The upper boundary layer reservoir

Kellogg et al. (1999) have developed and numerically tested a model in which 

4 TW of mantle heat must cross from the layer into the convecting mantle, neglecting any component of secular cooling (see Heat and helium section). It is not yet clear what this effect would have on the thermal stability of the layer or temperature contrast with the overlying mantle. 

Overall, if such a feature were found to be viable, it must be incorporated into a comprehensive noble gas model. This could include some of the features described above of other layered mantle models. 

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