Finite element convection models: comparison of shallow and deep mantle convection, and temperatures in the mantle

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Abstract

A Finite Element Method for solving the convection problem in a fluid with position-dependent Newtonian viscosity is developed, using bicubic and biquadratic spline functions on a rectangular grid. Introducing weak (less viscous) zones at the active margins of the lithosphere, dynamical mantle convection models are established which have a nearly uniform surface (plate) velocity and a satisfactory heat flux profile. A comparison of upper and deep mantle convection shows:
— a moderate increase of viscosity with depth cannot confine the flow to the upper mantle;
— in shallow depth convection models the temperature is too low inside the cell, but deep mantle convection models yield satisfactory temperatures for the upper mantle.
For that reason deep (or whole) mantle convection should be the favored hypothesis.


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How to Cite
Kopitzke, U. (1979). Finite element convection models: comparison of shallow and deep mantle convection, and temperatures in the mantle. Journal of Geophysics, 46(1), 97-121. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/202

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