Testing the dynamic coupling of the core‐mantle and inner core boundaries
DOI: 10.1002/2014JB011682
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摘要: The proposal that the seismically observed hemispherical asymmetry of Earth's inner core is controlled by heat flux structure imposed on outer lower mantle tested with numerical dynamo models driven mixed thermochemical convection. We find a single core-mantle boundary (CMB) spherical harmonic degree and mode 2, dominant in seismic shear velocity tomography, produce similar at (ICB) shifted 30∘ westward. sensitivity ICB to CMB further increasing heterogeneity amplitude. In addition, two tomographic are tested: first resolution up order 4, second 8. time-averaged these cases be large scale, small-scale differences due higher harmonics (above 4). “Earth-like” magnetic fields, while twice flow amplitudes less Earth-like implying forces model out an regime. dynamic fluxes compared proposed translation test whether controls growth structure. This indicates that, although tomography unlikely driving translation, response weak enough not interfere most unstable mode, if it occurring.
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