广西湖润锰矿矿层软沉积变形特征  

Soft-sediment deformation characteristics in the Hurun Manganese Mining area,Guangxi,South China

作　　者：杨凯 张启连 谢振朝 宫研 陈胜 覃瑞才 韦松良 曹淑芳 区洪威 YANG Kai;ZHANG Qilian;XIE Zhenchao;GONG Yan;CHEN Sheng;QIN Ruicai;WEI Songliang;CAO Shufang;OU Hongwei(Guangxi Geological Survey Institute,Nanning 530023,China)

机构地区：[1]广西壮族自治区地质调查院,广西南宁530023

出　　处：《沉积与特提斯地质》2023年第1期101-116,共16页Sedimentary Geology and Tethyan Geology

基　　金：“广西关键矿产资源深部勘查人才小高地(桂组通字[2019]85号,2019—2023)”项目;广西找矿突破战略行动地质矿产勘查项目“广西靖西县湖润矿区朴隆矿段外围碳酸锰矿普查(桂国土资函[2016]397号、桂自然资函[2019]758号)”的成果。

摘　　要：锰矿作为我国大宗紧缺矿产,其矿体特征被学者广泛研究。然而关于矿层软沉积变形特征的研究却不多,其特征和成因有待厘清。湖润锰矿处于广西下雷超大型锰矿床的外围,作者通过对其主矿层Ⅱ+Ⅲ矿层的观察研究,发现Ⅱ+Ⅲ矿层以液化变形为主的软沉积变形发育,如液化砂、液化泥(亮)晶脉、自碎屑角砾、液化底劈、微褶皱纹理、同沉积断裂等,局部地段可见完整的变形序列,同时矿层被上覆岩系超覆;此类变形不仅在横向上有延伸,在垂向上还有重复且跨度长,从晚泥盆世至石炭纪均有发育,符合软沉积变形地震成因的典型特征。加之稀土元素地球化学特征显示成矿期热水参与了成矿作用,表明锰矿形成时期沉积盆地伸展作用强烈,矿化发生于裂陷槽下斜坡带。对比国内外著名的大型超大型锰矿床,认为软沉积变形应与成矿密切相关,可作为重要的找矿标志。China is shortage of manganese mineral resources.Although manganese orebodies have been widely studied by scholars,characteristics and genesis of soft-sediment deformation in manganese ore layers are unclear.Hurun manganese ore is located in the periphery of the super-large Xialei manganese deposit in Guangxi.A number of liquefied deformation structures,such as liquefied sandstone,liquefied micritic(sparry) vein,autoclast breccia,liquefied diaper,micro-corrugated lamination,and synsedimentary microfractures,occurred as soft-sediment deformation in the Ⅱ+Ⅲ ore layers,and the complete deformation sequences can be seen in some areas,while the ore layers were overlapped by later strata.This kind of structure not only extends horizontally,but also repeats vertically with a long span,developing from Late Devonian to Carboniferous,which is consistent with the typical soft-sediment deformation structures related to seismic genesis.In addition,the geochemical characteristics of REE show that the hot water participated in the mineralization during the ore-forming period,indicating a strong extension of sedimentary basin during the mineralization of manganese deposits in a lower slope zone of the aulacogen.Comparing with famous large or super-large manganese deposits at home and abroad,it is considered that the soft-sediment deformation is closely related to the mineralization of manganese deposits and it can be used as an important indicator for ore prospecting.

关 键 词：湖润锰矿 软沉积变形 地震成因 伸展作用 找矿标志 

分 类 号：P618.32[天文地球—矿床学]