摘要
千鹅冲钼矿是在以往铅锌矿、铜矿找矿的基础上,近期在大别山北麓发现的特大隐伏斑岩型钼矿床。矿体赋存于泥盆系南湾组中,主要受隐伏岩体和构造控制;控矿岩体以富硅、富碱、过铝型以及钾含量高于钠为特征,岩体与围岩接触变质作用不发育。矿床成矿方式以充填作用为主,辉钼矿化主要呈浸染状、细脉状、网脉状产出,有经济意义的矿化有3个阶段。常见的围岩蚀变有硅化、钾长石化、黄铁矿化、绢云母化、绿帘石化、绿泥石化、方解石化、磁铁矿化等。选取了主成矿阶段的4件石英细脉型辉钼矿矿石样品进行了Re-Os同位素定年,获得等时线年龄为(128.7±7.3)Ma,模式年龄加权平均为(127.82±0.87)Ma,这一年龄与穿插于钼矿体中的花岗斑岩脉年龄〔(128.8±2.6)Ma〕很接近,可以界定千鹅冲钼矿床形成时间为早白垩世。
The Qianechong Mo deposit located in Guangshan County of Henan Province is a superlarge concealed porphyry Mo deposit newly discovered at the northern foot of the Dabie Mountain on the basis of previous prospecting for Pb-Zn and Cu deposits.Ore bodies occur in Devonian Nanwan Formation and are controlled by concealed intrusive bodies and structures.The ore-controlling rock is characterized by rich silica and abundant alkali with high K/Na ratios and aluminum content,and contact metamorphism is not well developed between the rock body and the wall rock.Filling mineralization is dominant in the ore deposit.The main molybdenitized minera-lizations include disseminations,veinlets and stockworks,and mineralizations of economical significance can be divided into three stages.The usual alteration types of wall rocks comprise silicification,potassic alteration,pyritization,sericitization,epidotization,chloritization,calcilization and magnetitization.Four veinlet types of quartz Mo-bearing rock samples of the main oreforming period were selected for Re-Os isotope dating,which yielded the isochron age of（128.7±7.3） Ma and the weighted average model age of（127.82±0.87） Ma,which are consistent with the age（128.8±2.6） Ma of the granitic porphyry dike in the Mo deposit,suggesting that the ore deposit was formed in Early Cretaceous.
出处
《矿床地质》
CAS
CSCD
北大核心
2011年第3期457-468,共12页
Mineral Deposits
基金
河南九州丰源资源有限公司"河南省光山县千鹅冲铜(钼)矿地质详查"项目资助
关键词
地质学
隐伏斑岩型钼矿
成矿方式
控矿因素
RE-OS同位素年龄
千鹅冲
河南
geology
concealed porphyry Mo deposit
ore-forming style
ore-controlling factors
Re-Os isotope age
Qianechong
Henan Province
