湘西南黔阳盆地“大塘坡式”锰矿成因分析:以湖南靖州地区为例  

Genetic analysis of "Datangpo type" manganese deposit in Qianyang Basin,southwest Hunan: A case study of Jingzhou, Hunan Province

作　　者：王佳 李凤杰[2,3] 张玺华 陈聪 高兆龙 WANG Jia;LI Fengjie;ZHANG Xihua;CHEN Cong;GAO Zhaolong(College of Earth Science,Chengdu University of Technology,Chengdu 610059,Sichuan,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,Sichuan,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,Sichuan,China;Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu 610041,Sichuan,China)

机构地区：[1]成都理工大学地球科学学院,四川成都610059 [2]油气藏地质及开发国家重点实验室(成都理工大学),四川成都610059 [3]成都理工大学沉积地质研究院,四川成都610059 [4]中国石油西南油气田公司勘探开发研究院,四川成都610041

出　　处：《中国地质》2023年第1期249-263,共15页Geology in China

基　　金：中国地质调查局项目(DD20160032)资助。

摘　　要：【研究目的】锰矿作为一种金属矿产,应用于国民经济的多个领域。黔阳成锰盆地是中国重要的锰矿基地,其锰矿床类型为赋存于南华系大塘坡组地层中的一套海相碳酸锰矿床,资源储量大,开采历史长,但其成矿模式尚不清楚。【研究方法】本文以锰矿集中分布的湖南靖州地区为例,在野外剖面实测、地球化学数据分析的基础上,通过Co/Zn-(Cu+CO+Ni)图解、Fe-Mn-(Cu+CO+Ni)×10三端元判别图解、(Zr+Ce+Y)×100-(Cu+Ni)×15-(Fe+Mn)/4三角图解以及Al/(Fe+Mn+Al)比值、(Fe+Mn)/Ti比值和Fe/Ti比值等一系列判别指标分析了锰矿中锰元素的来源。利用锰矿石的V/Cr、Th/U、Ce/La以及Ce标志分析了锰矿石沉积时的古环境。【研究结果】黔阳成锰盆地靖州地区锰矿石中锰元素主要来源于海底热液系统,沉积时水体处于贫氧—缺氧环境,前期形成的断裂带为锰元素的运移提供了通道。【结论】黔阳成锰盆地靖州地区锰矿石是冰期由地壳深部经众多断裂带上升到海盆中的锰元素,在间冰期与海水中的CO_(3)^(2-)相结合富集而成。[Objective] As a kind of metal mineral, manganese ore is used in many fields of national economy. Qianyang manganese-forming basin is an important manganese ore base in China. Th type of manganese deposit is a set of marine manganese carbonate deposits occurring in the strata of Datangpo Formation of Nanhua System, with large resource reserves and long mining history,but its metallogenic model is still unclear. [Methods] This paper takes Jingzhou area of Hunan Province as an example, where manganese deposits are concentrated. On the basis of field profile measurement and geochemical data analysis, the sources of manganese in manganese ores are analyzed by Co/Zn-(Cu+CO+Ni) diagram, Fe-Mn-(Cu+CO+Ni)×10 three-terminal discriminant diagram,(Zr + Ce + Y) × 100-(Cu + Ni) × 15-(Fe + Mn)/4 ternary diagram, Al/(Fe + Mn + Al) ratio,(Fe + Mn)/Ti ratio and Fe/Ti ratio. The paleoenvironment of manganese ore deposition was analyzed by using V/Cr, Th/U, Ce/La and Ce markers of manganese ore. [Results] The manganese element in the manganese ore in Jingzhou area of Qianyang manganese basin mainly comes from the seafloor hydrothermal system, and the water body is in the oxygen-poor-anoxic environment at the time of deposition. The fault zone formed in the early stage provided a channel for manganese migration. [Conclusions] The manganese ore in Jingzhou area of Qianyang manganese basin is formed by the enrichment of the combination between manganese and CO_(3)^(2-) in interglacial period,and the manganese in the sea basin were from the deep crust through fault zones in the glacial period.

关 键 词：沉积型锰矿 成锰盆地 菱锰矿 成矿模式 沉积环境 矿产勘查工程 湖南 

分 类 号：P618.32[天文地球—矿床学]