A newly-developed multi-algorithm integration technique for mapping the potentially mineralized alteration zones

Abstract

The present work introduces a newly-developed mathematical-based Multi-Algorithm Integration (MAI) technique, GIS weighted overlay model, and field investigations for delineating the potentially mineralized alteration zones. The introduced technique was tested on Semna area in Egypt as a case study. Three different algorithms were utilized to map the abundance of six alteration indicator minerals. The introduced MAI technique enabled combining the outputs of the utilized mapping algorithms allowing the delineation of only the localities that were successfully mapped as the potential for alteration zones occurrence by all the three algorithms together. Localities delineated by only one or even two techniques are not included in the output of the MAI technique, giving rise to a higher accuracy than that of individual techniques. The structural linear features were automatically depicted from a hill-shade image generated from a high-accuracy Digital Elevation Model (DEM). A Geographic Information System (GIS) Weighted Overlay Model (WOM) was then implemented to integrate the alteration maps resulting from the MAI technique with the density map of lineaments. A final hydrothermal-related mineralization potentiality map was obtained and validated through fieldwork and spectral analyses for confirming the occurrence of alteration indicator minerals. Samples were collected from the delineated potentially mineralized localities. The spectral signatures of the collected samples were measured, and spectral analyses were performed to reveal the identity of the existing alteration minerals. Various index alteration minerals were recorded in the measured samples including; kaolinite, montmorillonite, sericite, chlorite, carbonates (dolomite), and iron oxides/hydroxide minerals.