Earth and Planetary Science Letters, 239(3-4), 276-285, doi:10.1016/j.epsl.2005.09.006, 2005
Plume heat flow in a numerical model of mantle convection with moving plates
Masaki Yoshida and Masaki Ogawa
Abstract
Self-consistent numerical models are presented for a two-dimensional thermal convection
with moving plates to estimate the heat flow transported by hot upwelling plumes
in both internally and basally heated mantle. The plume heat flow depends
on the internal heating rate and convective regimes but does not exceed 30%
of basal heat flow when the plates rigidly move as observed on the Earth;
the fraction of plume heat flow to basal heat flow becomes higher when the lithosphere
behaves as a stagnant lid or as a mechanically not so strong plate.
When estimated from the dynamic topography of plume-swells above hot upwelling plumes,
the plume heat flow appears to be only a small fraction of the real plume heat flow.
As a whole, the apparent plume heat flow estimated from dynamic topography remains
only a few percent of the total heat flow on the surface boundary, the value observed
for the Earth, even when the basal heating rate exceeds 50% of the total heating rate.
Such a high fraction of basal heating rate is necessary for the amplitude of topography
above hot upwelling plumes to become comparable to the value observed for the Earth, too.
It is necessary to reexamine the earlier inference that the heat released
from the core manifests itself as plume heat flow in the Earth.