【摘 要】
：
1. ObjectivernBecause of the characteristics of multistage mineralization, long duration, relatively new age, and complicated occurrence of ore minerals, dating of sandstone-type uranium deposits has been a challenging problem. For a long time, the whole-
【机 构】
：
Tianjin Center,China Geological Survey,Ministry of Natural Resources,Tianjin300170,China;Key Laborat
论文部分内容阅读
1. ObjectivernBecause of the characteristics of multistage mineralization, long duration, relatively new age, and complicated occurrence of ore minerals, dating of sandstone-type uranium deposits has been a challenging problem. For a long time, the whole-rock U-Pb isochronal method has been used in the dating of sandstone-type uranium deposits, but its accuracy has been questioned by experts. With the development of large-scale equipment and improved analytical techniques, it is now possible to identify minerals in situ for U-Pb isotope dating. Fayek M\'s team at the University ofManitoba,Canada,hasdevelopedamethodforin situU-Pb isotope analysis using secondary ion mass spectrometry, achieving good results in the dating of uranium minerals from unconformable and pegmatite-type uranium deposits (Fayek M et al., 2002). However, secondary ion mass spectrometry has many disadvantages, such as expensive equipment, slow analysis speed, a high matrix effect, a lack of standard materials, and demanding sample requirements. Because of this,theauthor\'steamintroducedanin situdatingmethodby femtosecond laser ablation multicollector inductively coupled plasma mass spectrometry (femtosecond LA-MC-ICP-MS), which has advantages such as high accuracy, reduced matrix effects, fast analysis speed, and wide adaptability.
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