Geostatistical Study of Airborne Geophysical Data of the Tiouit Mining Area (Eastern Anti-Atlas, Morocco)

The present work focuses on the Tiouit mining zone that is part of the Moroccan Eastern Anti-Atlas. The study area is characterized by its strategic mining aspect considering the mining showings related to its geological, structural, and geodynamic factors. The mining site of Tiouit is very well known by the gold mine currently in shutdown. The genetic models proposed by different authors agree on an epithermal origin of copper porphyry type. This type of deposit is characterized by a strong radioactive activity related to the circulation of hydrothermal fluids materialized by enrichment in potassium and depletion in Thorium, a low magnetic susceptibility due to oxides a low apparent resistivity to the presence of conductive minerals.

The main objective of the present work is to use principal component analysis (PCA) on the various airborne geophysical data, including gamma-ray spectrometry (concentrations of radioactive elements ⁴⁰K and ²³²Th), magnetism (magnetization contrast due to magnetic susceptibility), and electromagnetism (apparent electrical resistivity) to describe the physicochemical behavior of the mining zones in operation as well as to prospect other zones favorable for exploration.

The geostatistical study of these data highlights the adequate principal component (PC) to visualize these geophysical variables. We chose PC4 to visualize the zones favorable for mining concentration because it describes the same physical and chemical characteristics represented by the Tiouit alteration zone. The collection and X-ray fluorescence analysis of 32 samples in the field yielded high grades of Arsenic (84 g/t), Copper (5.87%), Iron (19%), Lead (5.7%), and Zinc (7%).