新疆阿吾拉勒成矿带塔尔塔格铁矿床的地质特征、形成时代及其找矿意义  

Geological characteristics and mineralization age of Taertage iron deposit in Awulale Metallogenic Belt,Xinjiang,and its significance for prospecting

作　　者：张永乐 欧阳荷根[1] 蒋宗胜[1] 孙强 杨燕 ZHANG YongLe;OUYANG HeGen;JIANG ZongSheng;SUN Qiang;YANG Yan(MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Henan Nonferrous Mineral Exploration Co.,Ltd.,Zhengzhou 451460,Henan,China;Henan Nonferrous Mineral Exploration and Development Investment Co.,Ltd.,Zhengzhou 451460,Henan,China)

机构地区：[1]中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室,北京100037 [2]河南有色矿产勘查有限公司,河南郑州451460 [3]河南有色矿业勘查开发投资有限公司,河南郑州451460

出　　处：《矿床地质》2025年第2期502-518,共17页Mineral Deposits

基　　金：中国地质调查局地质调查项目(编号:DD20221684、12120115036601);中央级科研院所基本科研业务费项目(编号:KK2203)联合资助。

摘　　要：新疆阿吾拉勒成矿带中的铁矿主要产于石炭系火山-沉积岩建造中。文章报道了该带一种新的铁矿类型,即以安山玢岩为赋矿围岩的铁矿——塔尔塔格铁矿。塔尔塔格铁矿的磁铁矿化以浸染型、空洞充填型和脉型3种形式赋存在安山玢岩中,其中,浸染型铁矿化及其伴生的面型钾化蚀变,与典型斑岩型铜矿成矿岩体中发育的矿化蚀变特征颇为相似,指示塔尔塔格矿床可能是一例与安山玢岩有关的玢岩型铁矿。笔者对塔尔塔格矿床成矿期的热液金云母进行^(40)Ar/^(39)Ar同位素测年,获得的坪年龄为(315.7±3.0)Ma,这一年龄与阿吾拉勒成矿带中热液脉型磁铁矿和沉积-变质型赤铁矿的形成时间基本一致,印证了它们之间存在成因联系。基于此,笔者提出:①阿吾拉勒成矿带中的玢岩型、热液脉型和沉积-变质型铁矿,或可视为一巨型海相安山质富铁岩浆-热液活动在不同的地质控矿条件下,形成具内在联系的铁成矿系统的不同端员;②阿吾拉勒成矿带已知热液脉型铁矿的深边部,可能存在一个浅成至超浅成安山玢岩体及相关的玢岩型铁矿化,应在后期找矿过程中加以重视。Previous studies show that iron deposits in the Awulale Metallogenic Belt,Xinjiang,are mostly hosted in Carboniferous volcanic-sedimentary rocks.In this study,we report a new type of iron deposit-the Taertage iron deposit,which is hosted in an andesitic porphyrite intrusion.Iron mineralization in the andesitic porphyrite can be divided into three types of disseminated,cavity-filling and hydrothermal vein.The disseminated iron mineralization and related pervasive potassium alteration are similar to the alteration observed in the causative intrusions of typical porphyry copper deposits,indicating that the Taertage iron deposit is most likely an andesitic porphyriterelated iron deposit.^(40)Ar/^(39)Ar dating of ore-related hydrothermal phlogopite yields a plateau age of(315.7±3.0)Ma at Taertage,which is consistent with the ore-forming age of hydrothermal-vein and sedimentary-metamorphic iron deposits in the Awulale Metallogenic Belt.We thus propose that:①the andesitic porphyrite-,hydrothermal vein and sedimentary-metamorphic type iron deposits in the Awulale Metallogenic Belt are genetically related and probably belongs to a single iron metallogenic system;②There may exist a shallow to ultra-shallow(andesitic)porphyrite body and related porphyrite-type iron mineralization deep or periphery of the existing hydrothermal vein-type iron ore in the Awulale Metallogenic Belt,which should not be ignored in the later prospecting process.

关 键 词：玢岩型铁矿 ^(40)Ar/^(39)Ar测年 塔尔塔格铁矿 阿吾拉勒成矿带 

分 类 号：P618.31[天文地球—矿床学]