Geo-Environmental Hazard Assessment of Archaeological Sites and Archaeological Domes-Fatimid Tombs-Aswan, Egypt

The Fatimid state was established in Egypt in 969 and lasted until the end of the dynasty in 1171. During the Fatimid rule in Egypt, a large set of monuments were erected. A significant portion of these monuments were shrines dedicated to the descendants of the Prophet Muhammed, especially in Aswan. Groundwater rising, at present, has introduced severe deterioration to the ancient earthen mud-brick architecture of the Fatimid tombs in Aswan city (Egypt). However, monitoring the influence of anthropogenic and environmental aspects on the deterioration issues in Fatimid tombs has not yet been considered. To this end, the scope of this pilot study is to investigate the structural stability and weathering vulnerability of the building materials of mud-brick structures in the Fatimid Cemetery before restoration labor. This was achieved using an integration of remote sensing (Landsat 8 and SRTM-DEM) and hydrogeological datasets in the Geographic Information System (GIS), along with a physicochemical and mineralogical analysis of various materials (the bearing soil, wall plasters, and Muqarnas) from the affected cemeteries. The morphological and mineralogical compositions of the collected samples were analytically examined by using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) and CT scan. Moreover, geotechnical studies were conducted for the perched soil water and subsoil, including the analysis of the physiochemical composition and heavy metals using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results of multitemporal analysis of land use/land cover (LULC) changes displayed the growth and appearance of wetlands near the Fatimid tombs area over the last decades, boosting the geo-environmental risks from soil water rising. Furthermore, the detailed analytical investigations of building materials and soil foundations showed that this unique and substantial ancient Islamic archaeological site of Egypt shows weak geotechnical properties, and it is highly sensitive to natural and anthropogenic stressors. This innovative methodology can produce novel recommendations and results to the Ministry of Antiquities in Egypt and the Heritage Commission in Saudi Arabia for the adequate restoration of monuments.