河台金矿伽马能谱K异常成因探讨  

The Genesis for Anomalous Values of K from Gamma-Ray Spectrometric Survey in the Hetai Gold Deposit

作　　者：朱江建[1,2] 林舸[2] 曾乔松[2] 龚贵伦[3] 刘彬 张婧[5] 

机构地区：[1]北京矿产地质研究院,北京100012 [2]中国科学院矿物学与成矿学重点实验室广州地球化学研究所,广东广州510640 [3]中国人民武装警察部队黄金第十一支队,湖南宁乡410600 [4]中色地科矿产勘查股份有限公司,北京100012 [5]北京勘察技术工程有限公司,北京100085

出　　处：《地质与勘探》2014年第5期961-970,共10页Geology and Exploration

基　　金：老矿山典型矿床成矿规律总结研究(项目编号:121200113086300);国家自然科学基金项目:广东河台金矿富矿包中金的超常富集机制研究(No.41172082)资助

摘　　要：河台金矿是一个典型的与韧性剪切带有关的金矿床,也是目前粤西、桂东南已发现的最大的金矿床。为了给深边部找矿提供科学依据,本文对河台金矿伽马能谱K异常进行了研究。河台金矿动力变质分异期、热液期与表生期生成的富钾矿物只有绢云母,表明本区引起伽马能谱K高异常的矿物应为绢云母。这些绢云母可能成因于糜棱岩化过程与金-黄铁矿-石英热液蚀变过程中斜长石的绢云母化。其中,糜棱岩化过程引起的K高异常具有异常宽度小的特点,且具有指示糜棱岩带与矿体位置的意义。金-黄铁矿-石英阶段引起的K高异常具有异常宽度大的特点,且主要发育于糜棱带与不同岩性的接触带。伽马能谱K低异常则可能成因于热液成矿期中金-石英-多金属硫化物阶段的热液蚀变作用及低钾花岗伟晶岩脉的侵入。The Hetai gold deposit is the largest gold deposit in Western Guangdong and Southeastern Guangxi,which is related to the ductile shear zone. In order to find scientific basis and references for prospecting,this paper studied the anomalous values of K from Gamma-ray spectrometric survey in the Hetai gold deposit. The K bearing mineral generated in dynamic metamorphic differentiation period,hydrothermal stage and supergene stage in the Hetai gold deposit is only sericite,suggesting that high values of K from Gamma-ray spectrometric survey should be caused by sericite. The increasement of sericite should be caused by sericitization from plagioclase in the process of mylonitization and the alteration of gold-pyrite-quartz bearing hydrothermal fluid. The high value belts of K caused in the process of mylonitization are narrow,and can indicate the location of mylonites and orebodies. The high value belts of K caused by gold-pyrite-quartz bearing hydrothermal fluid are wide,and can indicate the location of mylonites and the contact zones of different rocks. Low values of K may be caused the alteration of gold-quartz-sulfide bearing hydrothermal fluid and invasion of granitic pegmatite.

关 键 词：伽马能谱 河台金矿 糜棱岩 K异常 

分 类 号：P618.51[天文地球—矿床学]