滇东南麻栗坡南温河—洒西一带钨矿控矿要素及深部找矿突破  

Ore-controlling characteristics of tungsten deposits in the Nanwenhe Saxi area and deep prospecting breakthrough

作　　者：阙朝阳[1,2] 张达[1] 狄永军[1] 毕珉烽[1] 黄孔文 徐建珍[1] 刘艳宾[1] 李晓宗 祖世元 范正哲 王森[1] 

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]紫金矿业集团西南有限公司,云南昆明650214 [3]文山麻栗坡紫金钨业集团,云南文山663600

出　　处：《地学前缘》2014年第2期286-300,共15页Earth Science Frontiers

基　　金：云南省麻栗坡县政府委托项目"云南省麻栗坡县老君山地区钨多金属矿床成因及成矿预测";高等学校学科创新引智计划(111计划)(B07011)

摘　　要：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，表明麻栗坡南温河一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（170～150Ma）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，南温河一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 was found in recent years, which is a super-large scheelite deposit with distinctive genesis in Yunnan Province. The metamorphic strata related to tungsten mineralization in the Nanwenhe-Saxi area is the Mengdong Group, and its protolith is mainly carbonate. The main ore blocks concentrate on Nanwen Rive-Saxi, and the metamorphic strata which has close relationship with tungsten ore blocks is Nayangtian formation of Mengdong Group（Pt~ n）. The main rock type in this metamorphic strata is carbonatite~ the wall rock type is marl rock~ and the Nanlao gneiss, Laochengpo gneissic granite and Tuantian gneissic granite are important foundation rocks for tungsten mineralization. The tectonic ore-controlling analysis result suggests that there were several times of strong muhiphase thrusting-nappe type deformation occurred from SE direction to NW in the Mesozoic. These deformations caused the formation of the layered spatial relationship among Saxi formation, Laochengpo and Tuantian gneissose granite, Nanyangtian formation and Nanlao gneiss. And their vertically overlapping relationship resulted in the shear fractures in the base rock, which provided the space for the migration of magmatic hydrothermal fluids that contained calcareous marl and through hydrothermal metasomatism caused the formation of the bedded skarn-type tungsten ore. The tungsten mineralization in Nanwenhe-Saxi was associated with the lithosphere extrusion（170- 150 Ma） by the convergence of middle Jurassic plates and the post-lithospheric stretching and thinning（130 - 80 Ma） in South China, forming the thrusting stratabonnd skarn during the compressional environment and the greisen and feldspar quartz vein scheelite deposit during the extensional environment. These are accounted for by the zircon U-Pb dating result in the skarn coupled with Ar-Ar dating result on biotite combined with the discussions o{ Mesozoic tectonic deformation and large tungsten tin metallogenic epoch of South China. It is proposed that the N

关 键 词：南温河钨矿床 洒西钨矿床 推覆构造 控矿特征 深部找矿 麻栗坡 

分 类 号：P618.67[天文地球—矿床学]