The Sunda plate is a minor tectonic plate straddling the equator in the

Eastern Hemisphere The Eastern Hemisphere is the half of the planet Earth which is east of the prime meridian (which crosses Greenwich, London, United Kingdom) and west of the antimeridian (which crosses the Pacific Ocean and relatively little land from pole to p ...

on which the majority of

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

is located. The Sunda plate was formerly considered a part of the Eurasian plate, but the GPS measurements have confirmed its independent movement at 10 mm/yr eastward relative to Eurasia.

Extent

The Sunda plate includes the

South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by South China, in the west by the Indochinese Peninsula, in the east by the islands of Taiwan island, Taiwan and northwestern Philippines (mainly Luz ...

, the

Andaman Sea The Andaman Sea (historically also known as the Burma Sea) is a marginal sea of the northeastern Indian Ocean bounded by the coastlines of Myanmar and Thailand along the Gulf of Martaban and the west side of the Malay Peninsula, and separated f ...

, southern parts of

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

Myanmar Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...

Laos Laos, officially the Lao People's Democratic Republic (LPDR), is the only landlocked country in Southeast Asia. It is bordered by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the southeast, and Thailand to the west and ...

and

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

along with

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

, southern

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

, and the islands of

Bali Bali (English:; Balinese language, Balinese: ) is a Provinces of Indonesia, province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller o ...

Lombok Lombok, is an island in West Nusa Tenggara province, Indonesia. It forms part of the chain of the Lesser Sunda Islands, with the Lombok Strait separating it from Bali to the west and the Alas Strait between it and Sumbawa to the east. It is rou ...

West Nusa Tenggara West Nusa Tenggara ( – NTB) is a provinces of Indonesia, province of Indonesia. It comprises the western portion of the Lesser Sunda Islands, with the exception of Bali which is its own province. The area of this province is which consists of ...

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

, and part of

Sulawesi Sulawesi ( ), also known as Celebes ( ), is an island in Indonesia. One of the four Greater Sunda Islands, and the List of islands by area, world's 11th-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Min ...

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, ...

. The Sunda is bounded in the east by 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 ...

Molucca Sea Collision Zone The Molucca Sea Collision Zone is postulated by paleogeologists to explain the tectonics of the area based on the Molucca Sea in Indonesia, and adjacent involved areas. Tectonics The tectonic relationship of the Sangihe plate, Halmahera plate, ...

Molucca Sea plate Located in the western Pacific Ocean near Indonesia, the Molucca Sea plate has been classified by scientists as a fully subducted microplate that is part of the Molucca Sea Collision Zone, Molucca Sea Collision Complex. The Molucca Sea plate repre ...

Banda Sea plate The Banda Sea plate is a minor tectonic plate underlying the Banda Sea in southeast Asia. This plate also carries a portion of Sulawesi Island, the entire Seram Island, and the Banda Islands. Clockwise from the east it is bounded by the Bird's ...

and

Timor plate The Timor plate is a small tectonic plate ( microplate) in Southeast Asia carrying the island of Timor and surrounding islands. The Australian plate is subducting under the southern edge of the plate, while a small divergent boundary is located ...

; to the south and west by 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 ...

; and to the north by the Burma plate, Eurasian plate; and

Yangtze plate The Yangtze plate, also called the South China block or the South China subplate, comprises the bulk of southern China. It is separated on the east from the Okinawa plate by a rift that forms the Okinawa Trough which is a back-arc basin, on the ...

. The Indo-Australian plate dips beneath the Sunda plate along the Sunda Trench also known as Java Trench, which generates frequent earthquakes and tsunamis. The plate margin between the lower Indo-Australian plate and the upper Sunda plate, features a unique form of subduction near the island of Timor. The subduction that occurred between the upper plate and lower plate started as oceanic plate subducting under oceanic. However, it then transitioned to continental passive margin subducting under oceanic plate. This rare phenomenon continues due to the previously subducted oceanic plate continuing to drag the continental plate under the oceanic upper plate. GPS data provides insights into the consequences of speed and direction of the colliding Indo-Australian plate and the Sunda plate. This data shows that lower Indo-Australian plate is the main driver for deformation seen in the nearby Sunda-Banda Arc system. The strain that is created within this system results in shortening, with the greatest concentration in the forearc and backarc. Active shortening is occurring within the Banda Orogen. The eastern, southern, and western boundaries of the Sunda plate are tectonically complex and seismically active. Only the northern boundary is relatively quiescent.

Extent

See also

References

Further reading