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Evidence for deep mantle circulation from global tomography

R. D. Van Der Hilst·S. Widiyantoro·E.R. Engdahl
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Abstract

Seismic tomography based on P-wave travel times and improved earthquake locations provides further evidence for mantle-wide convective flow. The use of body waves makes it possible to resolve long, narrow structures in the lower mantle some of which can be followed to sites of present-day plate oonvergence at the Earth's surface. The transition from subduction-related linear structures in the mid-mantle to long-wavelength hetorogeneity near the core-mantle boundary remains enigmatic, but at least some slab segments seem to sink to the bottom of the mantle.

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R. D. Van Der Hilst, S. Widiyantoro, E.R. Engdahl. 1997. Evidence for deep mantle circulation from global tomography. https://doi.org/10.1038/386578a0

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