scholarly journals Reflection and transmission of seismic waves under initial stress at the earth's core-mantle boundary

1980 ◽  
Vol 3 (3) ◽  
pp. 591-598
Author(s):  
Sukhendu Dey ◽  
Sushil Kumar Addy
Keyword(s):  
Initial Stress ◽  
Seismic Waves ◽  
Reflection And Transmission Coefficients ◽  
Earth’S Core ◽  
Reflection And Transmission ◽  
Earth's Core ◽  
Mantle Boundary ◽  
Core Mantle Boundary ◽  
Transmission Coefficients ◽  
The Core

In the present paper the influence of the initial stress is shown on the reflection and transmission ofPwaves at the core-mantle boundary. Taking a particular value of the inherent initial stress, the variations of reflection and transmission coefficients with respect to the angle of emergence are represented by graphs. These graphs when compared with those having no initial stress show that the effect of the initial stress is to produce a reflectedPandSwaves with numerically higher amplitudes but a transmittedPwave with smaller amplitude. A method is also indicated in this paper to calculate the actual value of the initial stress near the core-mantle boundary by measuring the amplitudes of incident and reflectedPwaves.

Melting of iron–silicon alloy up to the core–mantle boundary pressure: implications to the thermal structure of the Earth’s core

2009 ◽  
Vol 37 (6) ◽  
pp. 353-359 ◽  
Author(s):  
Hidetoshi Asanuma ◽  
Eiji Ohtani ◽  
Takeshi Sakai ◽  
Hidenori Terasaki ◽  
Seiji Kamada ◽  
...  
Keyword(s):  
Thermal Structure ◽  
Earth’S Core ◽  
Earth's Core ◽  
Silicon Alloy ◽  
Mantle Boundary ◽  
Core Mantle Boundary ◽  
Iron Silicon ◽  
The Core

scholarly journals Thermal conductivity of Fe-Si alloys and thermal stratification in Earth’s core

2021 ◽  
Vol 119 (1) ◽  
pp. e2119001119
Author(s):  
Youjun Zhang ◽  
Kai Luo ◽  
Mingqiang Hou ◽  
Peter Driscoll ◽  
Nilesh P. Salke ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
High Pressure ◽  
Transport Properties ◽  
Outer Core ◽  
Earth’S Core ◽  
High Pressure And Temperature ◽  
Earth's Core ◽  
Mantle Boundary ◽  
Core Mantle Boundary ◽  
The Core

Light elements in Earth’s core play a key role in driving convection and influencing geodynamics, both of which are crucial to the geodynamo. However, the thermal transport properties of iron alloys at high-pressure and -temperature conditions remain uncertain. Here we investigate the transport properties of solid hexagonal close-packed and liquid Fe-Si alloys with 4.3 and 9.0 wt % Si at high pressure and temperature using laser-heated diamond anvil cell experiments and first-principles molecular dynamics and dynamical mean field theory calculations. In contrast to the case of Fe, Si impurity scattering gradually dominates the total scattering in Fe-Si alloys with increasing Si concentration, leading to temperature independence of the resistivity and less electron–electron contribution to the conductivity in Fe-9Si. Our results show a thermal conductivity of ∼100 to 110 W⋅m−1⋅K−1 for liquid Fe-9Si near the topmost outer core. If Earth’s core consists of a large amount of silicon (e.g., > 4.3 wt %) with such a high thermal conductivity, a subadiabatic heat flow across the core–mantle boundary is likely, leaving a 400- to 500-km-deep thermally stratified layer below the core–mantle boundary, and challenges proposed thermal convection in Fe-Si liquid outer core.

scholarly journals Reflection and transmission from a plane layered core-mantle boundary

1967 ◽  
Vol 57 (3) ◽  
pp. 477-499
Author(s):  
Ta-Liang Teng
Keyword(s):  
Seismic Waves ◽  
Transfer Functions ◽  
Reflection And Transmission ◽  
S Waves ◽  
Mantle Boundary ◽  
Core Mantle Boundary ◽  
Complex Arithmetic ◽  
The Core ◽  
General Guide ◽  
Transmission And Reflection

abstract A class of transfer functions in terms of layer matrices is derived, giving the transmission and reflection of plane harmonic P or S waves incident from either side of a plane layered core-mantle boundary. A computer program coded in complex arithmetic for the IBM 7094 is used to evaluate these functions. Numerical values obtained from five suggested models of the core-mantle boundary are compared and discussed. The aim is to formulate the method, and to establish some general guide, for the studies of the structure of the core-mantle boundary and the affenuation of seismic waves inside the core.

Hydromagnetic spin-up under conditions of the earth's core-mantle boundary

1978 ◽  
Vol 22 (3) ◽  
pp. 276-282
Author(s):  
Jozef Brestenský ◽  
Gustáv Siráň ◽  
I. Cupal
Keyword(s):  
Earth’S Core ◽  
Earth's Core ◽  
Mantle Boundary ◽  
Core Mantle Boundary
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