In Zhangbaling Tectonic Belt,two types of mineralization,auriferous quartz veins and alter- ation halos,can observed within many deposits.The pressure of metallogenesis of auriferous al- teration halos ismuch higher t...In Zhangbaling Tectonic Belt,two types of mineralization,auriferous quartz veins and alter- ation halos,can observed within many deposits.The pressure of metallogenesis of auriferous al- teration halos ismuch higher than thatof quartz vein,thetemperatures ofmetallogeneses ofthese two types of orebodies are don’tthe same Geochemistry study indicates thatboth ofthem are mi- cro- mesothermal deposits related to Yanshanian granites.The results of proton microprobe analy- sis of sulphides from the gold deposits in the area show that the“invisible” gold existed in sul- phides is in the form ofmicro inclusions,and the concentration of“invisible” gold in sulphidemin- erals within quartz vein is poorerthan thatfrom alteration halos.Field observation shows thatthe structural modality of the fractures controlling the orebodies of auriferous quartz vein is different from thatof the auriferous alteration zones.The fracture controlling the orebodies of auriferous alteration halos is compress- shearfracture,auriferous quartzvein is controlled by extensive fault. The alteration halos crosscut by auriferous quartz vein.The wallrocks of the former altered strongly and developed alteration zones well.The wallrocks of auriferous quartz vein altered slightly.The results of tectonogeochemical study shows that the concentration of associated met- allogenesis elements and intensity of alteration are positively correlated with tectonic deformation strength for auriferous alteration halos.Itindicates that it is probably a general character for mi- cro- mesothermal gold deposits due to the multistages of metallogeneses took place.The tectonic environmentis the most important fact determining the mechanism of fluid flow and precipitationof gold,and then the types of mineralization and modes of gold.展开更多
文摘In Zhangbaling Tectonic Belt,two types of mineralization,auriferous quartz veins and alter- ation halos,can observed within many deposits.The pressure of metallogenesis of auriferous al- teration halos ismuch higher than thatof quartz vein,thetemperatures ofmetallogeneses ofthese two types of orebodies are don’tthe same Geochemistry study indicates thatboth ofthem are mi- cro- mesothermal deposits related to Yanshanian granites.The results of proton microprobe analy- sis of sulphides from the gold deposits in the area show that the“invisible” gold existed in sul- phides is in the form ofmicro inclusions,and the concentration of“invisible” gold in sulphidemin- erals within quartz vein is poorerthan thatfrom alteration halos.Field observation shows thatthe structural modality of the fractures controlling the orebodies of auriferous quartz vein is different from thatof the auriferous alteration zones.The fracture controlling the orebodies of auriferous alteration halos is compress- shearfracture,auriferous quartzvein is controlled by extensive fault. The alteration halos crosscut by auriferous quartz vein.The wallrocks of the former altered strongly and developed alteration zones well.The wallrocks of auriferous quartz vein altered slightly.The results of tectonogeochemical study shows that the concentration of associated met- allogenesis elements and intensity of alteration are positively correlated with tectonic deformation strength for auriferous alteration halos.Itindicates that it is probably a general character for mi- cro- mesothermal gold deposits due to the multistages of metallogeneses took place.The tectonic environmentis the most important fact determining the mechanism of fluid flow and precipitationof gold,and then the types of mineralization and modes of gold.
