Smoothed basin velocity structure model of the Kanto Sedimentary Basin (Takemura et al., 2015)

Model description

We constructed sedimentary S-wave velocity structure model of the Northern Kanto region using 190 local S-wave velocity structures. In the uploaded files of Takemura2015_V0..dat and Takemura2015_Alpha.dat, longitudes, latitudes and values of \(V_0\) (and \(\alpha\)) at 190 local points are listed. Our model of the sedimentary basin was described by two parameters of  a simple velocity gradient function (Ravve and Koren 2006). The depth gradient function is described as

\(V_S(z)=V_0+\Delta V\left[1-\exp\left(-\frac{\alpha z}{\Delta V}\right)\right]\)

where \(V_0\) is the S-wave velocity at the surface (z = 0), \(\Delta V\) is S-wave velocity of the bedrock (3.2 km/s), and \(\alpha\) is the positive constant that determines the velocity-depth gradient.

3D sedimentary model construction 

After applying GMT surface to each parameter, spatial variations of both two parameters were obtained. Using obtained spatial distributions of \(V_0\) and \(\alpha\) and the depth gradient function, 3D sedimentary velocity structure of the Northern Kanto region could be constructed. 

Citation

Takemura, S., Akatsu, M., Masuda, K., Kajikawa, K., & Yoshimoto, K., (2015), Long-period ground motions in a laterally inhomogeneous large sedimentary basin: observations and model simulations of long-period surface waves in the northern Kanto Basin, Japan, Earth, Planets and Space, 67:33, doi:10.1186/s40623-015-0201-7