油页岩中U和Th分布及其赋存状态的研究

利用电感耦合等离子质谱对23个油页岩样品中U和Th含量进行测试,采用浮沉实验和逐级化学提取实验相结合分析了吉林桦甸和罗子沟油页岩样品中U和Th的赋存状态。研究表明,油页岩中铀的含量多小于10×10^-6,平均值为3.92×10^-6,油页岩中钍的含量多小于20×10^-6,平均值为10.51×10^-6。U和Th在油页岩中的丰度略高于在地壳中的丰度,与在沉积岩中的丰度较接近。浮沉实验结果和逐级化学提取结果相当。结果表明,油页岩中U和Th主要存在于无机矿物质中。

Distribution and modes of occurrence of U and Th in oil shale

The concentrations and modes of occurrence of U and Th in 23 oil shale samples from China were studied. The concentrations of U and Th were determined by inductively coupled plasma-mass spectrometry. The occurrence of U and Th in Huadian and Luozigou oil shale was investigated using six-step sequential chemical extract method. The concentrations of U in oil shale are within 10×10^-6 and average of 3.92×10^-6. The concentrations of Th in oil shale are within 20×10^-6 and average of 10.51×10^-6. The abundances of U and Th in oil shale are slightly higher than in crust and close to sedimentary rocks. The experimental results of floating and sinking roughly equal that of the sequential chemical extraction in U and Th. The U and Th in oil shale are mainly existed in minerals.