The deformation at the core-mantle boundary produced by the 2004 Sumatra earthquake is investigated by means of a semi-analytic theoretical model of global coseismic and postseismic deformation, predicting a millimetric coseismic perturbation over a large portion of the core-mantle boundary. Spectral features of such deformations are analysed and discussed. The time-dependent postseismic evolut...

Seismic observations recorded by an African seismic array reveal a low velocity anomaly at the base of the mantle beneath the Indian Ocean, with steeply dipping edges, rapidly varying thicknesses and geometries, and anomalously low shear wave velocities decreasing from 32% at 200 km above the core^mantle boundary to 39% to 312% at the core^ mantle boundary (relative to the preliminary reference...

The possibility of reaction between the liquid iron of the Earth's outer core and crystalline silicates ((Mg, Fe)SiOa) of the mantle, MgO., Feo.•SiOa(pv) + O.15Fe(e) = 0.9MgSi03 (pv)+O.2FeO(hpp)+O.O5FeSi(•)+ O.05Si02(st), was proposed by Knittie and Jeanloz(1989,1991) on the basis of exploratory experiments. We calculate Gibbs free-energies for the reactants and the products of the above reacti...

recently, the s receiver function method has been successfully developed to identify upper mantle interfaces. s receiver functions have the advantage of being free of s-wave multiple reflections and can be more suitable than p receiver function for studying mantle lithosphere. however, because of specific ray geometry of the s-to-p converted waves, the s receiver function method has some techni...

[1] An SH hybrid method is developed for calculating synthetic seismograms involving twodimensional localized heterogeneous structures. The hybrid method is a combination of analytic and numerical methods, with the numerical method (finite difference) applied in the heterogeneous region only and analytical methods applied outside the region. Generalized ray theory solutions from a seismic sourc...

a r t i c l e i n f o Keywords: mantle plumes phase transitions temperature dependent viscosity thermal expansivity lattice thermal conductivity Recent high-resolution seismic imaging of the transition zone topography beneath the Hawaiian archipelago shows strong evidence for a 1000 to 2000 km wide hot thermal anomaly ponding beneath the 660 km boundary west of Hawaii islands [Q. Cao et al. Sei...