摘要
万家坪锰矿位于江南古陆南缘,湘中印支褶皱带东北端,属"大塘坡"式海相沉积变质改造型锰矿床。矿床虽被发现多年,但边深部找矿尚未取得较好的成果。通过对矿区以往勘查资料的整理及野外地质调查,结合采样分析测试,从地层岩性、岩相古地理、氧化—还原条件及热液活动等方面入手,对矿区矿床地质特征、地球化学特征和控矿因素进行了深入分析和总结。研究表明:①锰矿床的形成与海相碎屑沉积密切相关,Fe、Mn在成矿过程中分离非常彻底,在成矿过程中有大量热水注入;②矿床形成时为弱氧化—氧化的沉积环境,Mn^2+与CO2^3-并非直接结合沉淀形成菱锰矿,而是先以锰的氧化物或氢氧化物沉淀后,在后期缺氧且富含有机质的成岩改造过程中逐渐转化形成;③矿区具有较好的成矿地质条件,通过类比邻近的湘潭锰矿,并结合矿区最新勘查成果,预测矿区深部有较好的找矿潜力,值得进一步开展深部找矿工作。
Wanjiaping Manganese Deposit is located in the southern margin of the Jiangnan paleocontinent and in the northeastern end of the Indosinian fold belt in the central of Hunan.It is a typical"Datangpo"manganese deposit.Although the deposit has been discovered for many years,good results have not been achieved in the prospecting of the deep edge.Based on the field geological survey and the previous exploration data of the mining area,combined with sampling analysis,geological characteristics,geochemical characteristics and ore-controlling factors of the deposit are comprehensively analyzed and summarized from the aspects of strata lithology,lithofacies palaeogeography,oxidation-reduction conditions and hydrothermal activity.The study shows that:①The formation of manganese deposit is closely related to marine clastic sedimentation,Fe and Mn are separated thoroughly during the mineralization process,and the hot water is injected during the mineralization process;②The deposit was formed in a weak oxidation-oxidation sedimentary environment,Mn^2+and CO3^2-are not directly combined with precipitation to form rhodochrosite,but first precipitated with manganese oxide or hydroxide,and then gradually transformed into rhodochrosite in the process of anaerobic and organic-rich diagenesis;③By analogy with Xiangtan Manganese Deposit,it is considered that the mining area has good metallogenic geological conditions,combining with the latest exploration results of the mining area,it is predicted that the deep prospecting area has good prospecting potential,and it is worthy to further carry out deep prospecting work.
作者
刘大勇
彭桥梁
苏特
Liu Dayong;Peng Qiaoliang;Su Te(No.418 Geological Party,Hunan Bureau of Geology and Mineral Resources Development,Loudi 417000,China)
出处
《金属矿山》
CAS
北大核心
2020年第8期119-128,共10页
Metal Mine
基金
全国矿产资源潜力评价项目(编号:1212011121015)
湖南省自然资源厅两权价款项目(编号:201303065)。
关键词
深部找矿
锰矿
地质特征
地球化学特征
找矿远景
Deep prospecting
Manganese deposit
Geological characteristics
Geochemical characteristics
Prospecting prospect
