Tomography Model
Tomography Model
Tomography Model
D'' discontinuity
Low Velocity Province at the CMB
Weighting Scheme

New Global SH Velocity Model (SH18CEX) 

Waveform tomography is conducted for SH velocity structures of the entire mantle using approximately 3.5 times the data used for obtaining the previous model, SH18CE. The resultant new model, SH18CEX, exhibits a cluster of ridge-like low-velocity anomalies in the western part of the Pacific Large Low-Shear-Velocity Province (LLSVP). The location of the ridge-like anomalies is in good agreement with the location of the abrupt change in the topography of the D'' discontinuity. These results suggest that the LLSVP is associated with a cluster of ridge-like-piles, rather than a single large pile spread over the entire region. The piles probably consist of intrinsically dense material; however, either their volume or density contrast may not be sufficiently large to develop large-scale domes.

download the model parameters (sh18cex.tar.gz)
mapview of the model SH18CEX (1)
mapview of the model SH18CEX (2)

  • Takeuchi, N., 2012.  Detection of ridge-like structures in the Pacific Large Low-Shear-Velocity Province, Earth Planet. Sci. Lett., in press.
  • Takeuchi, N., 2007.  Whole mantle SH velocity model constrained by waveform inversion based on three-dimensional Born kernels, Geophys. J. Int., 169, 1153-1163.

older model (SH18CE)