摘要
钱家店砂岩型铀矿床是松辽盆地发现的特大型铀矿床,目前已发现的铀矿主要赋存在上白垩统姚家组下段,矿体呈板状、透镜状,主要受层间氧化带控制。通过对钱家店砂岩型铀矿层间氧化带各带(氧化带、过渡带及还原带)的主量元素、微量元素、稀土元素进行测试分析,结果表明各带地球化学特征存在较大的差异,其中依据Fe2O3、FeO、Al2O3、SiO2、Na2O及K2O可对层间氧化带进行较准确的分带,MgO、CaO具有一定的分带指示意义。从氧化带到过渡带,趋于富集的微量元素主要为放射性元素(U)、大离子亲石元素(Li、Ba)、亲硫元素(Ni)、高场强元素(Nb、Ta)和性质活跃的变价元素(Mo)等,且LREE、MREE和HREE均有不同程度富集,反映了水-岩作用时间较长、强度较大。有机碳、S全、ωFe^3+/ωFe^2+还原性指标在不同分带的显著差异表明,随着含氧含铀水在姚家组地层中迁移,还原性组分变化强烈,具有明显的分带指示意义。
The Qianjiadian sandstone-type uranium deposits is a large uranium deposits discovered in the Songliao Basin. The uranium deposits discovered mainly occur in the Lower Member of the Upper Cretaceous Yaojia Formation. The ore body is tabular and lenticular,mainly controlled by the interlayer oxidation zone. By testing and analyzing the main elements,trace elements and rare earth elements in the oxidation zone of the Qianjiadian sandstone-type uranium deposits( oxidation zone,transition zone and reduction zone),the results show that the geochemical characteristics of each zone vary greatly,where the interlayer oxidation zone can be zoned relatively accurately by Fe2O3,FeO,Al2O3,SiO2,Na2O and K2O and Mg O and CaO have certain indication significance for zoning. From the oxidation zone to the transition zone,the trace elements that tend to be enriched are mainly radioactive elements( U),large ion lithophile elements( Li,Ba),chalcophile elements( Ni),high field strength elements( Nb,Ta),active variable valence elements( Mo),etc.,and LREE,MREE and HREE have different degrees of enrichment,reflecting the long water-rock interaction with large intensity. The significant difference of reducing indexes of organic carbon,St,and ωFe^3+/ωFe^2+ in different zones indicates that with the migration of oxygen-uranium containing water in the Yaojia Formation,the reducing components change sharply and have obvious significance of zoning indication.
作者
杨松林
Yang Song-Lin(Research Institute of Exploration and Development of Liaohe Oilfield In.,PetroChina,Liaoning Panjin 124010,China)
出处
《古地理学报》
CAS
CSCD
北大核心
2020年第2期321-332,共12页
Journal of Palaeogeography：Chinese Edition
基金
中国石油天然气股份有限公司科学研究与技术开发项目(编号:2019A-4809(GF))资助。
关键词
松辽盆地
钱家店凹陷
砂岩型铀矿床
姚家组
层间氧化带
地球化学特征
Songliao Basin
Qianjiadian sag
sandstone-type uranium deposits
Yaojia Formation
interlayer oxidation zone
geochemical characteristics
