Iceland is located where the asthenosperic flow under the the NE Atlantic plate boundary interacts and mixes with a deep-seated mantle plume. The buoyancy of the Iceland plume leads to dynamic uplift of the Iceland plateau, and high volcanic productivity over the plume produces a thick crust. (Fig.1). The Greenland-Færöy ridge represents the Icland plume track through the history of the NE Atla...

The method proposed by Mooney and Steg (1969) for obtaining the dilatational dependence of the Gr0neisen parameter from data on the pressure dependence of the thermal conductivity (or, equivalently, thermal diffusivity) is critically examined and applied to thermal diffusivity data for sodium chloride and quartz. The values obtained are ?o'(--(d?/dA)la_-o) = 3.0 for sodium chloride and 7o' = 2....

The postperovskite (ppv) phase transition occurs in the deep mantle close to the core-mantle boundary (CMB). For this reason, we must include in the dynamical considerations both the Clapeyron slope and the temperature intercept, T(int), which is the temperature of the phase transition at the CMB pressure. For a CMB temperature greater than T(int), there is a double crossing of the phase bounda...

A thin-shell program for modeling neotectonics of regional or global lithosphere with faults. Influence of fore-arc structure on the extent of great subduction zone earthquakes. 1994: Effects of multiple phase transitions in a three-dimensional spherical model of convection in Earth's mantle. 2000: Role of temperaturedependent viscosity and surface plates in spherical shell models of mantle con...

Dense record sections from deep earthquakes in Fiji and Argentina recorded on hundreds of short-period stations in California at distances of 81 o to 85° are used to investigate the detailed P wave velocity structure above the core-mantle boundary (CMB). In the Fiji data a secondary phase arriving 2 to 4 s after the direct P is identified as a precursor to PeP. This phase provides good evidence...

[1] The electrical conductivity of mantle minerals is highly sensitive to parameters that characterize the structure and state of the lithosphere and sublithospheric mantle, and mapping its lateral and vertical variations gives insights into formation and deformation processes. We review state‐of‐the‐art conductivity models based on laboratory studies for the most relevant upper mantle minerals...

We review the present state of our understanding of mantle convection with respect to geochemical and geophysical evidence and we suggest a model for mantle convection and its evolution over the Earth's history that can reconcile this evidence. Whole-mantle convection, even with material segregated within the D" region just above the core-mantle boundary, is incompatible with the budget of argo...

We explore the nonlinear dynamics of a forced core-mantle system. We show that the free axisymmetric motion of a uniform-vorticity Ñuid core coupled to a rigid mantle (the model) is Poincare -Hough integrable. We derive an approximate Hamiltonian for the core tilt mode that includes the leading nonlinear contribution. We then include gravitational perturbations in the analysis. We identify the...

Understanding the deformation mechanisms of olivine is important for addressing the dynamic processes in Earth's upper mantle. It has been thought that dislocation creep is the dominant mechanism because of extrapolated laboratory data on the plasticity of olivine at pressures below 0.5 GPa. However, we found that dislocation-accommodated grain boundary sliding (DisGBS), rather than dislocation...