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Gross Earth Data and Mantle Convection: New Inferences of Mantle Viscosity

  • Alessandro M. Forte
  • W. Richard Peltier
Chapter
Part of the NATO ASI Series book series (ASIC, volume 334)

Abstract

We introduce a theory for calculation of the buoyancy-induced flow expected on the basis of seismic tomographic inferences of lateral heterogeneity in the mantle, for a compressible mantle possessing an arbitrary radial viscosity stratification. This theory includes the first fully consistent treatment of all gravitationally-induced loads arising from the effects of self-gravitation. We employ this theory to calculate the nonhydrostatic geoid and surface horizontal divergence and, by matching these predicted surface observables to the corresponding observational data, we constrain the depth variation of mantle viscosity. We also introduce a new formalism for calculating the flow that is consistent with the existence of rigid tectonic plates at the Earth’s surface. This predicted plate-like surface flow is sensitive to the absolute value of the mantle viscosity and, by matching it to the observed plate velocities, we infer mantle viscosities that are compatible with those inferred from glacial isostatic adjustment data.

Keywords

Plate Motion Mantle Convection Horizontal Divergence Mantle Flow Density Heterogeneity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 1991

Authors and Affiliations

  • Alessandro M. Forte
    • 1
  • W. Richard Peltier
    • 2
  1. 1.Department of Earth and Planetary SciencesHarvard UniversityCambridgeUSA
  2. 2.Department of PhysicsUniversity of TorontoTorontoCanada

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