(1. 中南大学 有色金属成矿预测教育部重点实验室,长沙 410083;
2. 中南大学 地球科学与信息物理学院,长沙 410083)
摘 要: 通过对丁家山铅锌矿成矿时代、成矿物质来源、成矿流体通道、储矿场等成矿系统要素的全面分析,明确了丁家山铅锌矿区成矿作用为燕山期花岗质岩浆与经加里东期区域变质的新元古界马面山群龙北溪组上段富钙质岩之间的接触交代变质作用。Pb和S等同位素研究及化探扫面结果显示:矿区成矿物质由燕山期花岗岩和马面山群龙北溪组地层共同提供,H和O同位素研究证实:成矿流体由大气降水和岩浆水共同组成;精细化矿物场填图指示成矿流体主要通过北东向断层运移,而矿区储矿场由马面山群龙北溪组上段、上侏罗统长林组和其间的角度不整合接触界面构成。丁家山铅锌矿属挤压构造成矿系统(大类)下属的与燕山期花岗质岩浆有关的接触交代成矿系统类。
关键字: 成矿系统;成矿作用;接触交代变质;丁家山铅锌矿
Dingjiashan Pb-Zn ore district in Meixian, Fujian Province
(1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Central South University,
Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China)
Abstract:Based on the systematic study of metallogenic system elements, such as metallogenic epoch, ore-forming materials source, pass way of ore-forming fluid and site of ore body, it is found that the metallogenesis of Dingjiashan Pb-Zn ore district is contact metasomatic metamorphism between Yanshanian granite and the regional metamorphism calcareous rock of Neoproterozoic Mamianshan Formation Longbeixi group upper. The research on isotope of Pb, S and geochemical exploration confirms that the ore-forming materials are supplied by Yanshanian granite and Mamianshan Formation Longbeixi group, and the research on isotope of H and O confirms that the ore-forming fluid is composed of magmatic water and atmospheric water. The mineral mapping indicates that the ore-forming fluid flows along NE fault. There are three sites of ore body, Neoproterozoic Mamianshan Formation Longbeixi group upper, Jurassic Changlin group and angular unconformity between them. Dingjiashan Pb-Zn ore district is contact metasomatic metamorphism metallogenic system related to Yanshanian granite, which belongs to compression structure metallogenic system.
Key words: metallogenic system; metallogenesis; contact metasomatic metamorphism; Dingjiashan Pb-Zn ore district