Physics
Scientific paper
May 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995e%26psl.132..157z&link_type=abstract
Earth and Planetary Science Letters, vol. 132, Issue 1-4, pp.157-166
Physics
35
Scientific paper
We have studied the dynamical effects of a stratified viscosity profile on time-dependent mantle circulations by using a 3D Boussinesq spherical-shell convection model. This particular viscosity profile, taken from the inversion of geoid data, has the distinct feature of having a large viscosity maximum in the middle lower mantle. Surface Rayleigh numbers ranging from 5 × 10 4 to 8 × 10 6 have been considered. There are several distinct differences in both the morphologies of the plumes and the sinking currents from constant viscosity models. In a viscously-stratified lower mantle, plumes are formed invariably only after the cold downwelling has reached the bottom. The mean mantle temperature is reduced and this allows for the sinking of very cold material into the deep mantle. The number of upwelling plumes is reduced and the overall circulation is stabilized, with well-organized triple junctions of cold sheets developed. The presence of internal heating increases the number of upwelling plumes and breaks up the network of downwelling sheets. These plumes become larger in size and have a hotter interior because of the nearly stationary character.
Yuen David A.
Zhang Shuxia
No associations
LandOfFree
The influences of lower mantle viscosity stratification on 3D spherical-shell mantle convection 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 lower mantle viscosity stratification on 3D spherical-shell mantle convection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The influences of lower mantle viscosity stratification on 3D spherical-shell mantle convection will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1060284