Fig. 4

Station coordinate time series at a MAC1, b MAS1, c MATE, and d YELL with respect to the IGS combined solution. Their approximate positions are plotted in e. The 28-day moving average was plotted by the solid lines. The daily coordinates of F5 were also plotted by the dots. Each AC’s time series was drawn with a constant interval of 1 cm for clear visibility. ULR was eliminated because the temporal variation was too large to draw a consistent scale