鄂东北孙冲锰矿床矿物学特征及其对矿床成因的指示  

Mineralogical characteristics of the Sunchong manganese deposit in the northeast of Hubei Province and its indications for metallogenic genesis

作　　者：陈松 代吉祥 陈松林 刘兴平 蒋之飞 邹院兵 杨振[2] 刘锐[2] CHEN Song;DAI Jixiang;CHEN Songlin;LIU Xingping;JIANG Zhifei;ZOU Yuanbing;YANG Zhen;LIU Rui(Sixth Geological team of Hubei Geological Bureau,Xiaogan 432000,Hubei,China;School of Earth Resources,China University of Geosciences,Wuhan 430074,Hubei,China;Geological Exploration Found Management Center of Hubei Province,Wuhan 430074,Hubei,China)

机构地区：[1]湖北省地质局第六地质大队,湖北孝感432000 [2]中国地质大学(武汉),湖北武汉430074 [3]湖北省地质勘查基金管理中心,湖北武汉430074

出　　处：《矿产勘查》2022年第2期182-191,共10页Mineral Exploration

基　　金：国家自然科学基金项目(41002025);中央高校基本科研业务费专项资金(CUGL140406);湖北省国土资源厅省地质勘查基金项目“湖北省广水市鹰咀山矿区锰矿普查”(HBT-16170054-170534)联合资助。

摘　　要：鄂东北地区是我国典型的新元古代锰成矿域,孙冲锰矿床位于鄂东北东部的蕲春地区。目前对该矿床的矿物学特征还不清楚。本文在详细的矿床地质特征调查基础上,运用电子探针分析(EMPA)方法对该锰矿床进行了详细的矿物学研究,并基于此探讨了其矿床成因。研究结果表明,矿石类型主要为氧化锰矿石和碳酸锰矿石,其中前者锰矿物组成以软锰矿、硬锰矿、黑锰矿及褐锰矿为主,后者所含锰矿物则主要为菱锰矿、锰方解石、锰白云石、黑锰矿及褐锰矿等。矿石结构主要有自形—半自形粒状结构、包含结构、交代残余结构和共结边结构等;矿石构造主要有块状构造和条带状构造等。矿物世代关系表明,锰成矿过程分为三个成矿期,第一期为沉积成岩成矿期,主要形成菱锰矿、锰方解石及锰白云石等原生沉积锰矿物;第二期为变质改造期,主要形成重结晶菱锰矿、黑锰矿、褐锰矿及锰铝榴石等锰矿物;第三期为表生氧化期,主要形成硬锰矿、软锰矿及锰钡矿等锰矿物,造成了锰的进一步富集。结合上述锰矿物学特征及区域研究资料,认为孙冲锰矿床属于典型的沉积变质型锰矿床。Northeast Hubei Province is a typical neoproterozoic manganese metallogenic region in China, Sunchong manganese deposit is located in Qichun County in the east of the area. At present, the mineralogical characteristics of this deposit are not clear. Based on the detailed geological characteristics of the deposit, the mineralogy of the manganese deposit was studied in detail by using EMPA method, and the genesis of the deposit was discussed. The results show that the ore types are mainly manganese oxide ore and manganese carbonate ore, in which the former is mainly composed of pyrolusite, psilomelane, hausmannite and braunite, while the latter is mainly composed of rhodochrosite, manganese calcite, kutnohorite, hausmannite and braunite. The ore structure mainly includes idiomorphic and semiidiomorphic granular structure, poikilitic texture, metasomatic residual structure and co-edgeing structure, and the ore structure mainly includes block structure and banded structure. The manganese mineralization process can be divided into three stages. The first stage is the sedimentary diagenetic mineralization stage, which mainly produces manganese minerals such as rhodochrosite, manganese calcite and kutnahorite. In the second stage of metamorphism and modification, recrystallized rhodochrosite, hausmannite, braunite and spessartite are mainly formed. The third stage is the supergene oxidation stage, mainly forming manganese minerals such as pyrolusite, psilomelane and hollandite. Combined with the above manganese mineralogical characteristics and regional research data, it is considered that Sunchong manganese deposit belongs to a typical sedimentary metamorphic manganese deposit.

关 键 词：矿物学 电子探针 矿床成因 锰矿床 孙冲 鄂东北 

分 类 号：P571[天文地球—矿物学] P611[天文地球—地质学]