2026 Volume 18 Issue 2 Pages 18-27
Understanding underground structures, such as the thickness and stiffness of soil layers, is important for earthquake disaster prevention. There are two main ways to investigate underground structures: excavation survey and non-destructive survey. Among non-destructive methods to investigate underground structures, we focused on the surface wave survey and the method applying seismic interferometry to continuous microtremor records. The former has been well established and widely used, while the latter is still under consideration. In this study, we applied and compared the two methods on the same survey line. The result shows that surface wave survey provide higher resolution in relatively higher frequency, corresponding to shallower zone. On the other hand, the seismic interferometry offers higher resolution in relatively lower frequency, corresponding to deeper zone. The subsurface structure was not clearly revealed in this study. However, it may be estimated for wide depth range by combining the existing surface wave survey technique and the method applying the seismic interferometry to microtremor records under appropriate condition.
