Geological Characteristics and Regularity of Gold Enrichment of North Ore-Controlling Ductile Shear Zone in Huachanggou Gold Deposit

The regional ductile shear zone is well developed in the Huachanggou gold deposit,and it has gone through multiple activities from right-handed earlier to left-handed later and then right-handed latest.The North ore-controlling ductile-brittle shear zone,which is the production of the evolution of the regional ductile zone,is located at the bottom of Tiejiashu-Miaowan thick-bedded limestone.The North gold ore zone,with a length of more than 1 km and a thickness about 70 cm,is controlled by North ore-controlling ductile shear zone,and nip-out tendency is not found from the surface to(1 120) m level.Pyrite is the most important metallic mineral in it.Natural gold,which includes phaneric gold and micro-gold,is the major gold mineral.And the micro-gold can be further divided into industion gold,interystal porositional gold and fissure gold.The complex ore structure and the sample structural style indicate the tectonic features of hydrothermal deposit.The formation of ore zone can be divided into hydrothermal stage and supergene stage.Most of the phaneritic gold in protogenous ore,and the inclusion gold and fracture gold in micro-gold ore are closely related to pyrite.It is clear that pyrite has experienced ductile-brittle deformation,and therefore it is the best carrier mineral of gold.Because of multiple activities of North ductile-brittle shear zone,the gold ore bodies are enriched.It is predicted that the ore zone may be discovered below the(1 120) m level.