松辽盆地钱家店地区姚家组砂岩黏土矿物特征及其与铀矿化的关系  

Features of clay minerals in the Upper Cretaceous Yaojia Formation sandstones of the Qianjiadian Area in the Songliao Basin and its relation to uranium mineralization

作　　者：单芝波 雷安贵[1] 宋柏荣[1] 奥琮 杨松林[1] 韩洪斗[1] SHAN Zhibo;LEI Angui;SONG Bairong;AO Cong;YANG Songlin;HAN Hongdou(Liaohe Oilfield Exploration and Development Research Institute,Panjin 124010,Liaoning,China;Tianjin Center,China Geological Survey,Tianjin 300170,China)

机构地区：[1]辽河油田勘探开发研究院,辽宁盘锦124010 [2]中国地质调查局天津地质调查中心,天津300170

出　　处：《中国地质》2022年第1期271-283,共13页Geology in China

基　　金：中国石油天然气集团公司科学研究与技术开发项目(2019A-4809(GF))资助。

摘　　要：【研究目的】钱家店铀矿床位于松辽盆地西南部,含铀岩系为上白垩统姚家组。目的层中含有大量的黏土矿物,因此揭示姚家组砂岩黏土矿物特征,对铀的成矿作用探讨至关重要。【研究方法】本文通过系统的显微镜下鉴定、扫描电镜、X射线衍射等分析测试手段,对钱家店地区姚家组砂岩黏土矿物的镜下特征、成分及含量进行了系统的观察和研究。【研究结果】钱家店地区姚家组砂岩黏土矿物主要为高岭石,其次为伊利石、蒙皂石,少量绿泥石。黏土矿物是沉积岩中铀富集的重要吸附剂,不同种类的黏土矿物对铀的吸附能力存在一定差异。【结论】姚家组成矿环境经历了成矿早期的酸性环境和成矿晚期的弱碱性环境,不同的黏土矿物之间在此过程中存在着一系列的相互转化关系。黏土矿物含量变化不仅影响着铀储层物性特征,同时也影响着铀的沉淀富集。在黏土矿物吸附作用下,姚家组砂岩成岩过程中,预富集了大量的铀,为钱家店地区形成特大型铀矿床奠定了坚实物质基础。[Objective] The Qianjiadian uranium deposit is located in the southwestern songliao basin and the U-bearing rock series occur in the upper Cretaceous Yaojia Formation. There are a lot of clay minerals in the target strata, so it is very important to reveal the characteristics of clay minerals in sandstone of Yaojia Formation for uranium mineralization.[Methods] In this paper, method of microscopic identification, scanning electron microscopy and X-ray diffraction were used to systematically observe and study the microscopic characteristics, composition and content of clay minerals in the Yaojia Formation sandstones of the Qianjiadian area.Then, characteristics of the clay minerals were discussed in detail. [Results] The clay minerals are mainly kaolinites, followed by smectites, chlorites and illites. Clay minerals are important adsorbents for uranium enrichment in sedimentary rocks, and the adsorption capacity of different clay minerals to uranium is different. [Conclusions] The Yaojia ore-forming environment experienced the acidic environment in the early ore-forming stage and the weakly alkaline environment in the late ore-forming stage. And there are a series of mutual transformation relations between different clay minerals in this process. The change of clay mineral content not only affects the physical properties of uranium reservoir but also influences the enrichment of uranium. Under the action of clay mineral adsorption, a large amount of uranium was pre-enriched in the process of sandstone diagenesis of Yaojia formation, which laid a solid material foundation for the formation of extra-large uranium deposits in Qianjiadian area.

关 键 词：砂岩型铀矿 钱家店地区 黏土矿物 姚家组 松辽盆地 矿产勘查工程 

分 类 号：P619.14[天文地球—矿床学]