MAPPING THE WESTERN PART OF THE BOU AZZER INILIER: ASTER MULTISPECTRAL IMAGE PROCESSING

Abstract

The Bou Azzer mining district, located in the Anti-Atlas Mountains of Morocco, is worldrenowned for its serpentinized Neoproterozoic ophiolitic complex. These complex host large deposits of CoNi-Fe arsenides and sulf-arsenides, containing significant quantities of cobalt, nickel, gold and copper. Bou Azzer's unique cobalt mineralization makes it an important player on the world market. Unlike other regions, where cobalt is often a by-product of the mining of other metallic substances, Bou Azzer's deposits primarily mine cobalt as the main ore. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is an instrument aboard the Terra platform of the Earth Observation System (EOS), used to measure solar radiation reflected and emitted by the Earth's surface in different spectral bands. ASTER measures radiation in 14 spectral bands, including three VNIR (visible and near infrared) bands and six SWIR (mid-infrared) bands, as well as five TIR (thermal infrared) bands. This study presents a mapping methodology using ASTER imagery, with the aim of demonstrating the effectiveness of remote sensing in guiding mineral exploration efforts. The focus is on mapping contact zones in serpentinite, which play a central role as metallotect influencing cobalt mineralization in this geological formation. In addition, this approach is a practical way of reducing mining exploration costs. The results obtained were validated using the 1/50 000 scale geological map of Bou Azzer, supplemented by field visits.