DEM generation from ASTER satellite data for geomorphometric analysis of Cerro Sillajhuay (Chile/Bolivia)

Digital elevation models (DEMs) are increasingly used for visual and mathematical analysis of topography, landscapes and landforms, as well as modeling of surface processes. A DEM of Cerro Sillajhuay, a volcano in the Andes of Chile/Bolivia, was developed from ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite data. The original 30-m DEM was generated by using tie points, and was finally re-sampled to 15 m to exploit full ortho-image resolution. Five geomorphic parameters, which are useful to identify and describe geomorphologic forms and processes, were extracted using the software ArcInfo and ArcView: elevation, aspect, slope angle, vertical curvature, and tangential curvature. Although the elevation values are slightly to low in altitudes above 5500 m asl., the ASTER DEM is useful for an interpretation of the macro-and mesorelief, and provides the opportunity for mapping especially at medium scales (1: 100,000 and 1: 50,000).