Results 131 to 140 of about 1,186 (179)

Is the asthenosphere electrically anisotropic?

Earth and Planetary Science Letters, 2000
Abstract Two techniques for resolving the conductance of an electrically conductive asthenosphere are presented. The first technique combines observatory electromagnetic data in the period range of the daily variation and longer, which provides penetration depths of 400 km and deeper, with laboratory data of the conductivity of upper mantle materials.
Karsten Bahr, Al Duba
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Electromagnetic Studies of the Lithosphere and Asthenosphere

Surveys in Geophysics, 1999
In geodynamic models of the Earth's interior, the lithosphere and asthenosphere are defined in terms of their rheology. Lithosphere has high viscosity, and can be divided into an elastic region at temperatures below 350 °C and an anelastic region above 650 °C.
Graham Heinson
exaly   +2 more sources

Melt squirt in the asthenosphere

Journal of Geophysical Research, 1975
The interpretation of the seismic low-velocity zone as a region of partially molten rock is extended to explain the transient displacements following the 1946 Nankaido earthquake. Three partial melt models are considered to account for the observed time constant of 3–5 years: large-scale diffusion of melt through a porous matrix can decay over ...
Gerald Mavko, Amos Nur
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A Global View of the Lithosphere-Asthenosphere Boundary

Science, 2009
Seismic imaging reveals a global velocity anomaly at depths of 70 to 100 kilometers that may be from some melt or a strong fabric in Earth’s mantle.
Rychert, C.A., Shearer, P.M.
openaire   +3 more sources

Dissipative heating in shear plow of the asthenosphere

Fluid Dynamics, 1985
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Maron, V. I., Nikolaevskij, V. N.
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On the ionospheric effects of asthenospheric earthquakes

Physics of the Earth and Planetary Interiors, 1989
Abstract Characteristic foF2 variations during preparation of the asthenospheric Hindukush earthquake of 12 September 1983 are investigated. Stable effects in F2 layer critical frequency variations are revealed which can be considered as earthquake precursors.
M.N. Fatkullin, T.I. Zelenova, A.D. Legenka   +2 more
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A CO2 Charged Asthenosphere

Nature Physical Science, 1972
Solubility considerations lead to a model of the asthenosphere which contains a CO2-rich liquid phase. The model explains variations in the asthenosphere between ocean and shield areas.
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Stress and viscosity in the asthenosphere

Tectonophysics, 1979
Abstract Stresses and effective viscosities in the asthenosphere to a depth of 400 km are calculated on the basis of Weertmans “temperature method” i.e., on relating viscosity to the ratio of the temperature to the melting point (=homologous temperature).
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Asthenosphere readjustment and the earthquake cycle

Journal of Geophysical Research: Solid Earth, 1978
A simple two‐dimensional model of the earthquake cycle (preearthquake strain accumulation, coseismic strain release, and postseismic readjustment) has been constructed from the Nur‐Mavko solution for a screw dislocation in an elastic plate (lithosphere) overlying a viscoelastic substrate (asthenosphere).
J. C. Savage, W. H. Prescott
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Enriched Asthenosphere and Depleted Plumes

International Geology Review, 1996
“Lithosphere” and “asthenosphere” are mechanical concepts; “depleted mantle” (DM), “enriched mantle” (EM), and “primitive mantle” (PM) are chemical concepts. Upper mantle, lower mantle, and D″ are seismological subdivisions. Geochemistry provides few constraints on the locations of mantle reservoirs, but it is generally assumed that the MORB reservoir (
openaire   +2 more sources