Published in Izvestiya, Physics of the Solid Earth
Abstract—Based on the alpha-shape computer-graphics analysis of coda envelope of the waves from nuclear explosions reflected from the inner core boundary (PKiKP), the estimates of the mechanical Q-factor are obtained for nine reflection regions beneath the Arctic, Central, and Southeast Asia with the average Q = 447 ± 43. The coda formation mechani...
Published in Izvestiya, Physics of the Solid Earth
Abstract—The paper presents the review of the conceptually most important results of seismological studies of the Earth’s core and their interpretation from the standpoint of geodynamics in three directions: anisotropy of seismic velocities and seismic attenuation, structural features of the transition zone between the outer and inner core, and dif...
Seismic observations of a slowdown in P wave velocity at the base of Earth's outer core suggest the presence of a stably-stratified region known as the F-layer. This raises an important question: how can light elements that drive the geodynamo pass through the stably-stratified layer without disturbing it? We consider the F-layer as a slurry contai...
The outermost part of the inner core is isotropic, though the thickness of this layer varies longitudinally, commonly interpreted to be a zone where compaction of the crystallites randomly adhering to the inner core boundary eventually aligns them. We explore the possibility that the surface layer is also anisotropic, but of a form that thwarts det...
Published in Materials
The PELE (penetration with enhanced lateral efficiency) projectile is a new type of safe ammunition which can form a large number of fragments after perforating the target, and does not depend on any pyrotechnics. The damage characteristics of PELE projectile mainly include the penetration ability and fragmentation effect. There are many factors af...
Published in American Mineralogist
Carbon has been suggested as one of the light elements existing in the Earth’s core. Under core conditions, iron carbide Fe7C3 is likely the first phase to solidify from a Fe-C melt and has thus been considered a potential component of the inner core. The crystal structure of Fe7C3, however, is still under debate, and its thermoelastic properties a...
Published in American Mineralogist
The sound velocity of hcp Fe0.89Si0.11 (Fe-6wt% Si) alloy was measured at pressures from 45 to 84 GPa and temperatures of 300 and 1800 K using inelastic X-ray scattering (IXS) from laser-heated samples in diamond-anvil cells (DACs). The compressional velocity (νP) and density (ρ) of the Fe-Si alloy are observed to follow a linear relationship at a ...
Published in Journal of Applied Mechanics and Technical Physics
Steady flow generated by oscillations of an inner solid core in a fluid-filled rotating spherical cavity is experimentally studied. The core with density less than the fluid density is located near the center of the cavity and is acted upon by a centrifugal force. The gravity field directed perpendicular to the rotation axis leads to a stationary d...
We computed interior structure models of Mercury and analyzed their viscoelastic tidal response. The models are consistent with MErcury Surface, Space Environment, GEochemistry, and Ranging mission inferences of mean density, mean moment of inertia, moment of inertia of mantle and crust, and tidal Love number k2. Based on these constraints we predi...
The mechanical properties of C-doped hexagonal close-packed (hcp) iron are studied at high pressure from first-principles calculations. The energy required for doping with C as an interstitial impurity is 246meV/1wt%C at 120GPa for one unit cell of hcp Fe and increases almost linearly with pressure. The density deficit of the inner core can be matc...
