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The deep mantle plume hypothesis on Canary hotspot formation proposes how the current-day Canary islands rested above a province of tholeiitic magma during the Triassic Period. The province, known as the Central Atlantic Magmatic Province (CAMP), became active and extended over 10 million km 2 , developing into what scientists call today the ...
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.
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).
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.
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 ...
Magma (from Ancient Greek μάγμα (mágma) 'thick unguent') [1] is the molten or semi-molten natural material from which all igneous rocks are formed. [2] Magma (sometimes colloquially but incorrectly referred to as lava) is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial ...
The Samoa hotspot is marked 35 on map. Diagram showing how islands are formed by hotspots. The Samoa hotspot is a volcanic hotspot located in the south Pacific Ocean.The hotspot model describes a hot upwelling plume of magma through the Earth's crust as an explanation of how volcanic islands are formed.