Structural controls and the role of fault dynamics during the formation of vein-hosted gold deposits in the Bendigo-Ballarat Zone of the Lachlan Fold Belt

The timing of mineralisation, the nature of associated hydrothermal alteration, and the isotopic and chemical compositions of the fluids point to ore genesis involving large volumes of C-O-H metamorphic fluids whose flow has been channelised along high permeability fault zones. The development of auriferous vein systems has been controlled by the coincident development of structural and geochemical traps. Cyclic fluctuations in fluid pressure and shear stress accompanying episodes of fault motion are shown to control repeated episodes of fracture opening, fluid mixing, and mineralisation. -from Authors