Comparison of classification methods on geomorphometric data of Peteroa volcano area

Four different geomorphometric classifications of local topographic gradients for the Peteroa Volcano area are introduced and compared. The compared methods are Isodata, Tandem Analysis on correlation and covariance matrices, and the segmentation following a Hierarchical Factorial Classification of gradients. Input data are obtained by processing a raster Digital Elevation Model extracted from ASTER stereo-pairs. The resulting maps show the spatial distribution of homogeneous landform units, highlighting the impact of erosional and tectonic processes on the whole relief. Moreover, each class is being described by either mean gradient values or mean topographic attributes such as elevation, slope and aspect. Next, these data are interpreted in terms of morphological setting.