The impact of digital elevation models resolution on tectonic activity assessment based on morphotectonic indices: a case study of Seulawah Agam Volcano, Indonesia

The Digital Elevation Number (DEM) is the main tool for quantitative geomorphological tests. Furthermore, Shuttle Radar Topography Mission (SRTM) images with a resolution of 30 m have been widely used as source DEM data in studies, while DEMNAS (National DEM) 8 are rarely used. Both can identify typical volcanic morphology based on visual comparison hillshade certain variations slope. objective this study was to determine feasibility tectonic activity assessment morphotectonic indices. In study, comparisons were carried out twelve watersheds Seulawah Agam Volcano (SAV). extraction resulted total area and perimeter, namely 486.8 km<sup>2</sup> 455 km (SRTM), well 482.8 460.3 (DEMNAS). segments up 4<sup>th</sup> order resulting lengths 290 512.8 SRTM, 527 711.7 km. variables included drainage density, bifurcation, circularity, valley floor ratio, basin shape index. results these parameter calculations using mean values SRTM imagery showed very coarse textures, deformed, more elongated, moderate tectonic, low uplift. On other hand, those not-deformed, uplift basin’s characteristics.