Thermal evolution of Earth: Models with time-dependent layering of mantle convection which satisfy the Urey ratio constraint

Physics – Geophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

6

Tectonophysics: Heat Generation And Transport, Tectonophysics: Planetary Interiors (5430, 5724), Mathematical Geophysics: Modeling, Tectonophysics: Rheology-Mantle

Scientific paper

We present a new set of Earth thermal history calculations in which the effect of increasing mantle layering with convection Rayleigh number is included in a parameterized mantle convection model. We demonstrate that the inclusion of this effect results in strong buffering of the upper mantle temperature and surface heat flow. Models of this type deliver the observed surface heat flow when geochemically constrained internal heating rates (Urey ratios) are assumed with reasonable initial core temperatures. The surface heat flow is also relatively unchanged for the last 3 Gyr of Earth history in models of this kind, in accord with geological inferences concerning ancient geotherms derived from the study of Archean continental materials. In contrast, models with constant degrees of layering spanning the range from whole mantle to fully layered convection are shown to require unreasonably high initial core temperatures in order to meet the surface heat flow constraint. All successful models require that the coupling of heat flow between reservoirs be smaller than would be expected if mantle viscosities are those inferred on the basis of postglacial rebound (PGR) observations. This may indicate that viscosity for convection is significantly greater than that for rebound and hence that mantle rheology is non-Newtonian and that the PGR process is governed by transient rather than steady state creep.

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

Thermal evolution of Earth: Models with time-dependent layering of mantle convection which satisfy the Urey ratio constraint 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 Thermal evolution of Earth: Models with time-dependent layering of mantle convection which satisfy the Urey ratio constraint, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermal evolution of Earth: Models with time-dependent layering of mantle convection which satisfy the Urey ratio constraint will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1213439

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