【摘要】 东昆仑成矿带沟里金矿区阿斯哈金矿床中的黄铁矿主要分为两类：早期自形结晶黄铁矿和晚期胶状黄铁矿。为了厘清阿斯哈金矿胶状黄铁矿成因及其成矿意义，本文对具有特殊意义的胶状黄铁矿开展原位微量元素分析、面扫分析和原位硫同位素分析。结果表明：胶状黄铁矿富As、Au、Pb和Cu，贫Co和Ni,Co/Ni比值大于10,δ³⁴S值范围变化较窄（+6.1‰～+6.8‰）。结合显微结构，认为胶状黄铁矿为岩浆热液成因，与阿斯哈金矿区内隐伏花岗闪长斑岩体可能存在密切成因联系。迅速沉淀于温度骤降条件下的胶状黄铁矿中的As和Au发生了解耦，微米级粒径黄铁矿为控制固溶体金富集的主导因素。更多还原

【Abstract】 The Asiha vein-type gold deposit,located in the Eastern Kunlun orogenic belt,provides an excellent opportunity for deciphering precipitations of metals and origins of orogenic intrusion-related gold systems.Predecessors have proposed that Asiha gold deposit is an orogenic gold deposit or magmatic hydrothermal gold deposit related to intrusion body,and the genesis of the deposit is controversial. Gold precipitation is closely related to arsenic content and vulcanization,and the main precipitation mechanism is not clear.However,pyrite often occurs in many types of gold deposits,which can provide detailed mineralization information in explaining the source of ore-forming materials,the composition of ore-forming fluids and metallogenic physicochemical conditions,while colloidal pyrite with special structure can provide more important mineralization information. Pyrite is an excellent research object for constraining the genesis of ore deposits.There are two types of pyrite in Asiha gold deposit,namely,early euhedral crystalline pyrite and late colloidal pyrite.Through the study of the chemical composition and microstructure of colloidal pyrite,it is found that gold arsenic decoupling occurs in Asha gold deposit,and the gold precipitation is closely related to the particle size of pyrite. In order to clarify the genesis and gold precipitations of Asiha gold deposit,backscatter electron scanning microscope analysis,in-situ trace element analysis,area scan analysis and in-situ sulfur isotope analysis are carried out for colloidal pyrite. Colloidal pyrite is a parallel or irregular concentric ring belt with irregular complex surfaces. The transition between ribbons is a gradual transition. The bands on the strip often have the contraction pattern of the gel,and the width of the strip is 3～200 μm. Under high-power scanning electron microscope(SEM),it shows the aggregation of micron fine particles and dark gray substrate.Colloidal pyrite is rich in As(median of 3 164×10-6),Au(median of 4.15×10-6),Cu(median of 13 070×10-6),Pb(median of 1 157×10-6),Ag(median of 781.2×10-6),Sb(median of 1 668×10-6),but poor Co in(median of44.48×10-6),Ni(median of 2.96×10-6)and Te(below the detection limit),and the Co/Ni ratio is greater than10. The area scan shows clear zoning characteristics of As,Au,Co,Cu,Mo,Ag and Bi,and the distribution consistency of gold and arsenic is weak. The δ34S value range of colloidal pyrite(+6.1‰～ +6.8‰)is narrow.Combined with the in-situ trace elements,in-situ sulfur isotopes and microstructure of colloidal pyrite,it is considered that the colloidal pyrite is of magmatic hydrothermal origin,which may be a close genetic relationship with the concealed granite porphyry in the Asiha gold deposit. Arsenic and Au in colloidal pyrite precipitated rapidly under the condition of sudden temperature drop are decoupled,and the micron size pyrite is the dominant factor controlling the enrichment of solid solution gold.更多还原