Fig. 5

Example of the data selection process. The orange dots show data excluded using the global CMT catalog (Ekström et al. 2012), and the blue dots show data transients when the amplitude changes suddenly. The black dots represent selected segments. The vertical axis shows the relative power normalized by the Peterson NLNM (Peterson 1993)), which represents the lowest ground noise on Earth. Taken from Nishida and Takagi (2022)