A Comparative Study of the Mineralization and Unmineralized Breccias Along the Whistle Offset Dyke in the North Range of the Sudbury Impact Structure

THE ISSUE

Breccias, such as Sudbury breccia and metabreccia, are preferred hosts to Cu-Ni-PGE mineralization in footwall country rocks and offset dykes of the Sudbury Igneous Complex. The ability to identify and distinguish unmineralized and mineralized metabreccia along offset dikes would help focus exploration efforts.

THE SOLUTION

The main objective of this research project is to develop criteria for discriminating between unmineralized and mineralized metabreccia. By providing tools that aid in the recognition of mineralized metabreccia, exploration efforts and dollars can be focused on the most favourable host rocks.

THE RESULT

Metabreccia is one of the main hosts of Cu-Ni-PGE mineralization along the Whistle offset dike. Petrographical, modal mineralogical, image analysis, mineral chemistry, and lithogeochemical observations do not suggest any significant differences between mineralized and unmineralized metabreccias.