asthenosphere


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as·then·o·sphere

 (ăs-thĕn′ə-sfîr′)
n.
A zone of the earth's mantle that lies beneath the lithosphere and consists of several hundred kilometers of deformable rock.

[Greek asthenēs, weak; see asthenia + sphere.]

asthenosphere

(əsˈθiːnəˌsfɪə; -ˈθɛn-)
n
(Geological Science) a thin semifluid layer of the earth (100–200 km thick), below the outer rigid lithosphere, forming part of the mantle and thought to be able to flow vertically and horizontally, enabling sections of lithosphere to subside, rise, and undergo lateral movement. See also isostasy
[C20: from astheno-, from Greek asthenēs weak + sphere]

as•then•o•sphere

(æsˈθɛn əˌsfɪər)

n.
the region below the lithosphere where rock is less rigid than that above and below it.
[1910–15; < Greek asthen(ḗs) frail (see asthenia) + -o- + -sphere]

as·then·o·sphere

(ăs-thĕn′ə-sfîr′)
The upper part of the Earth's mantle. The asthenosphere lies beneath the lithosphere and consists of several hundred miles of partially molten rock. Because it is partially molten, seismic waves passing through this layer have slow velocities. Compare atmosphere, hydrosphere, lithosphere.

asthenosphere

A dense, plastic layer of mantle below the lithosphere.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.asthenosphere - the lower layer of the crustasthenosphere - the lower layer of the crust  
layer - a relatively thin sheetlike expanse or region lying over or under another
crust, Earth's crust - the outer layer of the Earth
Translations
asthénosphère
astenosfera
References in periodicals archive ?
This convection is presented as whole mantle or whole asthenosphere cells with hot material rising under the Earth's divergent plate boundaries and cooler material sinking at the convergent boundaries with the lithosphere dragged along by the horizontal flow of the asthenosphere (Figure 1).
This important geodynamic change induced upwelling of asthenosphere material, which led to adakitic magmatic activity and east-west extension.
These plates are not static, but move relative to each other at varying speeds, "gliding" over a viscous asthenosphere. Exactly what mechanism or mechanisms are behind their movement is still debated, but are likely to include convection currents within the asthenosphere and the forces generated at the boundaries between plates.
The archipelago is characterised by numerous contemporaneous volcanoes, some with plume magma sources, others from the asthenosphere, possibly due to the young and thin oceanic crust.
This stage is accompanied by upwelling of the hotter asthenosphere which worms up the lithosphere.
Therefore, quartz diorite might be formed in the post-collision extension environment after the collision of Lhasa block and Qiangtang block; lower crust delamination caused uplifting of asthenosphere material, which further caused partial melting of lithospheric mantle and let basic melt mix with the acid melt.
It floats on a layer called the asthenosphere - a silly putty like plastic material directly below it a few 100 miles in thickness.
Prograde metamorphism of the bounding thick crust may have led to formation of a dense, eclogitic lower crustal root that had detached from the more buoyant overlying granulitic crust and sank, together with its attached underlying lithospheric mantle, into the convecting asthenosphere of the backarc region (see Krystopowicz and Currie 2013).
Although the lithosphere and asthenosphere have to be distinguished by the viscosity, imaging the Earth's structure in terms of viscosity provides only weak resolution even with the most recent technology, (25) compared with seismic or electromagnetic imaging methods.
The dense crust would have dripped down into the mantle, triggering a return flow of mantle material from the asthenosphere that would have melted to form new primary crust.
Francalanci, "Generation of oceanic-island basalt-type volcanism in the western Trans-Mexican volcanic belt by slab rollback, asthenosphere infiltration, and variable flux melting," Geology, vol.