Metastable superplumes and mantle compressibility
نویسندگان
چکیده
[1] Seismically, the African superplume is known to have a sharp lateral transition in VS and an interface between seismic anomalies with high relief. Such a structure is usually unstable in conventional thermo-chemical convection models. Using a compressible thermo-chemical convection model in which each material has a distinct equation of state, we find an expanded regime of metastable superplumes. In the preferred model, superplume material has a bulk modulus 6% higher and density 2.25% higher than ambient mantle. The inferred physical properties of the superplume are consistent with subducted oceanic crust, simultaneously satisfying seismological, geodynamical, mineralogical and geochemical constraints.Citation: Tan, E., and M. Gurnis (2005), Metastable superplumes and mantle compressibility, Geophys. Res. Lett., 32, L20307, doi:10.1029/ 2005GL024190.
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