投稿时间：2013-07-31
修订日期：2013-11-06
网络发布日期：2013-12-29
中文摘要:位处华北板块北缘东段的辽吉裂谷带内发育有多处中、小型铅锌矿床，其中，同时发育层状和脉状铅锌矿的青城子矿床是典型的代表。为了探讨青城子层状铅锌矿和脉状铅锌矿矿质来源及成因的异同及其所代表的地质意义，利用ICP-MS对层状铅锌矿及其围岩、脉状铅锌矿及其围岩和后期穿矿脉岩进行了稀土元素测试。结果表明，所有样品均具有轻稀土元素（LREE）富集和明显分异的特点。层状铅锌矿及其围岩具有Eu正异常和较弱的Ce负异常，表明其成矿物质均来自上升的深部热水流体与海水的混合热液，在高温、还原流体和海水的参与下成矿。脉状铅锌矿及其围岩稀土元素配分模式与层状铅锌矿及其围岩相似，但其Eu为负异常和Ce异常不明显，部分样品出现较弱的Ce正异常，对比分析穿矿脉岩明显的Eu负异常和Ce正异常以及二者稀土元素总量稍大于层状铅锌矿的特点，文章认为青城子层状矿石为沉积成矿，成矿热液为深部热水流体与海水的混合热液，但后期受到岩浆侵入叠加改造的影响而在局部形成脉状铅锌矿体，引起了Eu负异常和局部Ce正异常的出现以及稀土元素总量的增加。
Abstract:The Qingchengzi ore field lies in Liao-Ji rift valley within eastern block of the North China Craton. The Zhenzigou Pb-Zn deposit is a main deposit among the medium and small sized Pb-Zn deposits in this area. In order to study the origin of the ore material, the corresponding surroundings and the geological significance of the stratiform and veined Pb-Zn ore deposit, the authors analyzed REE of the stratiform Pb-Zn ore and its host rocks, the veined Pb-Zn ore and its host rocks and the veined rocks which penetrate the veined ore body in the Qingchengzi Pb-Zn deposit by using ICP-MS technology. The results show that all samples are characterized by LREE enrichment and differentiation. The REE content of stratiform Pb-Zn ore and its host rocks shows positive Eu and weak negative Ce anomalies in the chondrite-normalized REE patterns of the ores, indicating that the ore-forming hydrothermal fluids were mixed with deep hydrothermal fluids and seawater, which had high temperature and were relatively reductive. Veined Pb-Zn ores are similar to stratiform Pb-Zn ores in chondrite-normalized REE patterns, suggesting that these two ore types had the same ore-forming material sources and surroundings. However, the REE content of most veined Pb-Zn ores shows weaker Eu and Ce anomalies than that of stratiform Pb-Zn ores, with only a few samples showing weak Ce positive anomalies in the chondrite-normalized REE patterns. The veined rocks show apparent Eu positive and Ce negative anomalies in the chondrite-normalized REE patterns, which may explain the differences between these two types of Pb-Zn ores. Besides, the total REE amount of the veined rocks and veined Pb-Zn ores is somewhat larger than that of stratiform Pb-Zn ores. The above REE characteristics indicate that stratiform and veined Pb-Zn ores had the same ore-forming materials and surroundings, whereas the veined Pb-Zn ores and their host rocks were subjected to the magmatic intrusion and superimposed reformation which resulted in the formation of Eu positive anomalies and partial weak Ce negative anomalies as well as the increase of total REE amount.
文章编号：
中图分类号：P618.42;P618.43
文献标志码：
基金项目:本文得到国家自然科学基金青年基金项目（编号：41202042）、中央级公益性科研院所基本科研业务费专项资金资助项目（编号：K1211）和地质矿产调查评价专项项目（编号：12120113091300，1212011085530）的联合资助
引用文本：
马玉波,杜晓慧,张增杰,邢树文,邹跃飞,李斌,杨秀清,王岩.2013.青城子层状/脉状铅锌矿床稀土元素地球化学特征及地质意义[J].矿床地质,32(6):1236~1248MA YuBo,DU XiaoHui,ZHANG ZengJie,XING ShuWen,ZOU YueFei,LI Bin,YANG XiuQing,WANG Yan.2013.REE geochemical characteristics of Qingchengzi stratiform/veined Pb-Zn ore district[J].Mineral Deposits32(6):1236~1248
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