisser IV'' video game ;Places *Aldan, Russia, a town in the Sakha Rep ...

* Birekte Terrane * Bargusin Terrane * Daldyn Terrane *

Magan Terrane Magan may refer to: Places *Magan (civilization), also written Makan or Makkan, an ancient region referred to in Sumerian texts *Magan, Russia, a rural locality (a ''selo'') in the Sakha Republic, Russia *Magan Airport, an airport in the Sakha Re ...

Markha Terrane Markha may refer to: * Markha, a former village, incorporated into the city of Yakutsk, Sakha Republic, Russia * Markha, Olyokminsky District, a village in Olyokminsky District, Sakha Republic, Russia * Markha (Vilyuy), a ...

Midyan Terrane Midian (; he, מִדְיָן ''Mīḏyān'' ; ar, مَدْيَن, Madyan; grc-gre, Μαδιάμ, ''Madiam'') is a geographical place mentioned in the Hebrew Bible and Quran. William G. Dever states that biblical Midian was in the "northwest Ara ...

* Shan–Thai Terrane * Tungus Terrane * Tynda Terrane *

Uchur Terrane The Uchur (russian: Учур; sah, Учур, ''Uçur'') is a river in Khabarovsk Krai and Yakutia in Russia, a right tributary of the Aldan (Lena's basin). The length of the river is . The area of its drainage basin is . The Uchur freezes up in N ...

Taiwan *

Coastal Range Terrane The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in ...

Longitudinal Valley Terrane Longitudinal is a geometric term of location which may refer to: * Longitude ** Line of longitude, also called a meridian * Longitudinal engine, an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle ...

Eastern Central Range Terrane Eastern may refer to: Transportation *China Eastern Airlines, a current Chinese airline based in Shanghai * Eastern Air, former name of Zambia Skyways * Eastern Air Lines, a defunct American airline that operated from 1926 to 1991 * Eastern Air ...

Western Central Range Terrane Western may refer to: Places *Western, Nebraska, a village in the US *Western, New York, a town in the US *Western Creek, Tasmania, a locality in Australia *Western Junction, Tasmania, a locality in Australia *Western world, countries that id ...

Hsuehshan Range Terrane Xueshan, formerly known as and by other names, is a mountain in the Heping District of Taichung, Taiwan. It is the 2nd-highest mountain in Taiwan and in East Asia, at above sea level. It is located in the Shei-Pa National Park and is visib ...

* Western Foothills Terrane * Coastal Plain Terrane Tibet * Lhasa TerraneAitchison, J. C., Ali, J. R., and Davis, A. M. (2007) "When and where did India and Asia collide?" '' Journal of Geophysical Research'', v.112, pp.1–19 * Qiangtang Terrane *

Xigaze Terrane Shigatse, officially known as Xigazê (; Nepali: ''सिगात्से''), is a prefecture-level city of the Tibet Autonomous Region of the People's Republic of China. Its area of jurisdiction, with an area of , corresponds to the histor ...

Bainang Terrane Bainang County (; ) is a county of Xigazê in the Tibet Autonomous Region The Tibet Autonomous Region or Xizang Autonomous Region, often shortened to Tibet or Xizang, is a province-level autonomous region of the People's Republic of Chin ...

Zedong Terrane Mao Zedong pronounced ; also romanised traditionally as Mao Tse-tung. (26 December 1893 – 9 September 1976), also known as Chairman Mao, was a Chinese communist revolutionary who was the founder of the People's Republic of China (PRC), ...

* Dazhuqu Terrane Australasia * Brook Street Terrane * Buller Terrane *

Caples Terrane Caples may refer to: People * Garrett Caples (b. 1972), American poet * Harry Caples (1896 - 1933), Australian representative rugby league footballer * Yvonne Caples (b. 1972), women's boxing champion Place name * Caples, Washington, United States ...

East Tasmanian Terrane East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the f ...

* Glenburgh Terrane * Dun Mountain-Maitai Terrane * Molong—Monaro Terrane * Murihiku Terrane * Narryer Gneiss Terrane * Takaka Terrane * Torlesse Composite Terrane * Waipapa Composite Terrane *

West Tasmanian Terrane 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 Sun sets on the Earth. Etymology The word "west" is a Germanic word passed into some ...

Europe * Armorican terrane *

Avalonia Avalonia was a microcontinent in the Paleozoic era. Crustal fragments of this former microcontinent underlie south-west Great Britain, southern Ireland, and the eastern coast of North America. It is the source of many of the older rocks of We ...

Avalon Composite Terrane Avalon (; la, Insula Avallonis; cy, Ynys Afallon, Ynys Afallach; kw, Enys Avalow; literally meaning "the isle of fruit r appletrees"; also written ''Avallon'' or ''Avilion'' among various other spellings) is a mythical island featured in the ...

* Balearic Terrane *

Briançonnais Terrane Briançonnais may refer to: *the people of Briançon *, a natural region of France *Briançonnais zone The Briançonnais zone or Briançonnais terrane is a piece of continental crust found in the Penninic nappes of the Alps. According to some ...

Central Highlands Terrane The Central Highlands Terrane in Scotland, also known as the Grampian Terrane, is a sequence of early Paleozoic metamorphic rocks containing many igneous intrusions. It stretches from the Great Glen Fault, south-east down to the Highland Bounda ...

Central Southern Uplands Terrane Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

Charnwood Terrane Charnwood may refer to: County of Leicestershire, United Kingdom * Borough of Charnwood, a local government district in the county of Leicestershire, England ** Charnwood Borough Council elections * Charnwood (ward), an electoral ward and admini ...

* Hebridean Terrane * Leinster—Lakesman Terrane * Midland Valley Terrane *

North Armorican Composite Terrane North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north'' is ...

Northern Highlands Terrane Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a ra ...

* Rosslare—Monian Terranes *

Southern North Sea Terrane Southern may refer to: Businesses * China Southern Airlines, airline based in Guangzhou, China * Southern Airways, defunct US airline * Southern Air, air cargo transportation company based in Norwalk, Connecticut, US * Southern Airways Express ...

* Tregor—La Hague Terrane * Wrekin Terrane Fennoscandia * Bamble Terrane * Idefjorden Terrane * Kongsberg Terrane * Telemarkia Terrane * Western Gneiss Region North America * Avalonia Terrane *

Bancroft Terrane Bancroft may refer to: People *Bancroft (surname) Places Australia * Bancroft, Queensland, a locality in the North Burnett Region, Queensland, Australia Canada *Bancroft, Ontario United Kingdom * Bancroft, Milton Keynes United States * Bancrof ...

* Buffalo Head Terrane * Cache Creek Terrane *

Carolina Terrane Carolina may refer to: Geography * The Carolinas, the U.S. states of North and South Carolina ** North Carolina, a U.S. state ** South Carolina, a U.S. state * Province of Carolina, a British province until 1712 * Carolina, Alabama, a town in t ...

* Cassiar Terrane *

Crescent Terrane Siletzia is a massive formation of early to middle Eocene epoch marine basalts and interbedded sediments in the forearc of the Cascadia subduction zone, on the west coast of North America. It forms the basement rock under western Oregon an ...

Elzevir Terrane Elzevir may refer to: Places * Elzevir, Ontario, a township in Hastings County *Elzévir is a street that runs through the 3rd arrondissement of Paris. (See: 1, 2) * Elzevir Lake, lake in the Moira River and Lake Ontario drainage basins in Twee ...

Frontenac Terrane Frontenac may refer to: People *Louis de Buade de Frontenac, Governor of New France Places Canada Quebec *Château Frontenac, hotel in Quebec City *Frontenac, Quebec *Frontenac County, Quebec *Frontenac (Montreal Metro), Montreal Metro station *F ...

Franciscan Complex The Franciscan Complex or Franciscan Assemblage is a geologic term for a late Mesozoic terrane of heterogeneous rocks found throughout the California Coast Ranges, and particularly on the San Francisco Peninsula. It was named by geologist An ...

Ganderia Terrane Ganderia or Gander Terrane (located near the town Gander, Newfoundland) is a terrane in the northern Appalachians which broke off the supercontinent Gondwana (Ma) together with Avalonia, Megumia, and Carolinia. Extent The microcontinent Aval ...

* Hottah Terrane * Insular Superterrane *

Intermontane Plate The Intermontane Plate was an ancient oceanic tectonic plate that lay on the west coast of North America about 195 million years ago. The Intermontane Plate was surrounded by a chain of volcanic islands called the Intermontane Islands, which ha ...

and Intermontane Belt * Meguma Terrane * Occidentalia Terrane *

Pacific Rim Terrane The Kula Plate was an oceanic tectonic plate under the northern Pacific Ocean south of the Near Islands segment of the Aleutian Islands. It has been subducted under the North American Plate at the Aleutian Trench, being replaced by the Pacific Pla ...

* Pearya Terrane * Quesnellia * Salinian Block *

Slide Mountain Terrane The Slide Mountain Terrane is a late Paleozoic terrane made of a complex of oceanic rocks in northern and southern British Columbia, Canada. The rocks of the terrane include Carboniferous limestones, fine grained quartz rich clastics, conglomer ...

* Smartville Block *

Sonomia Terrane The Sonomia Terrane is a geologic crustal block known as a "terrane" whose remnants today lie in northwest Nevada. The terrane acquired its name from the Sonoma Range in that region. The Sonomia Terrane is associated with the Golconda Thrust, a s ...

Steel Mountain Terrane Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...

* Stikinia * Wrangellia Terrane *

Yakutat Block The Yakutat Block is a terrane in the process of accreting to the North American continent along the south central coast of Alaska. It has been displaced about northward since the Cenozoic along the Queen Charlotte-Fairweather fault system. Th ...

* Yukon—Tanana Terrane South America * Arequipa-Antofalla *

Chaitenia Chaitenia is a distinct fragment of Earth's crust in southern Chile. Rocks of Chaitenia represents an ancient island arc that existed next to Patagonia which became eventually accreted to it. The accretion of Chaitenia to Patagonia occurred in t ...

Chilenia Chilenia was an ancient microcontinent or terrane whose history affected many of the older rocks of central Chile and western Argentina. It was once separated by oceanic crust from the Cuyania terrane to which it accreted at ~420-390 Ma when Cuyan ...

Chiloé Block The Chiloé Block or Chiloé Terrane is a geotectonic unit making up the basement of large parts of south-central Chile between 41° and 45°S. Due to its form, it is sometimes called Chiloé Sliver. The Chiloé Block is believed to be an anci ...

*Cuchilla Dionisio Terrane * Cuyania * Fitz Roy Terrane *

Madre de Dios Terrane Madre de Dios Terrane is a distinct fragment of Earth's crust in southwestern Patagonia. Subduction made the Madre de Dios Terrane collide and accrete to Patagonia (then part of Gondwana) in the Mesozoic. This accretion is thought to have happe ...

* Mejillonía *

Nico Pérez Terrane The geology of Uruguay combines areas of Precambrian-aged shield (geology), shield geological unit, units with a region of volcanic rock erupted during the Cretaceous and copious sedimentary rock, sedimentary facies the oldest of which date from t ...

* Pampia * Paranapanema block * Piedra Alta Terrane * Tandilia Terrane

References

Citations

General bibliography

* McPhee, John (1981). ''Basin and Range''. New York: Farrar, Straus and Giroux. * McPhee, John (1983). ''In Suspect Terrain''. New York: Farrar, Straus and Giroux. * McPhee, John (1993). ''Assembling California''. New York: Farrar, Straus and Giroux.

External links

West Antarctica terrane analysis

{{Structural geology