Fate of Subducting Slab Constrained by Seismic Tomography

Yoshio Fukao, Satoko Ohki

After the discovery of stagnant slab in the western Pacific region (Fukao et al., 1992), image of subducting slabs are extensively studied by further detailed tomographies.  Compiling those tomographic models, we derived a unified story for the fate of subducting slab: subducting slabs tend to be deflected in the Bullen transition zone (400-1000 km depth), but can sink into the lower mantle by an instability (Fukao et al. 2001). Faralon and Thethy slabs were possibly previously stagnant, but detached and deeply sank into the lower mantle by an instablity in the Eocene epoch.

Available Resources

Detailed description of our recent tomographic model is available:  WEPP2 by Fukao et al. (2001)

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