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}
}
  • A. Dziewoński
  • Published 10 July 1984
  • Geology
  • Journal of Geophysical Research
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… 
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References

SHOWING 1-10 OF 30 REFERENCES
Determination of the three‐dimensional seismic structure of the lithosphere
A new three-dimensional earth modeling is proposed as a framework to obtain more detailed and accurate information about the earth's interior. We start with a layered medium of classic seismology but
Mapping the upper mantle: Three‐dimensional modeling of earth structure by inversion of seismic waveforms
A method is presented for the inversion of waveform data for the three-dimensional distribution of seismic wave velocities. The method is applied to data from the global digital networks
Travel-time inversion for simultaneous earthquake location and velocity structure determination in laterally varying media
Summary. Travel times are observed at a network of seismometers from a number of earthquakes. The seismic velocity of the medium through which the waves pass is allowed to vary in all three
Large‐scale heterogeneities in the lower mantle
Coefficients of a spherical harmonic expansion, up to angular order 3, of velocity anomalies in five shells within the earth's mantle were obtained from an analysis of nearly 700,000 P wave travel
P-wave travel times from deep earthquakes
A study of teleseismic P -wave travel times has been made using data from deep (450 to 650 km) earthquakes exclusively, for which the effect of near-source upper mantle heterogeneity is expected to
Phase velocities of long‐period surface waves and structure of the upper mantle: 1. Great‐Circle Love and Rayleigh wave data
New long-period dispersion data are obtained from the surface waves generated by the Alaska earthquake of March 28, 1964, and recorded at Isabella, Kipapa, and Stuttgart. Digital techniques were used
An analysis of the travel times of P waves to North American Stations, in the distance range 32° to 100°
abstract Travel times of P waves from 25 earthquakes to stations in North America, in the distance range 32° to 100°, have been analyzed by a least squares technique similar to the “time term” method
Measurement of mantle wave velocities and inversion for lateral heterogeneity and anisotropy: 1. Analysis of Great Circle Phase Velocities
Long-period (100–330 s) fundamental-mode Love and Rayleigh waves have been processed to measure the great circle phase velocities for about 200 and 250 paths, respectively. The observations are
Fundamental spheroidal mode observations of aspherical heterogeneity
Summary. Accelerograms from the IDA network have been processed to obtain 2193 multiplet locations (apparent centre frequencies) for the fundamental spheroidal modes 0S5-0S43- Great circles
...
1
2
3
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