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The purpose of this work is to compare kinematics of small-scale currentvortices located near the core-mantle boundary with high-speed anomalies ofseismic wave velocity in the lowest mantle asso-ciated with the subductionzones. The small-scale vortex paths were early obtained by the authors in theframe of the macro model of the main geomagnetic field sources. Two sourceswere chosen whose kine-matics are characterized by the complete absence of thewestern drift and whose paths have a very com-plex shape. Both sources arelocated in the vicinity of the subduction zones characterized by the extensivecoherent regions with increased speed of seismic waves in the lowest mantle.One of them is geographically located near the western coast of Canada and thesecond one is located in the vicinity of Sumatra. For this study we used theglobal models of the heterogeneities of seismic wave velocity. It was obtainedthat the complex trajectories of the vortices is fully consistent with thehigh-speed anomalies of seismic wave velocity in the lowest mantle. It can beassumed that mixing up with the matter of the lowest mantle, the substance ofthe liquid core rises along the lowest mantle channel and promotes its furtherincrease. In addition, the volume of oceanic crust, subducted millions of yearsago, turned out to be sufficient to penetrate into the liquid core, forming thecomplex shape restrictions for free circulation of the core liquid.

Subduction Zone Effect on the Structure of the Small-Scale Currents at Core-Mantle Boundary