A New Method for Calculating the Volume of Debris Flow Using GIS and RS Technology

In this paper, two digital elevation models of debris flow in Yingxiu mountain area are generated; one is from contour lines with manual interpretation before earthquake and the other is from high resolution aerial photos using MapMatrix software. By analyzing three random points which are not in the same edge, a new formula for calculating the volume from these three points to their projection on the datum plane is derived. Then, the volumes of the two DEMs before and after earthquake can be calculated, and the volume of the total debris flow is the difference of those two.