GROUND DISPLACEMENT DETECTION BY AERIAL-PHOTOGRAPHS-BASED DIGITAL SURFACE MODEL OF THE 2016 KUMAMOTO EARTHQUAKES

摘要

An obvious ground displacement has occurred in disaster-affected area along the Futagawa fault in the 2016 Kumamoto earthquakes. In this research, two digital surface models (DSMs) generated from high-resolution Aerial Digital Sensor (ADS) on April 15 (before the mainshock on April 16) and April 19 (after the mainshock on April 16) were used to demonstrate the practicability of ground displacement calculation through the pixel-offset analysis. The calculation of horizontal ground displacement was based on the comparison between the two DSMs by cross-correlation coefficient. The vertical ground displacement was obtained from the difference between the two DSMs, with the post-mainshock DSM where the horizontal ground displacement has been shifted back precisely. The result showed that there is an acceptable consistency with the ground displacement data obtained by the previous related research and the trend of Futagawa fault line.