抄録
A method of analyzing the aerial photograph of the landslide area has been developed to extract the area covered with the deposit by the past landslide or collapse, which is known to be in danger of the secondary land-slide or collapse. In this method, the image of aerial photograph is analyzed by measuring the light intensity reflected on the surface of aerial photograph. It is found that on sweeping the image the light intensity change with many oscillations of with period are smaller than the area of landslide and collapse. The block of landslide can be extracted from the image analysis, because the amplitudes of the oscillations in the block of landslide are appreciably different from the area which has sufferad no landslide. In the interior of the past landslide mass, the pulse oscillations are observed at the deforming and crashing ground.
