Exploration and deposit models for gold deposits in amphibolite/granulite facies terranes

Summary

Deposit geochemistry and fluid chemistry show that gold deposits in amphibolite/granulite facies terranes are high-temperature analogues of mesothermal deposits.

The metamorphic grade during mineralisation influenced the structural style, host rocks and siting of deposits.

Three classes of deposit are distinguished on the basis of alteration mineralogy in mafic and ultramafic host rocks: the amphibole class, the diopside class, and the diopside-K-feldspar class.

These classes reflect increasing temperatures of metamorphism and mineralisation.

Keywords: amphibolite-granulite facies, gold mineralisation, structure, alteration