Debris-flow is one of the major geological hazards in southwest China, which are a global threat and happen and results
in thousands deaths and injuries and billions of dollars in damages globally. Automatic multi-temporal DEM coregistration
for detecting terrain changes is an attractive but inherent very difficult research topic. Many methods have
been proposed in recent years, but all of them can only deal with DEM with limited percentage of terrain changes.
However, in landslide and debris-flow areas, the rate of terrain changes is very high. To solve such a problem, a new
method for detecting terrain changes using local invariant patches is proposed in this paper. According to the character of
the debris-flow activities, the peak and ridge are rarely affected. From where some invariant patches can be extracted
associated by the feature extraction method. After co-registration these invariant patches, a coarse matching can be
reached. Therefore, two DEM can be compared after applying this coarse matching. With an appropriate threshold, most
of terrain changes can be eliminated, and then a fine matching can be anticipated reasonable. The accuracy terrain
changes will be derived. The new method can estimate the terrain changes quantificationally and automatically, and
verifies by a real application. The experimental results illustrate the proposed method is of robust, accuracy, and timeefficiency.