Seismic data from central Tibet have been combined to image the subsurface structure and understand the evolution of the collision of India and Eurasia. The 410- and 660-kilometer mantle discontinuities are sharply defined, implying a lack of a subducting slab beneath the plateau. The discontinuities appear slightly deeper beneath northern Tibet, implying that the average temperature of the man...

[1] We study the contribution of mantle flow to surface deformation within the Mediterranean Basin. Flow is modeled numerically based on lateral changes in mantle temperature estimated from tomography models. We find that modeling results are significantly affected by the properties of the selected tomography models. Shear‐velocity models based on surface‐wave observations achieve the highest r...

Three-dimensional modeling of upper-mantle anelastic structure reveals that thermal upwellings associated with the two superplumes, imaged by seismic elastic tomography at the base of the mantle, persist through the upper-mantle transition zone and are deflected horizontally beneath the lithosphere. This explains the unique transverse shear wave isotropy in the central Pacific. We infer that th...

The initial isotopic compositions of Nd and Sr in basalts from the Central Siberian Plateau and other major continental flood basalts are reported. The continental flood basalts appear to be the product of partial melting of mantle sources that consist of relatively primitive undifferentiated material and are clearly distinct from midocean ridge basalts, which sample mantle reservoirs that have...

[1] The shear tractions that mantle flow exerts on the base of Earth’s lithosphere contribute to plate-driving forces and lithospheric stresses. We investigate the sensitivity of these tractions to sub-lithospheric viscosity variations by comparing shear tractions computed from a mantle flow model featuring laterally-varying lithosphere and asthenosphere viscosity with those from a model with l...

We investigate the influence on mantle convection of the negative Clapeyron slope ringwoodite to perovskite and ferro-periclase mantle phase transition, which is correlated with the seismic discontinuity at 660 km depth. In particular, we focus on understanding the influence of the magnitude of the Clapeyron slope (as measured by the Phase Buoyancy parameter, P ) and the vigour of convection (a...

To help determine the chemical composition of the Earth’s mantle, we characterised the high-pressure mineral assemblage of an undepleted natural peridotite—thought to be representative of the Earth’s upper-mantle—to 107 GPa using high-resolution X-ray diffraction. At lower-mantle conditions, the peridotite transforms to the assemblage 76 (F 2)% (Mg0.88Fe0.05 2 + Fe0.01 3 + Al0.12Si0.94)O3 ortho...

BACKGROUND Mantle cell lymphoma (MCL) is an aggressive type of B-cell non-Hodgkin's lymphoma that originates from small to medium sized lymphocytes located in the mantle zone of the lymph node. Extra nodal involvement is present in the majority of cases, with a peculiar tendency to invade the gastro-intestinal tract in the form of multiple lymphomatous polyposis. MCL can be accurately diagnosed...

[1] We show that time‐dependent models of mantle upwellings above a cold downwelling in the New Zealand‐Antarctica region since 80 Ma can explain anomalous geophysical observations: ∼1.0 km of positive residual bathymetry at the Antarctica margin, a large Ross Sea geoid low, 0.5–0.9 km of excess tectonic subsidence of the Campbell Plateau since 80 Ma, and several seismic wave speed anomalies. M...

[1] Abstract: We predict plate motions from a comprehensive inversion of theoretical estimates of tectonic forces in order to evaluate the relative importance of these and the uncertainties of such models. Plate-driving forces from the mantle are calculated using global flow models that are driven by tomography and subduction-derived density fields. Observed and predicted plate velocities agree...