Close spacing of multiple 2-D Vs maps makes it possible to use them for the construction of a 3-D (cubic) data set through a proper 3-D interpolation scheme (Fig. 1). Considering the fact that only plane-wave components are selectively processed during the dispersion imaging process for a 2-D profile, and all other offline waves such as side scatterings are exclusively suppressed, this independent use of each 2-D profile for the 3-D spatial interpolation can be a valid processing, producing 3-D data in the simplest manner (Park and Carnevale, 2009). Display of 2-D slices extracted from this cubic data set along three orthogonal axes (x, y, and z) can be a highly effective tool to understand the 3-D elastic characteristics of the site (Fig. 2).
