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A mantle plume is a proposed mechanism of convection within the Earth's mantle, hypothesized to explain anomalous volcanism. [2] Because the plume head partially melts on reaching shallow depths, a plume is often invoked as the cause of volcanic hotspots, such as Hawaii or Iceland, and large igneous provinces such as the Deccan and Siberian Traps.
There is an ongoing discussion about whether the hotspot is caused by a deep mantle plume or originates at a much shallower depth. [3] Recently, seismic tomography studies have found seismic wave speed anomalies under Iceland, consistent with a hot conduit 100 km (62 mi) across that extends to the lower mantle.
That mantle plumes are much more complex than originally hypothesised and move independently of each other and plates is now used to explain such observations. [ 8 ] In 2020, Wei et al. used seismic tomography to detect the oceanic plateau, formed about 100 million years ago by the hypothesized mantle plume head of the Hawaii-Emperor seamount ...
The resulting motion forms small clusters of small plumes right above the core-mantle boundary that combine to form larger plumes and then contribute to superplumes. The Pacific and African LLSVP, in this scenario, are originally created by a discharge of heat from the core (4000 K) to the much colder mantle (2000 K); the recycled lithosphere ...
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]
Diapirs also form in the Earth's mantle when a sufficient mass of hot, less dense magma assembles. Diapirism in the mantle is thought to be associated with the development of large igneous provinces and some mantle plumes. Explosive, hot volatile rich magma or volcanic eruptions are referred to generally as diatremes. Diatremes are not usually ...
Recently, some scientists have highlighted that certain characteristics associated with mantle plumes such as precursory uplift, time-progressive volcanism, and continuity between seismic anomalies in the upper and lower mantle are lacking.
Anderson also challenged traditional scientific views on how volcanoes are formed, particularly, the theory of convective mantle plumes in the Earth, as proposed by W. Jason Morgan, Anderson argued that the so-called mantle plume hypothesis is invalid and that hotspots and oceanic islands such as Hawaii or Iceland are, instead, the normal ...