Metastable superplumes and mantle compressibility
Article first published online: 22 OCT 2005
Copyright 2005 by the American Geophysical Union.
Geophysical Research Letters
Volume 32, Issue 20, October 2005
How to Cite
2005), Metastable superplumes and mantle compressibility, Geophys. Res. Lett., 32, L20307, doi:10.1029/2005GL024190., and (
- Issue published online: 22 OCT 2005
- Article first published online: 22 OCT 2005
- Manuscript Accepted: 19 SEP 2005
- Manuscript Revised: 7 SEP 2005
- Manuscript Received: 25 JUL 2005
 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.