EA17
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EA17 is a regional model of East Asia developed on a ~0.35 degree tessellated icosahedral grid, and is provided as a set of 1D model files in the MINEOS format. The 1-D models are located at the original grid nodes, with the longitude and latitude found on the first line of each model file. This type of tesselated icosahedron was fist used in spherical-Earth modeling by Baumgardner et al. (1985) and Wang and Dahlen (1995), who used a spherical spline parameterization. Linear interpolations between values at icosahedral grid nodes were independently implemented by Constable et al. (1993) in geomagnetic modeling and by Van der Lee and Nolet (1997) in seismic tomography.
EA17 was generated by an inversion of localized Rayleigh group and phase velocity dispersion curves, with respect to 16 1D reference models found through a cluster analysis of 2D group velocity maps. Please read Witek et al. (2018) for pertinent details, of which a mere few are summarized here.
Ambient noise group velocity data is used in the period range 6-40 s, and earthquake group and phase velocity data is used in the period ranges 50-133.33 s and 28.57-200 s, respectively. The earthquake group and phase velocity data were taken from the global dispersion model of Ma et al. (2014). More details about EA17 can be found in Witek et al. (2018).
You can also (just) download the reference/starting/prior Moho model (10 Mb).
Reference:
Witek, M., S. van der Lee, T.-S. Kang, S.-J. Chang, J. Ning, and
S. Ning (2018). S-velocity model of East Asia from a cluster analysis
of localized dispersion. J. Geophys. Res., doi: 10.1029/2018JB016060, 2018.
Other references:
Baumgardner, R.B. and P.O. Frederickson, Icosahedral discretization
of the two-sphere. SIAM J. Numer. AnM., 22, 1107-1115, 1985.
Constable, C. G., R. L. Parker and P. B. Stark, Geomag- netic field
models incorporating frozen-flux constraints, Geophys. J. Int.,
113, 419-433, 1993.
Ma, Z., Masters, G., Laske, G., & Pasyanos, M., A comprehensive
dispersion model of surface wave phase and group velocity for the
globe. Geophysical Journal International, 199(1), 113-135, 2014.
Van der Lee, S. and G. Nolet, Upper-mantle S-velocity structure of
North America, J. Geophys. Res., 102, 22,815-22,838, 1997.
Wang, Z., and F. A. Dahlen, "Spherical-spline parameterization of
three-dimensional Earth models", Geophysical Research Letters 22,
no. 22: 3099-3102, 1995.