河南桐柏上上河金矿地质特征及综合成矿模型  

Geological characteristics and comprehensive metallogenic model of Shangshanghe gold deposit in Tongbai County of Henan

作　　者：柴银红 许岩炯 陈建立[1] CHAI Yinhong;XU Yanjiong;CHEN Jianli(The First Geological Exploration Institute,Henan Provincial Bureau of Geology and Mineral Exploration and Development,Zhengzhou 450001,Henan,China)

机构地区：[1]河南省地质矿产勘查开发局第一地质勘查院,河南郑州450001

出　　处：《矿产与地质》2022年第6期1136-1143,共8页Mineral Resources and Geology

基　　金：中国地质调查局项目“河南省桐柏县老湾金矿接替资源勘查”(编码:1212011220697)资助。

摘　　要：上上河金矿位于秦岭褶皱系东段,南秦岭褶皱带北缘,老湾金矿带中部。本研究依托接替资源勘查项目上上河矿段外围及深部找矿的最新成果,开展对矿床的综合评价。在总结矿床地质特征的基础上,对控矿地质条件进行了分析,进而探讨了矿床的综合成矿模型。研究成果表明,上上河金矿赋矿层位为中元古界龟山岩组,矿体受NWW—NW向断裂带控制、斜切地层产出,矿石类型以蚀变岩(黄铁绢英岩)型、含黄铁矿石英脉型为主,黄铁矿为金的主要载体矿物;矿床成因类型为矿体形态受断裂控制的中、低温热液蚀变岩型金矿床;其综合成矿模型为:区域变质作用使龟山岩组中Au活化、迁移,在韧性剪切变质变形作用下形成与早期韧性剪切带有关的矿源层;后续构造热运动形成与早期韧性剪切带具有一定继承演化关系的晚期脆性走滑断裂体系;最后燕山期花岗岩浆析出的含矿岩浆热液通过水/岩反应使赋存在早期韧性剪切带的金活化、迁移,进入到成矿流体中,在近地表脆性断裂带内沉淀成矿。研究成果可为该区深部地质找矿提供一定参考。Shangshanghe gold deposit is located in the eastern section of Qinling fold system,the northern margin of South Qinling fold belt,and the middle area of the Laowan gold belt.This study relies on the latest result of the replacement resource exploration project,prospecting in the periphery and deep parts of Shangshanghe mining section.A comprehensive evaluation of the deposit is carried out.On the basis of summary of the geological characteristics of the deposit,the geological ore-controlling condition is analyzed,and the comprehensive metallogenic model of the deposit is discussed.The study result shows that the ore-bearing layer of Shangshanghe gold deposit is Gueshanyan Formation of the Middle Proterozoic Erathem,the ore body is controlled by the NWW-NW striking fault zone and produced by obliquely cutting the strata.The ore types are mainly altered rock(beresitization)type and pyrite-bearing quartz vein type,and pyrite is the main carrier mineral of gold.The genetic type of the deposit is a medium-low temperature hydrothermal altered rock gold deposit controlled by fault.The comprehensive metallogenic model is described as follows.Regional metamorphism causes the activation and migration of Au element in the strata of Guishanyan Formation,and the source layer related to the early ductile shear zone is formed under the action of ductile shear metamorphism and deformation.The late brittle strike-slip fault system is formed by the subsequent tectonic thermal movement,which has a certain inheritance and evolution relationship with the early ductile shear zone.Finally,the gold hosted in the early ductile shear zone is activated and migrated through water/rock reaction by the ore-bearing magmatic hydrothermal solution released from the Yanshanian granite magma.Gold is incorporated into the ore-forming fluid and deposited in the brittle fault zone near surface.The research result can provide some reference for the geological prospecting at the deep place in this area.

关 键 词：上上河金矿 深部找矿 成矿模型 河南桐柏 

分 类 号：P618.51[天文地球—矿床学]