Plume fluxes from seismic tomography

G. Nolet (1) , S.I. Karato (2) , R. Montelli (1)

1 Department of Geosciences [Princeton]
2 Department of Geology and Geophysics

We use mantle previous termplumenext term images from finite frequency previous termtomographynext term and the Stokes equation to obtain a quantitative estimate of the heat and volume previous termfluxnext term across several well resolved previous termplumenext term sections in mid-mantle. Although not a perfect barrier, widening of previous termplumesnext term just below 670 km depth indicates that the phase transition from ringwoodite to perovskite plus magnesowüstite and possibly iron enrichment of the lower mantle resists previous termplumenext term passage into the upper mantle. Estimated heat- and volume previous termfluxnext term for individual previous termplumesnext term at mid-mantle depths is greater than predicted by surface observations of buoyancy previous termflux,next term even for very high viscosity. Although uncertainties are large, the high previous termfluxnext term observed in previous termplumesnext term at mid-mantle depth is compatible with the view that previous termplumesnext term are responsible for all upward advective heat transport in the lower mantle that eventually breaks through into the upper mantle.

G. Nolet, S.I. Karato, R. Montelli. Plume fluxes from seismic tomography. Earth and Planetary Science Letters, 2006, 248 (3-4), pp.685-699. ⟨10.1016/j.epsl.2006.06.011⟩. ⟨hal-00407617⟩