Maximum Likelihood (MLH) supervised classification of atmospherically corrected Landsat 8 imagery was applied successfully for delineating main geologic units with a good accuracy (about 90%) according to reliable ground truth areas, which reflected the ability of remote sensing data in mapping poorly-accessed and remote regions such as playa (Sabkha) environs, subdued topography and sand dunes. Ground gamma-ray spectrometric survey was to delineate radioactive anomalies within Quaternary sediments at Wadi Diit. The mean absorbed dose rate (D), annual effective dose equivalent (AEDE) and external hazard index (Hex) were found to be within the average worldwide ranges. Therefore, Wadi Diit environment is said to be radiological hazard safe except at the black-sand lens whose absorbed dose rate of 100.77 nGy/h exceeds the world average. So, the inhabitants will receive a relatively high radioactive dose generated mainly by monazite and zircon minerals from black-sand lens.

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A major number of mineral deposits are related to hydrothermal processes. Therefore, the mapping of the hydrothermally alteration areas, connected with mineralization, is crucial in the search for metal deposits. To achieve this purpose, areas of hydrothermal alterations are targeted by processing the airborne gamma-ray spectrometric data to detect areas enriched in potassium that may indicate the existence of potassic alteration zones, which are often associated with hydrothermal alterations accompanied by mineral deposits. Data processing and analysis were performed using the K/eTh ratio, deviation of ideal potassium (Kd) and F-parameter. Besides, determining the environmental radiation risk due to the fact that the study area contains many excavation sites for various mining materials and quarries. Hydrothermal alteration indicator maps show five known mineralizations of gold, copper, molybdenum, fluorite and wolframite, which are associated with hydrothermal processes that took place in the study area. It is possible to note the intimate correlation of mineral deposits present in areas with high potassium content. Positive correlation between the computed hydrothermal alteration indicators (K/eTh, Kd and F-parameter), shown on the ternary image map, revealed favorable high and intermediate targets for the detection of various mineral deposits in the study area. On the other hand, the estimated mean values of absorbed dose rate for all rock units were within the permissible range (28–120 nGy h−1), and the mean annual effective dose rate was below the permissible limit of 1.0 mSv y−1 for these rocks.