Search results
Results from the WOW.Com Content Network
Thermal or compositional fluid-dynamical plumes produced in that way were presented as models for the much larger postulated mantle plumes. Based on these experiments, mantle plumes are now postulated to comprise two parts: a long thin conduit connecting the top of the plume to its base, and a bulbous head that expands in size as the plume rises.
The production of magma is accomplished in multiple ways: 1) subduction of oceanic crust, 2) creation of a hot spot from a mantle plume, and 3) divergence of oceanic or continental plates. The subduction of oceanic crust produces a magmatic melt usually at great depth. Yellowstone National Park is a hot spot located within the center of a ...
Mantle convection is the very slow creep of Earth's solid silicate mantle as convection currents carry heat from the interior to the planet's surface. [2] [3] Mantle convection causes tectonic plates to move around the Earth's surface. [4] The Earth's lithosphere rides atop the asthenosphere, and the two form the components of the upper mantle ...
The temperature of the mantle increases rapidly in the thermal boundary layers at the top and bottom of the mantle, and increases gradually through the interior of the mantle. [22] Although the higher temperatures far exceed the melting points of the mantle rocks at the surface (about 1,500 K (1,200 °C; 2,200 °F) for representative peridotite ...
Mantle plumes were first proposed by J. Tuzo Wilson in 1963 [4] [non-primary source needed] and further developed by W. Jason Morgan in 1971. A mantle plume is posited to exist where hot rock nucleates [clarification needed] at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust. [5]
The formation and development of plumes in the early mantle contributed to triggering the lateral movement of crust across the Earth's surface. [18] The effect of upwelling mantle plumes on the lithosphere can be seen today through local depressions around hotspots such as Hawaii. The scale of this impact is much less than that exhibited in the ...
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 ...
A mantle plume rises from the core to the surface. P-T-t paths play an important role in the development of plume tectonics, supported by anticlockwise P-T paths. [11] [49] Plume tectonics are considered to be the dominant process forming the Archean crust with evidence from the study of the Archean cratonic blocks in the North China Craton.