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06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Time scales and heterogeneous structure in geodynamic earth models
Bunge1, Richards, Lithgow-Bertelloni
1H.-P. Bunge, Institut de Physique du Globe de Paris, Laboratoire de Sismologie, 4 place Jussieu, 75252 Paris Cedex 05, France. M. A. Richards, Department of Geology and Geophysics, University of California, Berkeley, CA 94720, USA. C. Lithgo.
Science (New York, N.Y.)
|April 16, 1998
Summary
Computer models simulating mantle convection, using plate motion history, explain deep-mantle structures. These models reveal a 150-million-year timescale for mantle thermal heterogeneity, overcoming initial condition uncertainties.
Area of Science:
- Geophysics
- Earth Sciences
- Computational Modeling
Background:
- Deep-mantle structural heterogeneity is observed via seismic tomography.
- Understanding mantle convection requires integrating plate motion history and seismic data.
Purpose of the Study:
- To model mantle convection using Cenozoic and Mesozoic plate motion history.
- To explain deep-mantle structural heterogeneity and thermal evolution.
Main Methods:
- Utilizing computer models of mantle convection.
- Constraining models with geological timescales of plate motions.
- Comparing model outputs with seismic tomography data.
Main Results:
- Models explain some deep-mantle heterogeneity, particularly subduction-related structures.
- A 150-million-year timescale for mantle thermal heterogeneity generation was revealed.
- Subduction history controls lowermost mantle structure, but models did not predict all observed upwelling features.
Conclusions:
- Plate motion history is crucial for understanding mantle structure and evolution.
- Mantle convection models provide insights into deep-earth dynamics over geological timescales.
- Discrepancies between models and tomography highlight areas for future research in mantle upwelling.
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