Anelastic convection in the mantle with variable properties

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2

Scientific paper

The convective motion and the thermal state of the Earth's mantle are investigated through the mean-field approximation, deriving the steady-state solutions of the set of conservation equations in cartesian geometry for a compressible fluid with variable viscosity, bulk modulus, thermal expansion and thermal conductivity. The density and bulk modulus are taken from the Preliminary Reference Earth Model (PREM) and the Grüneisen parameter is evaluated through the Debye-Brillouin formulation, which has been proven to be an effective approximation. Thermal expansion is derived from the thermodynamical definition of the Grüneisen parameter, and thermal conductivity and the other thermodynamic parameters are written in terms of the elastic constants according to the quasi-harmonic theory. Comparison of the solutions obtained with an exponential density profile following the Adams-Williamson equation of state and the polynomial profile of the PREM shows that the detail of the radial behaviour of density has a minor influence. The radial variation of thermal expansivity is found to produce a lower thermal gradient at high Rayleigh numbers through a complex feedback mechanism involving buoyancy and adiabatic heating. The radial dependence of thermal conductivity strongly affects both the mechanical and thermal state of the convective cells and inhibits the formation of thermal boundary layers at the bottom of the cells. In this case, the temperature dependence of the viscosity determines a `cold' and a `hot' branch, which may be related to the composition of the outer core.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Anelastic convection in the mantle with variable properties does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Anelastic convection in the mantle with variable properties, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anelastic convection in the mantle with variable properties will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1306912

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.