Evaluation of tectonic activity using morphometric indices: Study of the case of Taïliloute ridge (middle-Atlas region, Morocco)

Abstract

In the Middle Atlas region, the Tizi N'Teghtène Fault System is a network of faults inherited from the Hercynian orogeny, which operated as normal faults during the Jurassic and reverse faults since the Miocene. The issue at hand is whether this fault system continues to be active today. To address this concern, focus has been placed on a central portion of the Tizi N'Teghtene Fault System, specifically the anticlinal ridge of Taïliloute. Determining the tectonically active segments of this ridge is crucial for structural analysis and the Quaternary evolution of this mountain chain. To achieve this, morphometric indices related to the evolution of watersheds and their streams have been employed. These indices include hypsometry, elongation ratio (Re), drainage asymmetry factor (AF), and the elongation profiles of various watercourses. These indicators provide insights into the degree of active longitudinal growth of the Taïliloute ridge. These parameters were determined through satellite image analysis using suitable software and geographic information systems (GIS). Tectonic activity analyses reveal that both flanks of this ridge exhibit ongoing tectonic activity, marked by the occurrence of normal faults and strike-slip faults during the Quaternary phase of the Alpine orogeny. It is concluded that the Tizi N'Teghtene Fault system remains tectonically active. This research contributes to a deeper understanding of the ongoing tectonic activities within the Tizi N'Teghtene Fault System, a matter of geological significance. By employing morphometric indices ad modern satellite image analysis techniques, a methodological innovation is presented by this study in assessing tectonic activity in mountainous regions. These results provide valuable insights into structural dynamics of the Middle Atlas, aiding in the understanding of its geological evolution. Furthermore, this research can have broader applications in seismic hazard assessment and land use planning, making it relevant beyond the immediate geographical boundaries of the study area.