Relation between seismological observations, and mantle plumes and LIPs
Work with Trond Torsvik, Kevin Burke and Mark Smethurst indicates that plumes and Large Igneous Provinces (LIPs) are mainly generated at the edges of presumed chemically distinct Large Low Shear Velocity Provinces (LLSVPs) in the lowermost mantle. The figure below (from Torsvik et al., 2006) shows that both reconstructed LIP eruption sites (shown as circles) and hotspots (shown as crosses) tend to fall close to the 1 % slow contour (black line) of the smean tomography model, which is also where steep horizontal gradients (colored blobs) tend to occur.
Correlations between geodynamic models of tilted plume conduits and tomography models were studied with Lapo Boschi and Thorsten Becker. We found that modelled tilted plume conduits for a compilation of 44 hotspots correlate better with tomography than both tilted conduits starting at random locations, and vertical conduits beneath hotspots.
More detailed comparisions of computed tilted plume conduits with tomographic images are carried out as part of projects led by Jianshe Lei for a proposed Hainan Plume and Robert Smith for the Yellowstone plume, and with Wim Spakman for a proposed Kazakhstan plume.

• Torsvik, T. H., M. A. Smethurst, K. Burke and B. Steinberger (2006). Large igneous provinces generated from the margins of the large low-velocity provinces in the deep mantle, Geophys. J. Int., 167, 1447-1460. doi:10.1111/j.1365-246X.2006.03158.x [pdf]
• Boschi, L., T. W. Becker and B. Steinberger (2007). Mantle plumes: dynamic models and seismic images, Geochem. Geophys. Geosyst., doi:10.1029/2007GC001733 [pdf]
• Burke, K., B. Steinberger, T. H. Torsvik and M. A. Smethurst (2008). Plume Generation Zones at the margins of Large Low Shear Velocity Provinces on the the Core-Mantle Boundary, Earth Planet. Sci. Lett., 265, 49-60, doi:10.1016/j.epsl.2007.09.042 [pdf].
• Torsvik, T. H., M. A. Smethurst, K. Burke and B. Steinberger (2008). Long term stability in deep mantle structure: Evidence from the ~300 Ma Skagerrak-Centered Large Igneous Province (the SCLIP), Earth Planet. Sci. Lett., doi:10.1016/j.epsl.2007.12.004.
• Boschi, L., T. W. Becker and B. Steinberger (in revision). On the statistical significance of correlations between synthetic mantle plumes and tomographic models, Phys. Earth Planet. Inter., [pdf]

Power Point Presentation: What are the low-velocity anomalies in the deep mantle?

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