淮南煤田太原组铝质泥岩元素地球化学特征  

The elemental geochemical characteristics of aluminous argillites in Taiyuan Formation from Huainan coalfield

作　　者：陈冰宇 刘桂建[1] 吴盾[2] 孙若愚 CHEN Bingyu;LIU Guijian;WU Dun;SUN Ruoyu(School of Earth and Space Sciences,Key Laboratory of Crust-Mantle Materials and Environments,University of Science and Technology of China,Chinese Academy of Sciences,Hefei 230026,China;Exploration Research Institute,Anhui Provincial Bureau of Coal Geology,Hefei 230088,China;Institute of Surface-Earth System Science9 Tianjin University,Tianjin 300072,China)

机构地区：[1]中国科学院壳幔物质与环境重点实验室,中国科学技术大学地球和空间科学学院,安徽合肥230026 [2]安徽省煤田地质局勘查研究院,安徽合肥230088 [3]天津大学表层地球系统科学研究院,天津300072

出　　处：《煤田地质与勘探》2018年第3期21-27,共7页Coal Geology & Exploration

基　　金：国家重点基础研究发展计划“973计划”课题(2014CB238903); 国家自然科学基金项目(41672144)

摘　　要：华北聚煤盆地南缘淮南煤田晚石炭世–早二叠世太原组含煤岩系普遍沉积铝质泥岩,然而,对于多层铝质泥岩的形成条件及其地球化学特征尚未开展深入研究。在本次研究中,系统采集了淮南煤田张集煤矿补Y1钻孔岩心样品,采用XRF和ICP-OES、ICP-MS分别测试了主量元素和微量元素,对铝质泥岩地球化学特征及其地质成因进行分析。结果表明:不同层位的铝质泥岩来源于同一源区,铝土质泥岩可能受到了更强烈的红土化作用导致其明显偏离SiO_2/Al_2O_3和Fe_2O_3/Al_2O_3趋势线;Sr/Ba的结果表明铝质泥岩是在不稳定的海陆交互沉积环境下形成的,V/Cr和V/(V+Ni)的结果表明铝质泥岩是在贫氧到厌氧的沉积环境中形成的;综合主量元素和微量元素的结果,表明了不同层位铝质泥岩的母岩可能是附近古陆的中酸性火成岩,母岩风化产物经迁移至淮南地区沉积成岩。Aluminous argillites are widely deposited in the Late Carboniferous to Early Permian Taiyuan Formation of Huainan coalfield at the southeast margin of the North China Plate. However, knowledge about their formation conditions and geochemical characterizations are not presently known. We collected samples from a borehole in Zhangji coal mine and tested their geochemical parameters, including major and trace elements, by XRF and ICP-OES and ICP-MS, respectively. The geochemical characteristics and geological origin of Huainan aluminous argillites were investigated. Results show that： nearly all the argillites have comparable ratios of SiO,2/Al,2O,3 and Fe,2O,3/Al,2O,3, suggesting that they were possibly derived from the same source materials, however, bauxitic argillites significantly deviate from the correlation slopes, indicating that they probably suffered a more extensive laterization than aluminous argillites; the Sr/Ba ratios of the studied argillite samples were possibly deposited in an unstable paleodepositional environment, while the V/Cr and V/（V＋Ni） ratios suggested an anoxic environment; based on the comprehensive consideration of major and trace element results, the studied aluminous argillites probably derived from the common parent rocks composed of felsic to intermediate igneous rocks. These argillites were presumably deposited under anoxic environments in Huainan area.

关 键 词：铝质泥岩 地球化学特征 主量元素 微量元素 晚石炭世–早二叠世太原组 淮南煤田 

分 类 号：P595[天文地球—地球化学]