The geomorphological status and morphology of rivers and drainage basins are strongly influenced by active tectonic forces, geological structures, and the lithology of a region. By examining the patterns and geometry of stream channels and their associated drainage basins, one can assess and interpret the region's tectonic activity. Quantitative and qualitative morphotectonic analyses are effective tools for identifying the level of tectonic activity in an area; the accessibility of primary data, efficient data collection processes, and the rapid calculation and analysis capabilities have led to the widespread use of these indices in tectonic studies. In this research, three morphotectonic indices—hypsometric integral, drainage basin asymmetry, and basin elongation—were investigated. The results indicate that, for the Tehran Plain drainage basin, the basin elongation index, the hypsometric curve, and the hypsometric integral suggest a mature drainage basin, while the basin asymmetry index points to an asymmetric and tilted basin. An analysis of these morphotectonic indices across sub-basins, combined with the spatial distribution of earthquakes, reveals heterogeneity in both the intensity and the nature of tectonic activity within the Tehran Plain drainage basin. The results indicate that heterogeneous deformations in the eastern (characterized by basin tilting) and western (characterized by basin elongation) sectors coincide with zones of high seismogenic potential. This correlation suggests that the tectonic structures and geological features of the region are the primary controls on the geomorphological processes and the pattern of seismicity within the Tehran Plain drainage basin.

The geomorphological status and morphology of rivers and drainage basins are strongly influenced by active tectonic forces, geological structures, and the lithology of a region. By examining the patterns and geometry of stream channels and their associated drainage basins, one can assess and interpret the region's tectonic activity. Quantitative and qualitative morphotectonic analyses are effective tools for identifying the level of tectonic activity in an area; the accessibility of primary data, efficient data collection processes, and the rapid calculation and analysis capabilities have led to the widespread use of these indices in tectonic studies. In this research, three morphotectonic indices—hypsometric integral, drainage basin asymmetry, and basin elongation—were investigated. The results indicate that, for the Tehran Plain drainage basin, the basin elongation index, the hypsometric curve, and the hypsometric integral suggest a mature drainage basin, while the basin asymmetry index points to an asymmetric and tilted basin. An analysis of these morphotectonic indices across sub-basins, combined with the spatial distribution of earthquakes, reveals heterogeneity in both the intensity and the nature of tectonic activity within the Tehran Plain drainage basin. The results indicate that heterogeneous deformations in the eastern (characterized by basin tilting) and western (characterized by basin elongation) sectors coincide with zones of high seismogenic potential. This correlation suggests that the tectonic structures and geological features of the region are the primary controls on the geomorphological processes and the pattern of seismicity within the Tehran Plain drainage basin.