The western sub-province of the Paleozoic Lachlan Orogen in Victoria is dominated by thick turbidite sequences overlying Cambrian basement volcanics. The region was subjected to multiple Cambrian to Late Devonian regional deformation events, followed by extensive post-tectonic granitic magmatism. The western Lachlan Orogen is considered a typical orogenic gold province and hosts a large number of goldfields, including the world-class Bendigo-Ballarat goldfields. A variety of geochronological methods (e. g. U-Pb zircon; Re-Os sulfide; Ar-40/Ar-39 whole-rock, mica) have been used to constrain the timing of gold mineralisation, and the relationship to metamorphism/deformation/magmatism. Regional granitic magmatism is relatively well constrained from U-Pb zircon dating, with the timing of deformation/metamorphism and gold mineralisation reliant largely on Ar-40/Ar-39 dating results. Owing to inconsistencies in the available Ar-40/Ar-39 data and recent revisions to Ar-40/Ar-39 monitor ages and decay constants, we recalculate and re-evaluate all existing Ar-40/Ar-39 age results.
Phillips, D., Fu, B., Wilson, C., Kendrick, M., Fairmaid, A., & Miller, J. (2012). Timing of gold mineralisation in the western Lachlan Orogen, SE Australia: A critical overview. Australian Journal of Earth Sciences, 4, 495 - 525. https://doi.org/10.1080/08120099.2012.682738