Fig. 4: HVSR information and velocity models.
From: Subsurface structure and impact process of Yilan Crater, northeastern China
a Distribution of the observed fundamental frequency (f0) across the investigated area. b HVSR curves from three selected stations YL0718, YL0710, and YL0000. c Velocity models at the center of crater inverted by fitting the dispersion curve with different reference models (Supplementary Fig. 9). The shaded area marks the velocity contrast that most likely corresponds to the sediment-rock transition. d Empirical relationships between fundamental frequency and sediment thickness. Station YL0000 behaves as the benchmark to determine the appropriate bounding relationships. (for further detail, please see Qin et al.10 and references therein).
