Tectonic plate
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed durin ...
interactions are classified into three basic types:
*
Convergent boundaries are areas where plates move toward each other and collide. These are also known as compressional or destructive boundaries.
**
Obduction zones occurs when the ''continental'' plate is pushed under the ''oceanic'' plate, but this is unusual as the relative densities of the tectonic plates favours subduction of the ''oceanic'' plate. This causes the oceanic plate to buckle and usually results in a new mid-ocean ridge forming and turning the obduction into subduction.
**
Orogenic belts
An orogenic belt, orogen, or mobile belt, is a zone of Earth's crust affected by orogeny. An orogenic belt develops when a continental plate crumples and is uplifted to form one or more mountain ranges; this involves a series of geological proc ...
occur where two
continental plates collide and push upwards to form large
mountain range
A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have aris ...
s. These are also known as ''collision boundaries''.
**
Subduction zones
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second pla ...
occur where an ''oceanic'' plate meets a ''continental'' plate and is pushed underneath it. Subduction zones are marked by
oceanic trench
Oceanic trenches are prominent, long, narrow topography, topographic depression (geology), depressions of the seabed, ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers ...
es. The descending end of the oceanic plate melts and creates pressure in the
mantle, causing
volcano
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most oft ...
es to form.
***
Back-arc basin
A back-arc basin is a type of geologic Structural basin, basin, found at some convergent boundary, convergent plate boundaries. Presently all back-arc basins are submarine features associated with island arcs and subduction zones, with many found ...
s can form from extension in the overriding plate, in response to the displacement of the subducting slab at some
oceanic trench
Oceanic trenches are prominent, long, narrow topography, topographic depression (geology), depressions of the seabed, ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers ...
es. This paradoxically results in divergence which was only incorporated in the theory of plate tectonics in 1970, but still results in net destruction when summed over major plate boundaries.
*
Divergent boundaries are areas where plates move away from each other, forming either
mid-ocean ridge
A mid-ocean ridge (MOR) is a undersea mountain range, seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading ...
s or
rift valley
A rift valley is a linear shaped lowland between several highlands or mountain ranges produced by the action of a geologic rift. Rifts are formed as a result of the pulling apart of the lithosphere due to extensional tectonics. The linear ...
s. These are also known as constructive boundaries.
*
Transform boundaries occur when two plates grind past each other with only limited convergent or divergent activity.
Convergent boundaries (subduction zones)
* The oceanic
Nazca plate
The Nazca plate or Nasca plate, named after the Nazca region of southern Peru, is an oceanic list of tectonic plates, tectonic plate in the eastern Pacific Ocean basin off the west coast of South America. The ongoing subduction, along the Peru– ...
subducts
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second pla ...
beneath the continental
South American plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...
at the
Peru–Chile Trench.
* Just north of the Nazca plate, the oceanic
Cocos plate subducts under the
Caribbean plate and forms the
Middle America Trench
The Middle America Trench is a major subduction zone, an oceanic trench in the eastern Pacific Ocean off the southwestern coast of Middle America, stretching from central Mexico to Costa Rica. The trench is 1,700 miles (2,750 km) long an ...
.
* Oceanic crust of the
South American plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...
subducts under the
Caribbean plate in the
Lesser Antilles subduction zone
The Lesser Antilles subduction zone is a convergent plate boundary on the seafloor along the eastern margin of the Lesser Antilles Volcanic Arc. In this subduction zone, oceanic crust of the South American plate
The South American plate is ...
.
* The
Cascadia subduction zone
The Cascadia subduction zone is a convergent plate boundary, about off the Pacific coast of North America, that stretches from northern Vancouver Island in Canada to Northern California in the United States. It is capable of producing 9.0+ m ...
is where the oceanic
Juan de Fuca,
Gorda and
Explorer
Exploration is the process of exploring, an activity which has some Expectation (epistemic), expectation of Discovery (observation), discovery. Organised exploration is largely a human activity, but exploratory activity is common to most organis ...
Plates subduct under the continental North American plate.
* The oceanic
Pacific plate subducts under the
North American plate (composed of both continental and oceanic sections) forming the
Aleutian Trench
The Aleutian Trench (or Aleutian Trough) is an oceanic trench along a convergent plate boundary which runs along the southern coastline of Alaska and the Aleutian islands. The trench extends for from a triple junction in the west with the Ula ...
.
* The oceanic
Pacific plate subducts beneath the continental
Okhotsk microplate at the
Japan Trench
The Japan Trench is an oceanic trench part of the Pacific Ring of Fire off northeast Japan. It extends from the Kuril Islands to the northern end of the Izu Islands, and is at its deepest. It links the Kuril–Kamchatka Trench to the north and ...
.
* The oceanic
Philippine Sea plate
The Philippine Sea plate or the Philippine plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of ...
subducts beneath the
Eurasian plate at the
Ryukyu Trench.
* The oceanic
Pacific plate subducts under the oceanic
Philippine Sea plate
The Philippine Sea plate or the Philippine plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of ...
forming the
Mariana Trench
The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about east of the Mariana Islands; it is the deep sea, deepest oceanic trench on Earth. It is crescent-shaped and measures about in length and in width. The maxi ...
.
* The oceanic
Philippine Sea plate
The Philippine Sea plate or the Philippine plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of ...
is subducting under the
Philippine Mobile Belt
In the geology of the Philippines, the Philippine Mobile Belt is a complex portion of the tectonic boundary between the Eurasian plate and the Philippine Sea plate, comprising most of the country of the Philippines. It includes two subduction ...
forming the
Philippine Trench
The Philippine Trench (also called the Philippine Deep, Mindanao Trench, and the Mindanao Deep) is a Oceanic trench, submarine trench to the east of the Philippines. The trench is located in the Philippine sea of the western North Pacific Ocean ...
and the
East Luzon Trench
The Philippine Trench (also called the Philippine Deep, Mindanao Trench, and the Mindanao Deep) is a submarine trench to the east of the Philippines. The trench is located in the Philippine sea of the western North Pacific Ocean and continues ...
.
* The
Eurasian plate is subducting under the Philippine Mobile Belt at the
Manila Trench
The Manila Trench is an oceanic trench in the Pacific Ocean, located west of the islands of Luzon and Mindoro in the Philippines. The trench reaches a depth of about , in contrast with the average depth of the South China Sea of about . It i ...
.
* The
Sunda plate is subducting under the Philippine Mobile Belt at the
Negros Trench
The Negros Trench is an oceanic trench located northeast of the Sulu Trench and west of Negros Island Region in Visayas, the trench is located in the Sunda Plate in the southwestern region of the Pacific Ocean. The depth of the Negros Trench i ...
and the
Cotobato Trench.
* The oceanic
Australian plate
The Australian plate is or was a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when Indi ...
is subducted beneath the continental
Sunda plate along the
Sunda Trench.
* The oceanic
Solomon Sea plate is subducting beneath the
South Bismarck plate and the
New Hebrides plate driven by the mutual movements of the Australian and Pacific plates and local spreading centres.
* The oceanic
Pacific plate is subducting under the
Tonga plate at the
Tonga Trench
The Tonga Trench is an oceanic trench located in the southwestern Pacific Ocean. It is the deepest trench in the Southern hemisphere and the second deepest on Earth after the Mariana Trench. The fastest plate-tectonic velocity on Earth is occurri ...
driven by the mutual movements of the Australian and Pacific plates and local spreading centres.
* The oceanic
Pacific plate is subducting under the
Kermadec plate at the
Kermadec Trench
The Kermadec Trench is a linear ocean trench in the south Pacific Ocean. It stretches about from the Louisville Seamount Chain in the north (26°S) to the Hikurangi Plateau in the south (37°S), north-east of New Zealand's North Island. Togethe ...
north and east of New Zealand but the direction of subduction reverses south of the
Alpine Fault where the
Australian plate
The Australian plate is or was a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when Indi ...
starts subducting under the Pacific plate at the
Puysegur Trench.
*The
South American plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...
is subducting under the
South Sandwich plate, forming the
South Sandwich Trench.
*The oceanic
Australian plate
The Australian plate is or was a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when Indi ...
is subducting underneath the
New Hebrides plate forming the
New Hebrides Trench
The New Hebrides Trench (perhaps better termed the South New Hebrides Trench) is an oceanic trench which is over deep in the Southern Pacific Ocean. It lies to the northeast of New Caledonia and the Loyalty Islands, to the southwest of Vanuatu ...
.
Back arc basins
*These are often associated with minor plates and include:
** The
Tyrrhenian Basin
** The
Mariana Trough
** The
North Fiji Basin
The North Fiji Basin (NFB) is an oceanic basin west of Fiji in the south-west Pacific Ocean. It is an actively spreading back-arc basin delimited by the Fiji islands to the east, the inactive Vitiaz Trench to the north, the Vanuatu/ New Hebrides ...
** The
Lau Basin
The Lau Basin is a back-arc basin (also addressed as "interarc basin") at the Australian-Pacific plate boundary. It is formed by the Pacific plate subducting under the Australian plate. The Tonga-Kermadec Ridge, a frontal arc, and the Lau-Colvill ...
Orogenic belts
* The most dramatic orogenic belt on the planet is the one between the
African plate and the
Indo-Australian plate on one side (to the south) and the
Eurasian plate on the other side (to the north). This belt runs from New Zealand in the east-south-east, through
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
, along the
Himalayas
The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...
, through the Middle East up to the Mediterranean in the west-north-west. It is also called the "Tethyan" Zone, as it constitutes the zone along which the ancient Tethys Ocean was deformed and disappeared. The following mountain belts can be distinguished:
** The European
Alps
The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia.
...
** The
Carpathians
The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe and Southeast Europe. Roughly long, it is the third-longest European mountain range after the Urals at and the Scandinavian Mountains ...
** The
Pyrenees
The Pyrenees are a mountain range straddling the border of France and Spain. They extend nearly from their union with the Cantabrian Mountains to Cap de Creus on the Mediterranean coast, reaching a maximum elevation of at the peak of Aneto. ...
** The
Apennines
The Apennines or Apennine Mountains ( ; or Ἀπέννινον ὄρος; or – a singular with plural meaning; )Latin ''Apenninus'' (Greek or ) has the form of an adjective, which would be segmented ''Apenn-inus'', often used with nouns s ...
** The
Dinarides
The Dinaric Alps (), also Dinarides, are a mountain range in Southern and Southcentral Europe, separating the continental Balkan Peninsula from the Adriatic Sea. They stretch from Italy in the northwest through Slovenia, Croatia, Bosnia and Her ...
** The North African mountain belts such as the
Atlas Mountains
The Atlas Mountains are a mountain range in the Maghreb in North Africa. They separate the Sahara Desert from the Mediterranean Sea and the Atlantic Ocean; the name "Atlantic" is derived from the mountain range, which stretches around through M ...
** The
Karst Plateau
The Karst Plateau or the Karst region (, ), also locally called Karst, is a karst plateau region extending across the border of southwestern Slovenia and northeastern Italy.
It lies between the Vipava Valley, the low hills surrounding the val ...
of the Balkan Peninsula
** The
Caucasus
The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...
** The
Zagros
The Zagros Mountains are a mountain range in Iran, northern Iraq, and southeastern Turkey. The mountain range has a total length of . The Zagros range begins in northwestern Iran and roughly follows Iran's western border while covering much of s ...
** The
Himalayas
The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...
** The
Indonesian Archipelago
** The
Southern Alps of New Zealand
* The
Andes
The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...
orogenic belt is the latest of a series of
orogenies along the western margin of the
South American plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...
.
Divergent boundaries

* The
East African Rift
The East African Rift (EAR) or East African Rift System (EARS) is an active continental rift zone in East Africa. The EAR began developing around the onset of the Miocene, 22–25 million years ago. It was formerly considered to be part of a l ...
(Great Rift Valley) in eastern Africa
* The
Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a Divergent boundary, divergent or constructive Plate tectonics, plate boundary) located along the floor of the Atlantic Ocean, and part of the List of longest mountain chains on Earth, longest mountai ...
system separates the
North American plate and the
South American plate
The South American plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African plate, with which it forms the southern part of the Mid ...
in the west from the
African plate and the
Eurasian plate in the east
* The
Gakkel Ridge is a slow spreading ridge located in the
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...
* The
East Pacific Rise
The East Pacific Rise (EPR) is a mid-ocean rise (usually termed an oceanic rise and not a mid-ocean ridge due to its higher rate of spreading that results in less elevation increase and more regular terrain), at a divergent tectonic plate bound ...
, extending from the South Pacific to the
Gulf of California
The Gulf of California (), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Vermejo''), is a marginal sea of the Pacific Ocean that separates the Baja California peninsula from ...
* The
Baikal Rift Zone
The Baikal Rift Zone is a series of continental rifts centered beneath Lake Baikal in southeastern Russia. Current strain in the rifts tends to be extending with some shear movement. A series of basins form along the zone for more than , creatin ...
in eastern Russia
* The
Red Sea Rift
The Red Sea Rift is a mid-ocean ridge between two tectonic plates, the African plate and the Arabian plate. It extends from the Dead Sea Transform fault system, and ends at an intersection with the Aden Ridge and the East African Rift, forming ...
* The
Aden Ridge
The Aden Ridge is a part of an active oblique rift system located in the Gulf of Aden, between Somalia and the Arabian Peninsula to the north. The rift system marks the divergent boundary between the Somali plate, Somali and Arabian plate, Arabi ...
along the southern shore of the
Arabian Peninsula
The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world.
Geographically, the ...
* The
Carlsberg Ridge
The Carlsberg Ridge is the northern section of the Central Indian Ridge, a divergent tectonic plate boundary between the African plate and the Indo-Australian plate, traversing the western regions of the Indian Ocean.
The ridge of which the Carls ...
in the eastern
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...
* The
Woodlark Basin undergoing transition from continental rifting to sea floor spreading to the east of
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
* The
Gorda Ridge off the northwest coast of North America
* The
Explorer Ridge off the northwest coast of North America
* The
Juan de Fuca Ridge
The Juan de Fuca Ridge is a Mid-ocean ridge, mid-ocean spreading center and divergent plate boundary located off the coast of the Pacific Northwest region of North America, named after Juan de Fuca. The ridge separates the Pacific Plate to the we ...
off the northwest coast of North America
* The
Chile Rise off the southeast Pacific
Transform boundaries
* The
San Andreas Fault
The San Andreas Fault is a continental Fault (geology)#Strike-slip faults, right-lateral strike-slip transform fault that extends roughly through the U.S. state of California. It forms part of the tectonics, tectonic boundary between the Paci ...
in
California
California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...
is an active transform boundary. The Pacific plate (carrying the city of
Los Angeles
Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...
) is moving northwards with respect to the North American plate.
* The
Queen Charlotte Fault on the
Pacific Northwest
The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...
coast of North America
* The
Motagua Fault
The Motagua Fault (also, Motagua Fault Zone) is a major, active fault, active left lateral-moving transform fault which cuts across Guatemala. It forms part of the tectonic boundary between the North American plate and the Caribbean plate. It i ...
, which crosses through
Guatemala
Guatemala, officially the Republic of Guatemala, is a country in Central America. It is bordered to the north and west by Mexico, to the northeast by Belize, to the east by Honduras, and to the southeast by El Salvador. It is hydrologically b ...
, is a transform boundary between the southern edge of the
North American plate and the northern edge of the
Caribbean plate.
* New Zealand's
Alpine Fault is another active transform boundary.
* The
Dead Sea Transform
The Dead Sea Transform (DST) fault system, also sometimes referred to as the Dead Sea Rift, is a series of Fault (geology), faults that run for about 1,000 km from the Marash triple junction (a junction with the East Anatolian Fault in south ...
(DST) fault which runs through the
Jordan River
The Jordan River or River Jordan (, ''Nahr al-ʾUrdunn''; , ''Nəhar hayYardēn''), also known as ''Nahr Al-Sharieat'' (), is a endorheic river in the Levant that flows roughly north to south through the Sea of Galilee and drains to the Dead ...
Valley in the Middle East.
* The
Owen fracture zone
The Owen fracture zone (OFZ), though Misnomer, misnamed as a fracture zone, is a transform fault in the northwest Indian Ocean that separates the Arabian plate, Arabian and African plates from the Indian plate. Extending north-northeast from whe ...
along the southeastern boundary of the
Arabian plate.
* The
East Anatolian and
North Anatolian faults run across much of
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
and cause large and deadly earthquakes such as the
1999 İzmit earthquake
An earthquake of moment magnitude 7.6 struck Kocaeli Province, Turkey on 17 August 1999. According to official figures, at least 18,373 people died and 48,901 people were injured during the earthquake, and 5,840 people were missing. At least 15 ...
See also
*
References
{{Structural geology
*