Present-day continental extension along the East African Rift System (EARS) has often been attributed to diverging sublithospheric mantle flow associated with the African Superplume. This implies a degree of viscous coupling between mantle and lithosphere that remains poorly constrained. Recent advances in estimating present-day opening rates along the EARS from geodesy offer an opportunity to ...

Interrogating physical processes that occur within the lowermost mantle is a key to understanding Earth's evolution and present-day inner composition. Among such processes, partial melting has been proposed to explain mantle regions with ultralow seismic velocities near the core-mantle boundary, but experimental validation at the appropriate temperature and pressure regimes remains challenging....

[1] Reconstructing the thermal history of the Earth, consistent with the low concentration of heat-producing elements in convecting mantle as well as with modest secular cooling required by geological records, has been a major challenge in geophysics and geochemistry. By developing the self-consistent energetics of plate-tectonic mantle convection, we show that the low Urey ratio of convecting ...

The objectives of this study were to investigate color patterns of shell and mantle edge pigmentation of a Pacific oyster, C. gigas, and to estimate variance components of the two colors. A sample of 240 F0 oysters was collected from six aquaculture farms in Tongyeong, Korea to measure shell color and mantle edge pigmentation. Among the F0s, male and female individuals with black (white) shell ...

The frequent formation of large igneous provinces during the opening of the Atlantic Ocean is a surface manifestation of the thermal and chemical state of convecting mantle beneath the supercontinent Pangea. Recent geochemical and geophysical findings from the North Atlantic igneous province all point to the significant role of incomplete mantle mixing in igneous petrogenesis. On the basis of a...

1. A preparation of the mantle of Octopus which is inverted over a solid support and which exposes the stellate ganglion and associated nerves is described. 2. Afferent activity can be recorded from stellar nerves following electrical stimulation of the pallial nerve. The latency and frequency of the phasic sensory response is correlated with the contraction of the mantle musculature. 3. It is ...

 The effects of seasons on lipid and fatty acid profiles of muscle types (mantle and arm) of Mediterranean octopuses (common octopus-Octopus vulgaris and musky octopus-Eledone moschata) were investigated. The results showed that lipid levels ranged from 0.75% to 1.60% in both muscle types of octopuses which were considered as lean. Lipid levels in mantle tissues of both octopus species w...

S U M M A R Y A 3-D finite-element simulation of global electromagnetic induction is used to evaluate satellite responses in geomagnetic dipole coordinates for harmonic ring-current excitation of a threelayer mantle overlain by a realistic near-surface conductance distribution. Induced currents are modelled for lithospheric and asthenospheric upper-mantle conductivities in the range σ = 10−4–0....

The discovery of a phase transition in Mg-rich perovskite (Pv) to a post-perovskite (pPv) phase at lower mantle depths and its relationship to D′′, lower mantle heterogeneity and iron content prompted an investigation of the relative importance of lower mantle compositional and temperature fluctuations in creating topographic undulations on mixed phase regions. Above the transition, Mgrich Pv m...

Computer models of mantle convection constrained by the history of Cenozoic and Mesozoic plate motions explain some deep-mantle structural heterogeneity imaged by seismic tomography, especially those related to subduction. They also reveal a 150-million-year time scale for generating thermal heterogeneity in the mantle, comparable to the record of plate motion reconstructions, so that the probl...