内蒙古苏尼特左旗乌日尼图钨钼矿床同位素地球化学特征  

Isotope Geochemistry of the Wurinitu W-Mo Deposit in Sunid Zuoqi,Inner Mongolia,China

作　　者：杨增海[1] 王建平[1,2] 刘家军[1] 王守光[3] 王清义 康书光 张捷先[1] 赵云[1] 

机构地区：[1]地质过程与矿产资源国家重点实验室,中国地质大学地球科学与资源学院,北京100083 [2]桂林理工大学广西隐伏金属矿产勘查重点实验室,广西桂林541004 [3]内蒙古自治区地质调查院,内蒙古呼和浩特010020 [4]内蒙古自治区第九地质矿产勘查开发院,内蒙古锡林浩特026000

出　　处：《现代地质》2013年第1期13-23,共11页Geoscience

基　　金：国家重点基础研究发展计划项目(2012CB416600);国家自然科学基金面上项目(41272106);中国地质调查局矿产资源调查评价专项工作项目(1212011220923;1212011085471);广西隐伏金属矿产勘查重点实验室开放课题(11-031-20-K6)

摘　　要：乌日尼图钨钼矿位于内蒙古苏尼特左旗境内,是近几年在该区新发现较大规模的钨钼矿床。钨钼矿体主要产于燕山期花岗岩体的内外接触带附近,以细脉状矿化类型为主。同位素测试结果表明:δ34SV-CDT值范围为0.6‰～4.1‰,组成较为稳定;显示钨钼矿体的形成与岩浆作用密切相关,硫可能主要来自岩浆源。矿石样品208Pb/204Pb值范围为38.115～38.353,207Pb/204Pb值范围为15.528～15.591,206Pb/204Pb值范围为18.375～18.528;铅构造模式图解和其参数综合分析表明成矿与岩浆作用密切相关,成矿物质来源于上地壳与地幔的混合,具有壳幔混合特点。热液方解石δ13CPDB=-8.63‰～-6.41‰,δ18OSMOW=-1.49‰～8.72‰,表明热液矿物方解石是2个阶段成矿作用的产物,早期成矿流体碳主要来源于岩浆;成矿作用后期有大气降水的加入。The Wurinitu W-Mo deposit, located in Sunid Zuoqi, Inner Mongolia, is a large scaled W-Mo deposit which is discovered in recent years. The W-Mo orebodies mainly occurred in Yanshanian granite rock body and the nearby contact zone, with the major type of veinlet mineralization. The measured δ^34SV-CDT value of the Wurinitu orebody （0. 6‰ to 4. 1‰） varies in a very limited range and suggests that the formation of W- Mo ore-body is closely related to magmatism and the sulfur may be leached from the granite intrusion. Based on tectonic patterns of lead isotope and related parameters, the lead isotopic compositions of the Wurinitu orebody （^208pb/^204Pb =38. 115 -38. 353,^207pb/^204Pb = 15. 528 - 15.591,^206Pb/^204Pb = 18. 375 - 18. 528） indicate thatthe mineralization may be induced by the magmatism, and ore-forming material is characterized by the source of lower crust and show crust-mantle mixing. δ^13CPDB and δ^18OSMOW of the hydrothermal calcite are from -8. 63‰ to - 6. 41‰ and from - 1.49‰ to 8.72‰, respectively. It shows that the hydrothermal calcite forms in two miner- alization stages. The CO2 in the earlier stage is related to the characteristics of mixture fluids of meteoric water with the magma; and the later hydrothermal ore fluids show magmatic water as the meteoric water added.

关 键 词：乌日尼图钨钼矿床 成矿物质 硫 铅同位素 碳 氧同位素 内蒙古苏尼特左旗 

分 类 号：P618.6[天文地球—矿床学]