Metastable superplumes and mantle compressibility
- 22 October 2005
- journal article
- Published by American Geophysical Union (AGU) in Geophysical Research Letters
- Vol. 32 (20)
- https://doi.org/10.1029/2005gl024190
Abstract
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.This publication has 24 references indexed in Scilit:
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