Abstract
Models of the 3-D mass density variation inside the Earth have been derived for two models of the core-mantle boundary (henceforth referred as CMB): an oblate spheroid and a laterally varying relief. The derived density models significantly differ in mass density compensation. The density model with the CMB modelled as an oblate spheroid fulfils the hypothesis of isostatic compensation, but it does not explain the large-scale dynamic processes in the mantle. The latter model with the aspherical CMB also admits, besides the isostatic compensation in the upper mantle, downgoing and upgoing mass transport in the lower mantle by laterally varying density. This “dynamic” compensation is in a full agreement with the hypothesis of mantle convection. Furthermore, the density perturbations under subduction zones show the penetration of downwelling slabs into the lower mantle, which means that a model of whole mantle convection is favored over stratified convection divided by sharp chemical boundary near the 650-km discontinuity.
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© 1990 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH, Braunschweig
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Martinec, Z., Pěč, K. (1990). The Influence of the Core-mantle Boundary Irregularities on the Mass Density Distribution Inside the Earth. In: Vogel, A., Ofoegbu, C.O., Gorenflo, R., Ursin, B. (eds) Geophysical Data Inversion Methods and Applications. Theory and Practice of Applied Geophysics. Vieweg+Teubner Verlag, Wiesbaden. https://doi.org/10.1007/978-3-322-89416-8_15
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DOI: https://doi.org/10.1007/978-3-322-89416-8_15
Publisher Name: Vieweg+Teubner Verlag, Wiesbaden
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