RheoMan: a five-year, ERC-funded (Advanced Grant), project to model the rheology of the Earth's mantle

Mar 30, 2015 How MgO deforms in the mantle ? Results

New publication in Physics of the Earth and Planetary Interiors with Jonathan Amodeo (Lyon, France), Bernhardt Schuberth and Hans–Peter Bunge (Muenchen, Germany)

The Earth's mantle is characterised by large thermal heterogeneities associated with hot rising plumes and cold downwelling slabs. The lateral temperature variations exceed 1000 K.

 


 

In this paper, we examine the implications of these temperature variations on the rheology of MgO. In particular, we map the transition between the thermally activated and the athermal regime.

In the figure below, coloured areas correspond to regions were dislocation glide in MgO is thermally activated at a depth of 2260 km, with the inferred viscosity:

 

 

 

Reference:

J. Amodeo, B.S.A. Schuberth, H.–P. Bunge, Ph. Carrez & P. Cordier (2015) On the role of thermal heterogeneities on the rheology of MgO under conditions of the Earth’s lower mantle. Physics of the Earth and Planetary Interiors, 242 1-8