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The narrow vertical conduit, postulated to connect the plume head to the core-mantle boundary, is viewed as providing a continuous supply of magma to a hotspot. As the overlying tectonic plate moves over this hotspot, the eruption of magma from the fixed plume onto the surface is expected to form a chain of volcanoes that parallels plate motion ...
These rhyolites can form violent eruptions. [10] [11] For example, the Yellowstone Caldera was formed by some of the most powerful volcanic explosions in geologic history. However, when the rhyolite is completely erupted, it may be followed by eruptions of basaltic magma rising through the same lithospheric fissures (cracks in the lithosphere).
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation of LIPs is variously attributed to mantle plumes or to processes associated with divergent plate ...
The archipelago formed about 60 million years ago from a magma source. The African Plate then shifted the plate the archipelago rests on over a stationary mantle plume. However, this hypothesis has been scrutinized for periods of up to several million years of a lack of volcanic activity between islands. [2] [3]
Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet, which solidifies as igneous rocks. It does so through magmatic activity or igneous activity, the production, intrusion and extrusion of magma or lava. Volcanism is the surface expression of magmatism.
Plumes are postulated to rise through the mantle and begin to partially melt on reaching shallow depths in the asthenosphere by decompression melting. This would create large volumes of magma. The plume hypothesis postulates that this melt rises to the surface and erupts to form "hot spots".
Artemis Corona is a large plume formed by the upwelling of mantle derived magma and is on a scale potentially comparable to that in the Archean mantle. [1] Models using its known characteristics showed that continued magmatism from conductive heat through the plume caused gravitational collapse.
[29] [30] [15] The plume consists of unusually hot mantle rock of the asthenosphere, the ductile layer just below the lithosphere, that creeps upwards from deeper in the Earth's interior. [31] The hot asthenosphere rifts the lithosphere above the plume, allowing magma produced by decompressional melting of the plume head to find pathways to the ...