Assessment of Relative Tectonic Activity Using Morphotectonic Analysis in the Central High Atlas, Demnate Region, Morocco

This study focuses on the morphotectonics of the Central High Atlas in Morocco through analysis of morphotectonic indices recorded by topography, drainage networks, and longitudinal stream profiles. The methods used in this work were stream length-gradient index (SLI), normalized steepness index, area-altitude relations (hypsometric curves), mountain front sinuosity, drainage basin shape ratio, and asymmetry factor. The aim is to identify the role of recent tectonic activity resulting in the uplift of the Atlas chain in general and the Central High Atlas in particular. The analysis of the main rivers in the study area using linear geomorphic proxies revealed the presence of several knickpoints (about 28) most likely related to recent tectonic activity; further, the spatial distribution of SLI values reveals the presence of many anomalous zones, which are distinguished by elevated values that are perfectly aligned with major faults. The calculation of areal geomorphic proxies supports and confirms these findings. The results obtained show that the study area has been influenced by recent tectonics, and that some areas of the Central High Atlas have experienced a recent uplift due probably to a reactivation of several thrust and oblique-slip faults, then the high topography can be explained by a compressive component of the transpressional geodynamic regime suggested in the Plio-Quaternary period.