High Precision 234U-230Th Dating of Corals and Marine Chemistry of Rare Earth Elements, Actinide Elements and Lead

已开发出在-109原子水平上测定234U和230Th的质谱学技术，其精密度约为0.5%。现在可以获得关于珊瑚的有用年龄数据的时间范围从50年到大约50万年。这种方法将应用于珊瑚和海相碳酸盐的测年。该方法将应用于珊瑚和海相碳酸盐的测年。主要目标是确定最后一次间冰期的准确时间，并研究新构造。调查人员还将继续研究稀土元素(REE)、鳗系元素(ACE)和铅的海洋化学。这些研究的结果将增进我们对这些元素从大陆向海洋和洋壳的运输以及这些核素对研究时间尺度和重要地质过程的有用性的认识。

Techniques have been developed for mass spectrometric determination of 234U and 230TH at the level of - 10 9 atoms to about 0.5% precision. The time range over which useful age data on corals can be obtained now ranges from 50 to about 500,000 years. This methods will be applied to dating of corals and marine carbonates. This method will be applied to dating of corals ad marine carbonates. The main objectives are to determine the precise timing of the last interglacial period and study neotectonics. The investigators will also continue to study the marine chemistry of rare earth elements (REE), actinide elements (ACE) and lead. The results of these studies will improve our knowledge of the transport of these elements from the continent to the ocean and to the oceanic crust and the usefulness of these nuclides for the study of time scales of time important geological processes.