Fig. 19

N–S displacement and strain field around the northwest of outer rim of Aso caldera. a Map of difference between the N–S component of horizontal displacement along each displacement lineament, which corresponds to the N–S opening displacement of each displacement lineament. Red and blue lines indicate the displacement lineaments with dip-slip open and close motion, respectively. b Strain field calculated using ALOS-2 data. Red and blue arrows indicate extension and contraction, respectively; the background color (blue-to-red) represents dilatation