Collision zone

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A collision zone occurs when tectonic plates meet at a convergent boundary both bearing continental lithosphere. As continental lithosphere is usually not subducted due to its relatively low density, the result is a complex area of orogeny involving folding and thrust faulting as the blocks of continental crust pile up above the subduction zone. This includes the Eastern Anatolian collision zone [1] and Banda Arc–Australian collision zone. [2]

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<span class="mw-page-title-main">Plate tectonics</span> Movement of Earths lithosphere

Plate tectonics is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since about 3.4 billion years ago. The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by geoscientists after seafloor spreading was validated in the mid-to-late 1960s.

<span class="mw-page-title-main">Orogeny</span> The formation of mountain ranges

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<span class="mw-page-title-main">Subduction</span> A geological process at convergent tectonic plate boundaries where one plate moves under the other

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<span class="mw-page-title-main">Tectonics</span> Process of evolution of the Earths crust

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The Grenville orogeny was a long-lived Mesoproterozoic mountain-building event associated with the assembly of the supercontinent Rodinia. Its record is a prominent orogenic belt which spans a significant portion of the North American continent, from Labrador to Mexico, as well as to Scotland.

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This is a list of articles related to plate tectonics and tectonic plates.

The Main Uralian Fault (MUF) runs north–south through the middle of the Ural Mountains for over 2,000 km. It separates both Europe from Asia and the three, or four, western megazones of the Urals from the three eastern megazones: namely the Pre-Uralian Foredeep, West Uralian, and the Central Uralian to the west, and the Tagil-Magnitogorskian, East Uralian, and Transuralian to the east. The Russian Plate is often included as the fourth megazone to the west. On the west side of the fault the rocks represent the sediments of the eastern continental margin zone of the European Plate (Baltica). On the east the rocks are accreted oceanic and island arc basalts, ultramafics and volcanics as well as the sediments of the western continental margin zones of the Siberian craton on the north and the Kazakhstan craton on the south.

Ultra-high-pressure metamorphism refers to metamorphic processes at pressures high enough to stabilize coesite, the high-pressure polymorph of SiO2. It is important because the processes that form and exhume ultra-high-pressure (UHP) metamorphic rocks may strongly affect plate tectonics, the composition and evolution of Earth's crust. The discovery of UHP metamorphic rocks in 1984 revolutionized our understanding of plate tectonics. Prior to 1984 there was little suspicion that continental rocks could reach such high pressures.

<span class="mw-page-title-main">Eclogitization</span> The tectonic process in which the dense, high-pressure, metamorphic rock, eclogite, is formed

Eclogitization is the tectonic process in which the high-pressure, metamorphic facies, eclogite, is formed. This leads to an increase in the density of regions of Earth's crust, which leads to changes in plate motion at convergent boundaries.

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

The Banda Arc is a dual chain of islands in eastern Indonesia that is around 2,300 km long. It is the result of the collision of a continent and an intra-oceanic island arc.

<span class="mw-page-title-main">Subduction polarity reversal</span>

Subduction polarity reversal is a geologic process in which two converging plates switch roles: The over-lying plate becomes the down-going plate, and vice versa. There are two basic units which make up a subduction zone. This consists of an overriding plate and the subduction plate. Two plates move towards each other due to tectonic forces. The overriding plate will be on the top of the subducting plate. This type of tectonic interaction is found at many plate boundaries.

References

  1. R Gök, R., et al. Lithospheric structure of the continent–continent collision zone: eastern Turkey, Geophysical Journal International, 2007, Volume 169, Issue 3, Pages 789–1378
  2. Karig, Daniel E., et al., Nature and distribution of deformation across the Banda Arc–Australian collision zone at Timor, GSA Bulletin; January 1987; v. 98; no. 1; pp. 18–32