Mineralogical Mapping Using Remote Sensing and Geophysical Data in IMITER Anti-Atlas of Morocco

IMITER is an area in Morocco which is considered to be the most important zone for silver exploration. It is characterized by two units: an upper Neoproterozoic volcaniclastic unit and a basal sedimentary unit alternating with Neoproterozoic pelite and sandstone levels, which carry silver mineralization. Remote sensing is the science of obtaining information about an area by analyzing data, such as satellite images, collected by a device or sensor without direct contact with the object studied. Several techniques are used on the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite image: image transformation techniques, such as band ratios, principal component analysis, and unsupervised classification, which are used to successfully identify hydrothermal alteration zones in the area of study. These techniques have been used to contrast the different lithologies and areas of high concentrations of mineral assemblages resulting from alteration of kaolinite, carbonate, oxide iron, Fe 3+ , and ferrous silicate. A comparison between the results obtained and the high-resolution aeromagnetic geophysical data showed the presence of these alterations in the area. The results indicate several areas with high mineralization potential in the study area that can be considered for future systematic exploration programs. The current study showed that ASTER image processing and remote sensing techniques are valuable mapping tools for recognizing hydrothermal alteration areas by providing accurate preliminary maps and cost-effectiveness.