Open AccessScaling of stagnant‐lid convection with Arrhenius rheology and the effects of mantle melting
Author(s) -
Korenaga Jun
Publication year - 2009
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2009.04272.x
Subject(s) - rheology , scaling , mantle convection , thermodynamics , buoyancy , mantle (geology) , arrhenius equation , convection , geology , internal heating , heat flux , mechanics , geophysics , materials science , heat transfer , physics , classical mechanics , geometry , lithosphere , mathematics , paleontology , tectonics , kinetics
SUMMARY On the basis of numerical modelling and scaling analysis, a few modifications are proposed for the scaling of stagnant‐lid convection, in order to make it more applicable to the thermal evolution of terrestrial planets. The effect of using Arrhenius rheology, as opposed to more popular linear‐exponential rheology, is first investigated, and the stability analysis of top thermal boundary layer is shown to be able to capture systematic differences caused by the different kinds of temperature‐dependent viscosity. The local stability analysis is then extended to handle the effects of mantle melting such as dehydration stiffening and compositional buoyancy. A new heat‐flow scaling law incorporating these effects suggests that mantle melting may reduce the conventional prediction of surface heat flux by up to a factor of ∼5–10, and its potential impact on our understanding of planetary evolution is briefly discussed.