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在阿尔丹 -斯坦洛沃依地盾的西伯利亚地台西南部地区划分出四个金矿带 :(1 ) Ket-Kep带 (主要由矽卡岩型、石英脉和网脉型、碳酸岩中的伊利石 -褐铁矿型以及伊利石 -绢云母交代型矿床或矿点构成 ) ;(2 ) Ulkan带 (伊利石 -云母交代型和石英脉型 ) ;(3 ) Dzhugdzhur带 (石英脉型和矽卡岩型 ) ;(4 ) Dzhugdyr带 (石英 -硫化物脉型 )。含矿矽卡岩成矿时代为中生代 ,而与石英和石英 -硫化物脉型有关的矿化形成于晚元古代、古生代和中生代。大多数中生代的金矿化都与岩浆作用有关。含金岩石的流体包裹体研究结果表明 ,高温成矿过程主要发生在 Dzhugdzhur带的矽卡岩 (5 0 0～ 71 5℃ )和 Ket-Kep带的热液交代型岩石 (5 1 0～ 5 3 0℃ )中 ,这些岩石的矿物流体包裹体中的水溶液盐度高达 40 % Na Cl当量 ,其子矿物主要为 Na,K,Ca的氯化物 ,并以存在 CO2 为特征。Ket-Kep带内高温 (高达 465℃ )和中温条件形成的石英脉和网脉中的流体包裹体盐度达 3 2 % Na Cl当量 ,包裹体中有时含低密度的 CO2 。 Dzhugdzhur带中的含金石英脉形成于 2 2 5～ 2 3 0℃ ,为低盐度成矿溶液 (1 %～ 2 % Na Cl当量 )。 Dzhugdyr带中含金石英 -硫化物脉的成矿温度为 2 60～ 3 90℃ ,成矿溶液为低盐度(1 .5 %～ 7.5 % Na Cl当量 ) KCl水?
Four gold zones are identified on the southwestern part of the Siberian platform of the Altdan-Stalovoye Shield: (1) the Ket-Kep belt (mainly composed of skarn type, quartz vein and reticulate type, carbonatite Illite-limonite and illite-sericite metasedimentary deposits or ore points); (2) Ulkan zone (illite-mica metasomatic and quartz vein); (3) Dzhugdzhur zone (quartz vein type And skarn type); (4) Dzhugdyr band (quartz-sulfide type). Ore-forming skarn mineralization age Mesozoic, and with quartz and quartz-sulfide pulse-type mineralization formed in the late Proterozoic, Paleozoic and Mesozoic. Most Mesozoic gold mineralization is related to magmatism. The results of fluid inclusions in gold-bearing rocks show that the high-temperature mineralization occurred mainly in skarn (550 ~ 71 5 ℃) in the Dzhugdzhur zone and hydrothermal metasomatism in the Ket-Kep zone (510 ~ 5 3 0 ° C), the salinity of aqueous solutions in mineral fluid inclusions of these rocks is as high as 40% Na Cl eq and their sub minerals are mainly Na, K, Ca chlorides, characterized by the presence of CO2. The fluid inclusions in the quartz veins and reticular veins formed in the Ket-Kep zone at high temperatures (up to 465 ° C) and at moderate temperatures have salinities of 32% Na Cl eq and sometimes low density CO2 in the inclusions. The gold-bearing quartz vein in the Dzhugdzhur zone is formed at a temperature of 225-230 ° C and is a low-salinity ore forming solution (1% -2% NaCl equivalent). The gold-bearing quartz-sulphide vein in the Dzhugdyr zone has a mineralization temperature of 2 60-390 ° C and a low salinity (1.5-5.5% Na Cl eq) KCl water in the ore-forming solution.