Examining the controls on gold deposit distribution in the Swayze greenstone belt, Ontario, Canada, using multi-scale methods of spatial data analysis

Abstract

Understanding the spatial controls on mineral deposits is crucial in mineral exploration targeting. This paper uses a combination of spatial data analysis techniques, such as the distance distribution method, Fry, nearest neighbor index, Ripley’s K-function multi-distance, fractal, and kernel density analysis, to better define controls on the distribution of gold deposits in the Swayze greenstone belt, Ontario, Canada. According to results obtained with the distance distribution method, D2 structures were critical in controlling the spatial distribution of the gold mineralization, with 97% of the gold deposits occurring within 7 km of these structures (and 65% within 4 km). Fry analysis confirmed this spatial relationship with a close agreement between the orientations of the D2 structures and gold deposit alignment. The outcome of Ripley’s K-function cluster analysis suggests that gold deposits occur within 4 km distances of other gold deposits. These findings are consistent with the results from the fractal analysis, showing that gold deposit distribution is bifractal and that different geological features occurred at local (<8 km) versus regional (>8 km) scales. We conclude that higher-order D2 structures and lower-order faults connected to the D2 structures acted as pathways to focus gold-bearing hydrothermal fluids, thus leading to the observed concentration and distribution of gold deposits at the regional to local scales.