Transition from the Sedimentary Manganese Deposit to Supergene Manganese Ore in Eastern Hebei,North China:Evidences from Mineralogy and Geochemistry  

作　　者：Lingtong Xu Wenchao Yu Song Jin Hua Guo Pengfei Ma Yuansheng Du Cailong Zhang 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources,School of Earth Sciences,China University of Geosciences,Wuhan 430078,China [2]Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock,Ministry of Natural Resources ofPeoplesRepublicof China,Guiyang 550004,China [3]Hebei Institute of Geological Survey,Shijiazhuang 050081,China [4]State Key Laboratory of Biogeology and Environmental Geology,School of Earth Sciences,China University of Geosciences,Wuhan 430078,China [5]Geological Exploration Technology Center of Hebei Bureau of Geology and Mineral Exploration and Development,Shijiazhuang 050081,China

出　　处：《Journal of Earth Science》2025年第1期11-28,共18页地球科学学刊(英文版)

基　　金：supported by the National Key R&D Program of China(No.2022YFF0800200);the NSFC(Nos.U1812402 and 42072131);Most Special Fund(No.MSFGPMR33)from the State Key Laboratory of GPMR;the CUG Scholar Scientific Research Funds(No.2022036);the NSF of Hebei Province(No.D2021334001);Research Project of Talent Engineering Training of Hebei Province(No.B2020005007);Research Project of Postdoctoral Scientific Research Station of HBGMR(No.454-0602-YBN-Z9E4);Natural Science Foundation of Hebei Province(No.D2021334001);the Central Government Guides Local Funds for Scientific and Technological Development(No.236Z7608 G)。

摘　　要：Original sedimentary manganese(Mn)deposits and supergene Mn ores are important Mn resources in China.However,the geochemical information from Chinese supergene Mn ores is scarce,and the relationship between sedimentary Mn deposits and supergene Mn ores is ambiguous.In this study,we collected the original Mn-bearing dolomitic sandstones(ZK20-3 drillcore)and supergene Mn ores(Longmen Section)from eastern Hebei,North China for systematic petrographic,mineralogical and geochemical analyses.Our new data help us to figure out the transformation from original Mn-bearing deposits to supergene ores.The main minerals of original Mn-bearing dolomitic sandstones are quartz and feldspar,with minor muscovite,dolomite,rhodochrosite,ankerite,and kutnohorite.Supergene Mn-oxide ores only emerged in the middle part of the Longmen(LM)Section,and mainly contain quartz,pyrolusite,cryptomelane,todorokite and occasional dolomite.The possible transformation sequence of Mn minerals is:kutnohorite/rhodochrosite→pyrolusite(Ⅰ)→cryptomelane(todorokite)→todorokite(cryptomelane)→pyrolusite(Ⅱ).For Mn-oxide ores,Fe,Na and Si are enriched but Al,Ca,Mg and K are depleted with the enrichment of Mn.For original and supergene ores,the total rare earth element+ytterbium(∑REY)contents range from 105.68×10^(-6)to 250.56×10^(-6)and from 18.08×10^(-6)to 176.60×10^(-6),respectively.Original Mn ores have similar slightly LREE-enriched patterns,but the purer Mn-oxide ore shows a HREE-enriched pattern.In the middle part of the LM Section,positive Ce anomalies in Mn-oxide ores indicate the precipitation of Ce-bearing minerals.It implies the existence of geochemical barriers,which changed p H and Eh values due to the long-time influence of groundwater.

关 键 词：supergene manganese ore GEOCHEMISTRY Gaoyuzhuang Formation North China 

分 类 号：P618.32[天文地球—矿床学]