3D geological modelling of the northern Swayze area of the Abitibi greenstone belt: assisting mineral exploration by mapping controls on gold (Au) deposits

Abstract

A 3D geological model of the northern Swayze area is constructed through the integration of lithological, structural, geological cross-sections, and seismic information in a Leapfrog Geo® modelling software to delineate structural geometry and geological distribution of rock units in the area. Using a mineral system approach, important geological features are extracted from the 3D geological model. A log-linear 3D weights of evidence method is used to quantify the spatial association between orogenic gold (Au) mineralization and various geological features that might represent ore-controlling factors. This method reveals that the dominant controls on Au mineralization are the second and third generation of deformation zones (D2 and D3), lithological contacts, and second and third-order faults. The posterior probability model is effective in capturing most of the Au occurrences (81%) within 18% of the study area, and the predictive rate curve indicates that the model performs better than random, as it is effective in predicting 71% of the validation points within 30% of the study area.