摘要
铁矿是我国的重要战略矿产资源;考虑大型矿床的发现主要源于对小型矿床的研究,本文研究洛大式菱铁矿矿床地质及成矿规律,以促进菱铁矿矿床的找矿发现。基于区域地质、区域重力异常和矿产地质调查数据,阐述矿床地质特征;进而总结成矿规律,展望找矿前景。结果表明:矿床分布于含矿建造与隐伏花岗岩类侵入体的耦合区域,控矿构造样式为羽状右行走滑断层系统,厘定的成岩期、热液期和表生期成矿过程中,热液期有石英—硫化物(Ⅰ)、石英—菱铁矿—白云石(Ⅱ)和石英—白云石—方解石(Ⅲ)三个成矿阶段,菱铁矿仅形成于第Ⅱ阶段。矿床的热液成矿作用特征显著,岩浆热液可能参与成矿,矿石结构构造具有浅成特征。结论认为,洛大式菱铁矿属于浅成中—低温热液型矿床,羽状走滑构造系统决定矿床的深部与外围找矿空间。
The iron ore is one of important strategic resources in our country.Considering the discovery of large size deposits were mainly from study of middle-small size deposits,this paper aims to study of mineral geology and mineralization regularities of Luoda style siderite deposits,so as to promote prospecting for the siderite deposits.On the basis of regional geology,regional gravity,and geological surveying for mineral resources,we expound geological characteristics of the deposits.Furtherly,we give a summary of ore-forming regularities and some ore prospecting predictions of the deposits.The results are as follows:The deposits in all distribute in the area ore-bearing formation coupling with concealed granitoid intrusives,the ore-controlling structure was a system of feathery strike-slip faults,there were three mineralization periods orderly composed of diagenetic period,hydrothermal period,and hypergene period,in which the hydrothermal period was orderly composed of quartz-sulfide stage,quartz-siderite-dolomite stage,and quartz-dolomite-calcite stage,the siderite was only formed in stage II.The deposits are characterized by hydrothermal mineralization,the magma hydrothermal could had participated in the mineralization,and the ore structure is characterized by that of epithermal type deposits.We conclude that the Luoda style siderite deposits belong to epithermal type,and the feathery srike-slip fault system limits the deep and external ore-searching prospective.
作者
何甘地
何进忠
牛鹏飞
朱永新
吴义布
HE Gan-di;HE Jin-zhong;NIU Peng-fei;ZHU Yong-xin;WU Yi-bu(Geological Survey of Gansu Province,Lanzhou 730000,China)
出处
《甘肃地质》
2024年第1期26-34,共9页
Gansu Geology
基金
中国地质调查局地质调查项目“甘肃崖湾—大桥地区金锑矿整装勘查区(巴藏幅)矿产调查与找矿预测”(121201004000-150017-35)
甘肃省自然资源厅科技创新项目(202231)。
