Authors: Eman Ghoneim*, University of North Carolina - Wilmington
Topics: Remote Sensing, Arid Regions, Geomorphology
Keywords: Crater, The Sahara, Remote Sensing, GIS, DEM, Radar Penetration
Session Type: Paper
Start / End Time: 8:00 AM / 9:40 AM
Room: Muses, Sheraton, 8th Floor
This work communicates the discovery of a sandy buried large circular structure in the eastern part of the Great Sahara in North Africa. Remote sensing image fusion and transformation of multispectral and Synthetic Aperture Radar of dual wavelengths (C and L-bands) and multiple polarizations (HH, HV and VV), were adopted in this work. The processed hybrid image enabled the combining of surface spectral properties and subsurface roughness information for better understanding of the structure. Radar long wavelength, in particular, enabled the penetration of desert sands and revealing the buried structure. The structure exhibits a clear outer rim with traces of concentric faults, an annular flat basin and an inner ring surrounding remnants of a highly eroded central peak. SAR hybrid imagery clearly shows the interior wall of the structure is incised with radial pattern gullies that originate at or near the crater periphery, implying a much steeper rim wall in the past. Residing in the Cretaceous Nubian sandstone formation, suggests an old age of ≤ 65 Ma for the structure. The morphology of the eastern side of the structure is largely eroded by a now dry large river course. Confirmation of the impact crater hypothesis requires collection and analyses of rock samples from in and around the structure, a task that is currently challenging due to the environmentally inaccessibility of the area and for security reasons. If proven to be of an impact origin, the Rimal Structure could hold promises for hosting economically valuable ore deposits in the region.