Discussion on the Metallogenic Dynamic Environment and Mineralization for Zhaishang Gold Belt in Gansu Province

Zhaishang gold deposit is a large Carlin and Carlin-like type gold deposit in the western part of the Min-Li basin,west Qinling Mountain.The gold deposit hosted in the Guoyingniuchang anticline and the fracture oblique anticline,the ore bearing strata are middle-upper Devonian and Lower Permain.The south ore belt is mainly controlled by faults,and the ore vein of north belt is mainly controlled by the interlayer shear zone.Mineralized bodies developed along the contact interface of sandstone,sandy slate and carbonaceous slate.We found a small amount of quartz diorite porphyrite veins in the mine,and the veins are closely associated with gold mineralization.The ore-forming fluid has the characteristics of low temperature,low salinity,low density.Mineralization is mainly concentrated in the Late Triassic-Early Jurassic(220~170 Ma),Early Cretaceous(130~100 Ma)and PaleogenePeriod(60Ma),inthe midlate Himalayan period,presumablysuperpositionofthe new tectonic hydrothermal mineralization.Zhaishang gold deposit have three metallogenic conditions,first enrichment of shallow and deep metallogenic material,followed by material migration has the power source strong,again is the change of the physical chemical conditions and ore containing sufficient space is an important guarantee for ore formation.Therefore,the formation of Zhaishang gold deposit is the result of multiphase superposition of many ore-forming factors in the relatively limited favorable metallogenic tectonic realm.