Morpho-tectonic hazard zonation over rift shoulder domains utilizing geomorphic indices and seismicity data: an example from Wadi Ghweiba Basin, Northwestern Gulf of Suez coast, Egypt

Abstract This study investigates the hydrographic watershed of Wadi Ghwaiba Basin (WGB), a key drainage system in Egypt’s Eastern Desert, situated northwest of the Gulf of Suez (GOS). While Gulf of Suez Rifting (GOSR) tectonics are known to impact the region, their influence, especially neotectonics, on drainage development is understudied. Using GIS and a DEM, we analyzed the WGB’s drainage system and derived geomorphic variables. We assessed WGB tectonic processes via five geomorphic parameters (GPs) and current seismicity data. Sub-basin catchments were categorized by their morphometric characteristics. By integrating seismic epicenter magnitudes with spatial morphometric maps, we developed a comprehensive morpho-tectonic model for WGB. Our analysis identified hazard zones based on ongoing tectonic processes. The integrated morpho-tectonic risk map shows 34.9% of WGB is low-risk, 22.1% intermediate, and 43.0% high-risk. This research highlights direct links between active tectonics and drainage networks, offering new insights into how tectonic and weathering activities shaped WGB landforms. Notably, hazardous zones are primarily controlled by highly deformed areas, not surface drainage, underscoring neotectonics’ crucial role in WGB’s main drainage systems. The spatial distribution of these zones further supports tectonic activity along east-west and northwest-southeast fault lines on the northern El-Galala El-Bahariya plateau and the eastern strip parallel to the GOS.