鄂尔多斯盆地东胜地区侏罗系煤与铀矿关系

鄂尔多斯盆地东胜地区侏罗系煤与砂岩型铀矿在空间上密切共存,为探讨煤与铀矿的关系,进行了广泛的野外调研和系统的室内分析。在煤岩特征、煤的成岩演化和煤地球化学特征研究的基础上,发现从泥炭至褐煤的煤化过程中,铀的含量不断增加;铀含量与煤岩显微组分中的镜质组含量成正比;砂岩成岩矿物与煤化作用有关;煤的微量元素和稀土元素的含量特征与含矿砂岩具一致性。研究认为,在同生成岩阶段和早成岩阶段,煤对铀的作用主要包括吸附作用、络合作用及还原作用;表生成岩阶段,煤对铀的再分配和“保矿”起到积极作用。

Relationship between Jurassic Coal Measures and Uranium Deposits in Dongsheng Area, Ordos Basin

Jurassic coal measures and sandstone uranium deposit directly coexisted in space in Dongsheng area,Ordos basin.In order to discuss the relationship of coal measures and uranium deposit,extensive field exploration and systemic indoor analysis were conducted.Based on the research of coal features,diagenetic succession and geochemical features of coal measures,it is discovered that uranium content continuously increase during the diagenesis stages from turf to lignite and is in direct proportion to content of vitrinite in group macerals of coal,diagenetic minerals of sandstone correlate to coalification,and contents and features of trace element and REE of coal concide with that of uranium-bearing sandstone.It is concluded that effects of coal on uranium include sorption,complexation and revivification in syngenesis and early diagenesis and coal measures have positive effect on redistribution and preservation of uranium deposit in the epidiagenetic stage.