Sunda Plate

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Sunda Plate
SundaPlate.png
Type Minor
Movement1east
Speed111–14 mm/year
Features Mainland Southeast Asia, Borneo, Java, Sumatra, Bali, South China Sea
1Relative to the African Plate

The Sunda Plate is a minor tectonic plate straddling the Equator in the Eastern Hemisphere on which the majority of Southeast Asia is located. [1]

Contents

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. [2]

Extent

The Sunda Plate includes the South China Sea, the Andaman Sea, southern parts of Vietnam, Myanmar, Laos and Thailand along with Malaysia, Singapore, Cambodia, southern Philippines, and the islands of Bali, Lombok, West Nusa Tenggara, Borneo, Sumatra, Java, and part of Sulawesi in Indonesia.

The Sunda is bounded in the east by the Philippine Mobile Belt, Molucca Sea Collision Zone, Molucca Sea Plate, Banda Sea Plate and Timor Plate; to the south and west by the Australian Plate; and to the north by the Burma Plate, Eurasian Plate; and Yangtze Plate. The Indo-Australian Plate dips beneath the Sunda Plate along the Sunda Trench also known as Java Trench, which generates frequent earthquakes and tsunamis. [1]

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 the 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. [3] [4]

The eastern, southern, and western boundaries of the Sunda Plate are tectonically complex and seismically active. Only the northern boundary is relatively quiescent.

See also

Related Research Articles

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<span class="mw-page-title-main">Australian Plate</span> Major tectonic plate separated from Indo-Australian Plate about 3 million years ago

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<span class="mw-page-title-main">Sunda Arc</span> Volcanic island arc in Indonesia

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<span class="mw-page-title-main">Burma Plate</span> Minor tectonic plate in Southeast Asia

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The Sunda Trench, earlier known as and sometimes still indicated as the Java Trench, is an oceanic trench located in the Indian Ocean near Sumatra, formed where the Australian-Capricorn plates subduct under a part of the Eurasian Plate. It is 3,200 kilometres (2,000 mi) long with a maximum depth of 7,290 metres. Its maximum depth is the deepest point in the Indian Ocean. The trench stretches from the Lesser Sunda Islands past Java, around the southern coast of Sumatra to the Andaman Islands, and forms the boundary between the Indo-Australian Plate and Eurasian Plate. The trench is considered to be part of the alpida Belt as well as one of oceanic trenches around the northern edges of the Australian Plate.

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<span class="mw-page-title-main">Banda Sea Plate</span> Minor tectonic plate underlying the Banda Sea in southeast Asia

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<span class="mw-page-title-main">Molucca Sea Plate</span> Small fully subducted tectonic plate near Indonesia

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<span class="mw-page-title-main">Philippine Mobile Belt</span> Tectonic boundary

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<span class="mw-page-title-main">Sunda megathrust</span> Geological feature

The Sunda megathrust is a fault that extends approximately 5,500 km (3300 mi) from Myanmar (Burma) in the north, running along the southwestern side of Sumatra, to the south of Java and Bali before terminating near Australia. It is a megathrust, located at a convergent plate boundary where it forms the interface between the overriding Eurasian plate and the subducting Indo-Australian plate. It is one of the most seismogenic structures on Earth, being responsible for many great and giant earthquakes, including the 2004 Indian Ocean earthquake and tsunami that killed over 227,000 people. The Sunda megathrust can be divided into the Andaman Megathrust, Sumatra(n) Megathrust and Java(n) Megathrust. The Bali-Sumbawa segment is much less active and therefore does not have the "megathrust" term associated with it.

<span class="mw-page-title-main">Kilinailau Trench</span> Ocean trench in south western Pacific Ocean

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<span class="mw-page-title-main">Banda Arc</span> Set of island arcs in eastern Indonesia

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<span class="mw-page-title-main">Divergent double subduction</span> Special type of Tectonic process

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<span class="mw-page-title-main">Subduction tectonics of the Philippines</span>

The subduction tectonics of the Philippines is the control of geology over the Philippine archipelago. The Philippine region is seismically active and has been progressively constructed by plates converging towards each other in multiple directions. The region is also known as the Philippine Mobile Belt due to its complex tectonic setting.

References

  1. 1 2 Whitten, T; Soeriaatmadja, R. E.; Suraya A. A. (1996). The Ecology of Java and Bali. Hong Kong: Periplus Editions Ltd. p. 87. ISBN   978-9625938882.
  2. Socquet, Anne; Wim Simons; Christophe Vigny; Robert McCaffrey; Cecep Subarya; Dina Sarsito; Boudewijn Ambrosius; Wim Spakman (2006). "Microblock rotations and fault coupling in SE Asia triple junction (Sulawesi, Indonesia) from GPS and earthquake slip vector data". Journal of Geophysical Research. 111 (B8). Bibcode:2006JGRB..111.8409S. doi: 10.1029/2005JB003963 . ISSN   0148-0227.
  3. Nugroho, Hendro; Harris, Ron; Lestariya, Amin W.; Maruf, Bilal (December 2009). "Plate boundary reorganization in the active Banda Arc–continent collision: Insights from new GPS measurements". Tectonophysics. 479 (1–2): 52–65. doi:10.1016/j.tecto.2009.01.026. ISSN   0040-1951.
  4. Harris, Ron (2009-06-01). "Transition from subduction to arc-continent collision: Geologic and neotectonic evolution of Savu Island, Indonesia". Geosphere. 5 (3). doi: 10.1130/ges00209.s1 . ISSN   1553-040X.

Further reading