Detection of Slope Failures Including Shadow Area Using High Resolution Satellite Images

Abstract

In most case of steep mountainside in Japan, slope failures are extending both sunny area and shadow area. To assess the actual disaster, accurate and reliable detection has to be required. Therefore the detection has to be able to estimate failures in the shade. In this study, a slope failure detector based on region growing algorithm is proposed for high-resolution satellite images. It calculates the magnitude and the morphology after the detection of failures in sunny area. The method was applied to detection of heavy rainfall induced slope failures in the upstream of the Yahagi River triggered by the Tokai Heavy rainfall, 2000. The conclusion is shown as follows:
(1) Most of sliding failures can be detected precisely using a threshold value.
(2) The shaded relief processing was effective to detect the debris flow failure along a valley, and the accuracy was improved.