Inversion results and data fit for three different grid points in NE China. These estimated models and data fits shown here correspond to grid nodes located in (a) Jiamusi block (127°N, 43°W), (b) Songliao block (124°N, 46°W) and (c) Xing'an block (119°N, 47°W). The left panels show measured dispersions (circles with error bars) and theoretical dispersions calculated from the final models. The right panels show the reference (dashed line) and final (solid line) models for two different initial models: SEAPS model (black) and RFM model (gray).