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云南麻栗坡钨矿是近年新发现的超大型白钨矿矿床,成因独特。其主要矿段南温河—洒西一带与钨矿相关的变质地层为猛硐岩群南秧田岩组(Pt1n),原岩主要为碳酸盐类,其中的泥灰岩夹层是形成中生代含矿夕卡岩的围岩;南捞片麻岩、老城坡及团田片麻状花岗岩为钨成矿重要基础。控矿构造解析表明,中生代以来强烈的自SE向NW方向的多层次推覆构造变形造成洒西岩组、老城坡及团田片麻状花岗岩、南秧田岩组和南捞黑云二长片麻岩自上而下的空间叠置关系,导致赋矿围岩产生的剪切裂隙成为中生代晚期岩浆热液运移并交代钙质泥灰岩形成顺层含矿夕卡岩的主要空间。含矿夕卡岩锆石U-Pb年代学及与成矿有关的黑云母Ar-Ar年代学研究成果结合华南中生代构造变形及大规模钨锡成矿时代讨论,表明麻栗坡南温河—洒西一带钨成矿作用与中侏罗世以来由于板块聚合而导致的华南岩石圈持续挤压(170~150 Ma)及其后期伸展减薄(130~80Ma)密切相关,并相应形成早期挤压背景下受推覆构造控制的层控夕卡岩型及后期伸展背景下变粒岩型及长石石英脉型白钨矿床。提出南温河外围广泛分布的老城坡及团田片麻状花岗岩深部,以及洒西矿区深部可以寻找南秧田岩组变质岩及夹于其中的含钨夕卡岩层位的找矿思路,并得到了深部钻孔验证。因此,南温河—洒西一带应该具有寻找层控夕卡岩型钨矿床的巨大潜力。除此之外,研究区NW向南温河断裂(南温河水库所在位置)北部大片片麻状花岗岩深部也应该具有良好的找矿远景。
The Malipo tungsten deposit in Yunnan Province is a newly discovered ultra-large scheelite deposit discovered in recent years due to its unique origin. The metamorphic strata associated with the tungsten deposits in the Nanwanhe-Xixi area, the main ore section, are the southern seedling Tian-Yan Formation (Pt1n) of the Mengdong Group and the protoliths are mainly carbonates. The marl interbed is formed by Mesozoic ore-bearing The surrounding rock of skarn; the Nuliu gneiss, the old city slope and the Tuantian gneissic granite are the important basis of tungsten mineralization. The analysis of the ore-controlling structure shows that the strong deformation of the Nappealt belt from the SE to the NW since the Mesozoic resulted in the formation of the Xaxiyan Formation, the Old City slope and the Tuantian gneissic granite, the Nanyantian rock formation, The top-down spatial superposition of gneisses leads to shear fractures in the ore-bearing rocks as the main space for late magmatic hydrothermal migration and calcareous calcareous metamorphic skarn formation. U-Pb chronology of the ore-bearing skarn and the biotite Ar-Ar geochronology related to metallogenetic research. Based on the discussion of the Mesozoic tectonic deformation and large-scale tungsten-tin mineralization age in South China, it is shown that the Nanwenhe- The tungsten mineralization in Saxi area is closely related to the continuous extrusion of the South China lithosphere (170-150 Ma) and its extension and thinning (130-80 Ma) due to the plate polymerizations since the Middle Jurassic, and the early squeezing Stratigraphic skarn-type and lateritic extensional gravel-type and feldspathic quartz vein type scheelite controlled by nappe structure under pressure background. It is proposed that the deep-lying old city slope and the gneissic gneissic granite in the periphery of the Nanwenhe River and the prospecting for the metamorphic rocks in the Nannyatian Formation and the tungsten-bearing skarn layers in the deep part of the Xixi mining area should be looked for Deep hole verification was obtained. Therefore, the South Wenhe-Xixi area should have great potential for finding stratigraphic-controlled skarn-type tungsten deposits. In addition, deep NW gneissic granites in the north NW of the study area should have a good prospecting potential.