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These plates are often grouped with an adjacent principal plate on a tectonic plate world map. For purposes of this list, a microplate is any plate with an area less than 1 million km 2 . Some models identify more minor plates within current orogens (events that lead to a large structural deformation of Earth's lithosphere ) like the Apulian ...
Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago.
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. [citation needed]
Some volcanoes occur in the interiors of plates, and these have been variously attributed to internal plate deformation [15] and to mantle plumes. Tectonic plates may include continental crust or oceanic crust, or both. For example, the African plate includes the continent and parts of the floor of the Atlantic and Indian Oceans.
In the first case, the process has a local extent, usually within the volcanic area. Typical examples include the development of calderas and resurgences, pit craters, dikes, sills, laccoliths, magma chambers, eruptive fissures, volcanic rift zones and any type of volcano flank dynamics, including sector collapses. In the second case, the ...
Because tectonic plates move across mantle plumes, each volcano becomes inactive as it drifts off the plume, and new volcanoes are created where the plate advances over the plume. The Hawaiian Islands are thought to have been formed in such a manner, as has the Snake River Plain , with the Yellowstone Caldera being part of the North American ...
The northwards collision of the Australian plate with the Sunda plate (Sundaland plate, previously classified as part of Eurasian plate) has a maximum convergence velocity of 7.3 cm (2.9 in) per year ± 0.8 cm (0.31 in) per year at the Java Trench decreasing to 6.0 cm (2.4 in) ± 0.04 cm (0.016 in) per year at the southern Sumatra Trench.
A hotspot volcano is center. [8] Movements of tectonic plates create volcanoes along the plate boundaries, which erupt and form mountains. A volcanic arc system is a series of volcanoes that form near a subduction zone where the crust of a sinking oceanic plate melts and drags water down with the subducting crust. [9]