SGER: A Pilot Study of Plutonochronology: Rapid Dating of Recent Sediments and Soils using Pu Activities and 240Pu/239Pu Determined by ICPMS.

摘要/ abstract摘要：深部年代学的初步研究：利用铀活度和ICPMS测定的240 / 239铀快速定年沉积物和土壤。对环境中人为污染物年表和清单的研究需要在土壤和沉积物中有一个校准良好的时间表。这些沉积物和土壤剖面最频繁、最可靠的测年方法是使用耗时的放射性计数测量过量的210Pb、137Cs和239+240Pu。由于分析上的困难，使用钚同位素测定最近土壤和沉积物的年代还没有得到更广泛的研究。四极ICPMS在Pu年代学中的应用一直被忽视，这是20世纪90年代同位素地球化学领域最引人注目的错失机会之一，因为ICPMS技术至少在过去十年中已经适合于这项任务。本项目的目标是证明和进一步发展电感耦合等离子体质谱（ICPMS）在土壤和沉积物的Pu年代测定中的应用。这种方法将为137Cs和/或过量210Pb的既定放射性衰变计数提供更快的补充或替代方法。它将检查爱达荷州Coeur DAlene湖和Pine Valley水库（华盛顿公司，UT）的Pu活性和同位素比率剖面。

ABSTRACTA Pilot Study of Plutonochronology: Rapid Dating of Recent Sediments and Soils using Pu Activities and 240 Pu/ 239 Pu Determined by ICPMS.Studies of the chronology and inventory of anthropogenic pollutants in the environment require a well-calibrated timeline in soils and sediments. These sediment and soil profiles are most frequently and reliably dated using time-consuming radiocounting measurements of excess 210Pb, 137Cs, and 239+240Pu. Dating of recent soils and sediments using plutonium isotopes has not been more extensively pursued because of analytical difficulties. The fact that the application of quadrupole ICPMS to Pu chronology has been overlooked represents one of the more striking missed opportunities of the 1990s in isotope geochemistry, as ICPMS technology has been suited to this task for at least the last decade. The goal of this project is to demonstrate and further develop the use of inductively coupled plasma mass spectrometry (ICPMS) in Pu dating of soils and sediments. This approach will provide a much faster complement or alternative to established radiodecay counting of 137Cs and/or excess 210Pb. It will examine Pu activity and isotope ratio profiles in Lake Coeur DAlene, Idaho, and Pine Valley Reservoir (Washington Co., UT).