河南桐柏围山城金银成矿带成矿物质来源:铅同位素证据  

The Sources of Ore-forming Materials in Weishancheng Au-Ag Mineralization Belt in Tongbai,Henan Province:Lead Isotope Evidences

作　　者：李红梅[1] 魏俊浩[1] 王洪黎 肖广玲[1] 彭丽娜[1] 王发艳[3] 

机构地区：[1]中国地质大学资源学院,武汉430074 [2]河南省第一地质勘查院,南阳473056 [3]湖北省国土测绘院,武汉430010

出　　处：《地质与勘探》2009年第4期374-384,共11页Geology and Exploration

摘　　要：围山城金银成矿带出露有破山银矿床、银洞坡金矿床和银洞岭银矿床等三个大型金银矿床,均受地层和构造的双重控制,赋矿地层为新元古界歪头山岩组,河前庄背斜是成矿带的主要控矿构造。围岩地层歪头山岩组的铅同位素组成具有整体富Th亏U、低μ高ω的特征,与围山城金银成矿带的矿石铅整体富Th亏U、低μ高ω的特征一致。经过年龄校正后,把成矿带内的围岩地层和岩体的全岩铅同位素样品与矿石铅同位素对比分析发现,围岩歪头山岩组与矿石关系最为接近,其次为燕山期梁湾花岗岩体。成矿带的矿石铅具有混源特征。可以认为围岩歪头山岩组和梁湾花岗岩体共同为成矿带提供了铅源及成矿物质。There is Poshan large Ag deposit , Yindongpo large Au deposit , and Yindongling large Ag deposit in Weishaneheng Au-Ag mineralization belt, which are controlled by the strata and structures. Ore bodies hosted in Neoproterozoic Waitoushan Formation, and Heqianzhuang Anticline is main structure to control ore bodies. Lead isotopic compositions of Waitoushan Formation are characterized by rich Th poor U and high ω lower μ, which is consistent with ores lead isotopic compositions. Analyzed lead isotopic compositions of ores, corrected hosted rocks and corrected magmatic rocks in Weishancheng Au-Ag mineralization belt, it is obvious that Waitoushan Formation is the closest to ores, and the Liangwan granitoid is closer to ores too. Ores lead in Weishancheng Au-Ag mineralization belt is mixed of two or more lead reservoirs. It is suggested that lead and Ore-forming materials are derived from Waitoushan Formation and Liangwang granitoid.

关 键 词：铅同位素 成矿物质来源 围山城桐柏 

分 类 号：P618.42[天文地球—矿床学]