# Mapping the lower mantle: Determination of lateral heterogeneity in P velocity up to degree and order 6

@article{Dziewoski1984MappingTL, title={Mapping the lower mantle: Determination of lateral heterogeneity in P velocity up to degree and order 6}, author={Adam M. Dziewoński}, journal={Journal of Geophysical Research}, year={1984}, volume={89}, pages={5929-5952} }

The data from the International Seismological Centre bulletins for the years 1964–1979 are used to derive a three-dimensional model of lateral variations of the P velocity in the lower mantle. Unlike previous studies, in which such perturbations were represented by a blocklike parameterization, we seek the solution in the form δυ(r, θ, ϕ) = Σk = 0K Σl = 0L Σm = 0l ƒk(r)(kAlm cos mϕ + kBlm sin mϕ) plm (cos θ). Some 500,000 travel time residuals for teleseismic distances from 5000 earthquakes are…

## 754 Citations

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