Topographic Fingerprints of Tectonic Deformation in the Zurbatiyah Region, Eastern Iraq: A Multi-Index DEM-Based Analysis

ABSTRACT This work conducts a morphotectonic analysis using the Topographic Position Index (TPI), Slope, Curvature, and Terrain Ruggedness Index (TRI) to elucidate the relationship between geomorphic indices and tectonic processes. ALOS PALSAR DEM data with a resolution of 12.5 meters were used in TPI applications for a 50-meter radius, where landforms and structural landform patterns were categorized. In an ArcGIS environment, Slope and Curvature maps and TRI, which assessed the relationship between fault zones and elevated blocks, were analyzed to evaluate terrain inclination, morphology, and roughness. The composite index, including TRI, slope, and curvature, effectively identified areas of geomorphic instability and morphotectonic boundaries at a regional level. The topographic class distribution revealed NW-SE oriented high ridges and axial troughs connected with folding and fault structures. Active thrusts and anticlines dominated steep slopes and regions of positive curvature, whilst the western sector, characterized by a low gradient, remained inactive. The combined strategy, with other methodologies, effectively enhanced the detection of neotectonic features and surface deformation dynamics. The method relies on understanding the landscapes’ geomorphology evolution under the influence of tectonics in regions with intricate structure.