The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer

Details The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer

Jan 2002

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002pepi..129...43s&link_type=abstract

Physics of the Earth and Planetary Interiors, Volume 129, Issue 1-2, p. 43-65.

Physics

1

Scientific paper

The entrainment dynamics in the D/''-layer are influenced by multitudinous factors, such as thermal and compositional buoyancy, and temperature-and composition-dependent viscosity. Here, we are focusing on the effect of compositionally dependent viscosity on the mixing dynamics of the D/''-layer, arising from the less viscous but denser D/''-material. The marker method, with one million markers, is used for portraying the fine scale features of the compositional components, D/''-layer and lower-mantle. The D/''-layer has a higher density but a lower viscosity than the ambient lower-mantle, as suggested by melting point systematics. Results from a two-dimensional finite-difference numerical model including the extended Boussinesq approximation with dissipation number /Di=0.3, show that a D/''-layer, less viscous than the ambient mantle by 1.5 orders of magnitude, cannot efficiently mix with the lower-mantle, even though the buoyancy parameter is as low as Rρ=0.6. However, very small-scale schlieren structures of D/''-layer material are entrained into the lower-mantle. These small-scale lower-mantle heterogeneities have been imaged with one-dimensional wavelets in order to delineate quantitatively the multiscale features. They may offer an explanation for small-scale seismic heterogeneity inferred by seismic scattering in the lower-mantle.

Affiliated with

Also associated with

No associations

Rating

The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer 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 The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The influences of composition-sand temperature-dependent rheology in thermal-chemical convection on entrainment of the D/''-layer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1838908