摘要
基于开鲁盆地钱家店铀矿床姚下段砂岩的碎屑组分分析、重矿物组合特征以及稀土元素分析,探讨了该砂岩型铀矿的物质来源及矿质来源。碎屑组分分析指示该地区姚下段砂岩碎屑矿物以石英为主,碱性长石次之,岩屑类型丰富且含量较高;重矿物组合特征反映出姚下段重矿物以稳定矿物钛磁铁矿、白钛石、锆石和石榴石等为主,不稳定矿物绿帘石、硬绿泥石及黑云母含量较少;稀土元素特征显示出蚀源区花岗岩与过渡带相似的REE分布模式,花岗岩的ΣREE值与过渡带的ΣREE值较接近,且均具有铕负异常。综上所述,钱家店地区姚家组下段沉积显示了多物源体系的特征,碎屑矿物以中酸性岩浆岩来源为主,变质岩来源碎屑为辅;物源主要有3大方向:西北部舍伯吐凸起物源、东部架玛吐凸起物源及南部的燕山造山带物源,物源总体以南部燕山造山带为主,同时受多方向物源的共同控制。燕山晚期中酸性富铀岩浆岩在钱家店铀矿床铀源供给方面扮演了重要的角色。
Based on the clastic component analysis,heavy mineral assemblage characteristics and rare earth element analysis of the lower part of Yaojia Formation sandstone in Qianjiadian uranium deposit from Kailu Basin,the material and mineral sources of the sandstone-type uranium ore are discussed.The analysis of clastic composition indicates that the clastic minerals of the lower part of Yaojia Formation sandstone in this area are mainly quartz,followed by alkaline feldspar.The characteristics of heavy mineral assemblage indicate that the heavy minerals in the lower part of Yaojia Formation are mainly the stable titanomagnetite,white titanite,zircon and garnet,while the unstable minerals such as chlorite,hard chlorite and biotite contain less.Rare earth element characteristics show erosion source area granite and transition zone of similar REE distribution patterns,graniteΣREE value and the transition zone ofΣREE value is close to,and have europium negative anomaly.In conclusion,the lower member of Yaojia Formation in Qianjiadian area shows the characteristics of multi-provenance system.Clastic minerals are mainly from intermediate-acid magmatic rocks and supplemented by metamorphic rocks.There are three main sources:the source of the Shebotu uplift in the northwest,the source of the Jiamatu uplift in the east,and the source of the Yanshan orogen in the south.The Late Yanshanian acid uranium-rich magmatic rocks play an important role in the uranium source supply of Qianjiadian uranium deposit.
作者
单芝波
Shan Zhibo(Liaohe Oilfield Exploration and Development Research Institute,Panjin,Liaoning 124010)
出处
《地质科学》
CAS
CSCD
北大核心
2020年第4期1248-1265,共18页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
中国石油天然气集团公司科学研究与技术开发项目(编号:2019A-4809(GF))资助。
关键词
钱家店铀矿床
物源分析
铀源
重矿物
稀土元素
Qianjiadian uranium deposit
Provenance analysis
Uranium source
Heavy mineral
REE
