前言铀、镭和钍具有不同的放射性强度,借助于此种强度差别可以用放射性测量方法对该三种元素进行定性和定量测定。放射性测量方法比研究天然岩体放射性化学方法、矿物鉴定法、放射性照象法及其他方法具有根本的优越性,因为这些方法效率较高,同时在野外条件下可用此种方法进行测量。我们把铀、钍和鐳定量测定的总任务分为两个具有不同实际意义的任务——铀镭不平衡矿石中铀和鐳的测定;铀釷混合矿石中铀和釷的测定。 Foreword Uranium, radium and thorium have different radioactive intensities, by means of which the three elements can be qualitatively and quantitatively determined by radiometric methods. Radiometric methods have fundamental advantages over the study of radioactive chemical methods, mineral identification methods, radiographic methods and other methods of natural rock mass because these methods are more efficient and can be measured in this field under field conditions. We divide the general tasks of quantitative determination of uranium, thorium and radium into two tasks of different practical significance - the determination of uranium and radium in uranium-radium-unbalanced ores; the determination of uranium and thorium in uranium-thorium mixed ores.