Geodynamics, Seismology

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Geodynamics, Seismology Plumes

• Gillian R. Foulger University of Durham, UK

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• The classical model

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• The alternative model

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Plume
Plate
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How can we test these hypotheses?
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Model Predictions

• Plume
• Uplift
• Plume head eruption
• Plume tail to the CMB
• Time-progressive volcano chain
• High temperature

• Plate
• Extension
• Volume source fusibility

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Seismology
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Downwellings (slabs)
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Ritsema et al. (1999)
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Ritsema et al. (1999)
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Upwellings (plumes)
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The Superplumes
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The Superplumes are not hot.They are dense,
chemical anomalies.
Density
Vs
Trampert et al. (2004)
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Smaller-scale features
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The Iceland mantle plume
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oops where did it go?
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Truncation colour scales
Bijwaard Spakman (1999)
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Problems with tomography

• Insufficient resolution
• Poor data coverage
• Ambiguity in interpretation

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Resolution
Pilidou et al. (2005)
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Poor data coverage
Finite-frequency tomography

• (banana doughnut tomography)

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Finite frequency tomography
Montelli et al. (2004)
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plumes seismic stations
van der Hilst de Hoop (2005)
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Ambiguity in interpretation

• Phase
• Mineral
• State
• Composition
• Temperature

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Basin Range Province, USA
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Azores
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Huge vertical exaggerations
200 km
Silveira Stutzmann (2002)
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Azores plume tail?P-wave modelno S-wave model
Yang (2006)
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and a plate model for the Azores?
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http//www.mantleplumes.org/
Resources
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Thats all folks