تاثير دگرشكلي بر رفتار طلا در نهشته ماسيوسولفيد سرشار از طلاي باريكا، شرق سردشت

Deformation effects on the gold bihavior in Barika gold-rich massive sulfide deposit, east of Sardasht

Barika gold mineralization occurred in a Cretaceous metavolcano-sedimentary sequence at northwestern Sanandaj-Sirjan zone. Gold-rich volcanogenic massive sulfide mineralization occurred in a rhyolite to rhyolitic tuff unit which is completely in Barika shear zone. Based on electron microprobe studies, gold is observed to form electrum mostly, and in lattice of other minerals, such as pyrite, galena, tetrahedrite- tenantite, bournonite- boulangerite, twinte- vinnite. The main effect of deformation on the gold mineralization is migration of submicroscopic gold to cracks and crystal defects in minerals to form electrum under low to moderate strain and release of electrum from fractured mineral under higher strain. This behavior of gold can increase recovery of gold in Au-bearing ore deposits (Huston etal., 1992).