Fig. 4From: Directionally dependent horizontal-to-vertical spectral ratios of microtremors at Onahama, Fukushima, JapanComparison of MHVRs along Line-3 shown in Fig. 2a. The figures from top-left to bottom-right are aligned from south to north on the survey line. Red and blue lines indicate NS/UD and EW/UD, respectively. The difference between the two is significant for points 3-7 to 3-9. The value of γ for each point is denoted in the right-top cornerBack to article page