安徽怀宁地区象山石墨矿床的晶质石墨矿物学特征研究  

Study on the mineralogical characteristics of crystalline graphite from Xiangshan graphite deposit in Huaining County,Anhui Province

作　　者：李小东[1] 李勇[2] LI Xiaodong;LI Yong(Geological Survey of Anhui Province(Anhui Institute of Geological Science),Hefei 230001,Anhui,China;326 Geological Prospecting Party,Bureau of Geology and Mineral Resources Exploration of Anhui Province,Anqing 246003,Anhui,China)

机构地区：[1]安徽省地质调查院(安徽省地质科学研究所),安徽合肥230001 [2]安徽省地质矿产勘查局326地质队,安徽安庆246003

出　　处：《华东地质》2025年第1期68-78,共11页East China Geology

基　　金：安徽省公益性地质工作“宣城地区晶质石墨矿调查评价(编号:2022-g-1-6)”项目资助。

摘　　要：文章运用多种分析测试方法及研究手段,首次对安徽怀宁地区象山石墨矿床开展了晶质石墨矿物学特征研究。象山矿床的晶质石墨具有完整的晶型,呈鳞片状集合体;能谱分析结果显示,晶质石墨中的碳原子含量为91.99%~92.74%;激光拉曼分析结果显示,石墨具有较高的结晶度和有序且完整的碳原子结构,其激光拉曼特征图谱缺失D_(1)峰和D_(2)峰,与石墨烯的激光拉曼图谱具有较高的相似性;粉晶衍射分析结果反映了晶质石墨具有2H型石墨特征,轴长a=0.2461~0.2466 nm,c=0.6693~0.6700 nm,晶胞体积V=0.0351~0.03529 nm^(3)。石墨鳞片厚度为37.1~43.3 nm,石墨化度为82~96,估算其成矿变质温度为542.4~587.2℃,3R多型含量为9.03%~10.37%,δ^(13)C值为-29.223‰~-26.926‰,表明石墨碳质来源于地层中同源沉积的生物有机碳质,更接近泥碳及现代有机质的含量水平,可能不存在岩浆带入的含碳流体及碳酸盐岩分解的无机碳。In this paper,the researchers have employed a variety of analytical testing methods and research techniques to conduct the first study on the crystalline graphite mineralogical characteristics of Xiangshan graphite deposit in Huaining County,Anhui Province.The crystalline graphite of the Xiangshan deposit has a rel-atively complete crystal form and appears as flake aggregates.Energy spectrum analysis shows that the content of C atom in the crystalline graphite ranges from 91.99%to 92.74%.Laser Raman spectroscopy shows that graphite has a high degree of crystallinity and an orderly complete carbon atomic structure.Its laser Raman characteristic spectrum lacks D_(1) and D_(2) peaks,similar to the Raman spectroscopy in graphene.Powder X-ray diffraction(XRD)reveals that the crystalline graphite exhibits characteristics of 2H type graphite,with an axis length a=0.2461~0.2466 nm,c=0.6693~0.6700 nm,and a unit cell volume V=0.0351~0.03529 nm^(3).The thickness of graphite flake varies from 37.1~43.3 nm,the degree of graphitization 82~96,the estimated metamorphic tem-perature 542.4~587.2℃,the content of 3R polymorphism 9.03%~10.37%andδ^(13)C value-29.223‰~-26.926‰.These findings all suggest that the graphite carbon derived from bio-organic carbon deposited in the strata,which is closer to the level of peat and modern organic matter.Besides,there is no evidence of carbon-con-taining fluid brought in by magma and inorganic carbon resulting from carbonate rock decomposition.

关 键 词：安徽怀宁地区 象山石墨矿床 晶质石墨 矿物学特征 

分 类 号：P571[天文地球—矿物学] P575[天文地球—地质学]