伊犁盆地煤中关键金属的分布赋存特征  

Distribution regularity and occurrence characteristics of critical metalelements in Yili coals

作　　者：刘双双 王文峰 王文龙[2] 陆青锋 邵峰军 王昱龙 LIU Shuangshuang;WANG Wenfeng;WANG Wenlong;LU Qingfeng;SHAO Fengjun;WANG Yulong(College of Geology and Mining Engineering,Xinjiang University,Urumqi 830047,China;School of Source and Earth Science,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]新疆大学地质与矿业工程学院,新疆乌鲁木齐830047 [2]中国矿业大学资源与地球科学学院,江苏徐州221116

出　　处：《煤炭学报》2022年第5期1761-1772,共12页Journal of China Coal Society

基　　金：国家重点研发计划资助项目(2021YFC2902003);国家自然科学基金资助项目(U1903207,U1903207)。

摘　　要：为查明伊犁盆地煤中关键金属的富集情况,通过工业分析、电感耦合等离子体质谱(ICP-MS)、逐级化学提取试验(SCEE)方法及带能谱的扫描电镜(SEM-EDS),结合盆地北部皮里青矿区西山窑组煤与顶底板样品及前人研究成果,探讨煤中关键金属的分布赋存特征。结果表明:伊犁盆地煤中关键金属质量分数整体上并不高,只有局部地区受砂岩型铀矿影响出现了U,Se,Mo及Re等元素的高度富集。在水平上,伊犁盆地的伊宁凹陷呈现南缘显著高于北缘及中部,而北缘又略高于中部的分布特征,这与南缘受到后生富铀溶液渗入、南北缘距离物源更近以及北部的同沉积断裂构造有关。在垂向上,伊犁盆地不同成煤时期的关键金属分布表现为中段的三工河组>下段的八道湾组>上段的西山窑组:受后生富铀溶液渗入,三工河组煤中关键金属质量分数较高;由于构造条件、沉积环境、沼泽地下水位等不同,八道湾组煤中关键金属质量分数高于西山窑组。皮里青矿区西山窑组煤中关键金属富集程度与盆地整体分布情况相符,处于亏损~正常水平,且具有更强的无机亲和性:Li,Zr,Hf,Nb等元素都主要以硅酸盐结合态形式赋存,主要存在于黏土矿物中;Be,V,In,Sr等元素主要以碳酸盐或硫酸盐结合态形式赋存,主要存在于方解石、菱铁矿、石膏中;W主要以硫化物结合态形式赋存,与煤中黄铁矿关系密切;Mo,Se主要以有机结合态形式存在,皮里青矿区煤中不富集U,Se,Mo和Re等元素,主要是由于缺少后生富铀溶液的入渗及不具备富铀海西期花岗岩蚀源区这样的地质条件及可淋溶性条件。To ascertain the enrichment of critical metal elements in the Yili coals,the distribution law and occurrence characteristics of critical metal elements in the Yili coals were analyzed using proximate analysis,inductively coupled plasma mass spectrometry(ICP-MS),sequential chemical extraction experiment(SCEE)and scanning electron microscope with energy spectrum(SEM-EDS),combining with the coal,roof and floor samples of Xishanyao Formation in the Piliqing Mining Area in the north of the basin and some previous research results.The results show that the content of critical metals in the coals of the Yili Basin is not high on the whole,and only partial areas are affected by sandstone-type uranium deposits where U,Se,Mo,Re are enriched.Horizontally,the critical metal elements in the coals of the Yining Depression of the Yili Basin show the distribution characteristics that the southern margin is significantly higher than the northern margin and the middle.Meanwhile,the northern margin is slightly higher than the middle,which is related to the infiltration of the epigenetic uranium-rich solution in the southern margin,the closer distance between the northern and southern margin to the sediment source region,and the synsedimentary fault structure in the north.Vertically,the distribution of critical metal elements in different coal forming periods in the Yili Basin is Sangonghe Formation(in the middle section)>Badaowan Formation(inthe lower section)>Xishanyao Formation(in the upper section).As a result of the infiltration of the epigenetic uranium-rich solution,the content of associated metal elements in the coal of the Sangonghe formation is high.Due to different structural conditions,basement subsidence rate,sedimentary environment,and swamp ground water table,the concentration of associated metal elements in the Badaowan Formation coals are higher than that in the Xishanyao Formation.The enrichment degree of critical metals in the Xishanyao Formation coals of the Piliqing Mining Area is consistent with the overall dis

关 键 词：关键金属 伊犁盆地 侏罗系煤 地球化学 铀矿 

分 类 号：P618.11[天文地球—矿床学]