F3: Oral Presentation C Thursday, 2:30 – 3:00 pm C Gooseberry Falls Room

Lode Gold Deposit Mineral Potential Mapping in Northern Minnesota: GIS Spatial Analysis of Analog Canadian Mining Camps and Integration into Minnesota

Dean M. Peterson
Natural Resources Research Institute
Economic Geology Group
5013 Miller Trunk Highway
Duluth, MN  55811

Lode-gold deposits are one of the world’s principal sources of gold. The most important occurrence of these deposits is in the Archean-age (> 2.5 billion years old) Canadian Shield of Ontario and Quebec, where approximately 200 million ounces of gold has been produced. Similar rock units of the Canadian Shield occur in northern Minnesota, though no significant gold deposits have been discovered in the state. As a general rule, lode-gold mineralization is related to fault systems, and is essentially the last geologic process to occur in formation of the stable continents during the Archean. Therefore, geologic maps depict the last remnants of Archean deformation, and the geometric features depicted on geologic maps are essentially the same as they were during gold mineralization. GIS spatial analysis of the three largest lode-gold mining districts in the Canadian Shield, which includes the Porcupine, Kirkland Lake, and Hemlo districts; and their ~120 million ounces of production, has shed light on some fundamental geological controls on the location of lode-gold deposits. These fundamental features have been spatially analyzed on a 5880 km2 area of northern Minnesota using fuzzy logic combination techniques, into a lode-gold mineral potential map of the area.