Development Completion of Rare Krypton Isotope Analysis for the Geosciences and First Validation Measurements

[01:19110 . thonnard]该奖项为完成测量两种稀有氪同位素Kr-81和Kr-85丰度所需的技术开发提供了部分支持。这些同位素在大气中的浓度是稳定和已知的，是各种环境研究的潜在理想示踪剂。Kr-81的半衰期为229,000年，可以确定在20,000到1,000,000年的时间范围内，古代冰或地下水与大气分离了多长时间。同样，Kr-85的半衰期为10.8年，可以在1至50年的时间范围内确定隔离时间。例如，这些类型的测量可以提供对地下水运动的重要见解，确定污染渗透的途径，并为整体资源管理提供输入。由于其化学惰性，预计氪同位素将通过消除与地下环境相互作用的复杂性，提供比其他化学活性示踪剂更可靠的结果。这项资助的工作包括完成对现有仪器的必要改进，并将该技术应用于几个重要的地下水问题，以突出其效用

0119110ThonnardThis award provides partial support to complete development of technology necessary for measuring the abundance of two rare krypton isotopes, Kr-81 and Kr-85. These isotopes, whose concentration in the atmosphere is stable and known, are potentially ideal tracers for a variety of environmental studies. Kr-81, with a 229,000 year half-life, can determine how long ancient ice or ground water has been isolated from the atmosphere in the 20,000 to 1,000,000 year time range. Similarly, Kr-85, with its 10.8 year half-life, can determine isolation times in the 1 to 50 year time range. These type of measurements can, for instance, provide important insight into the movement of groundwater, identify pathways for pollution infiltration, and provide input to overall resource management. Being chemically inert, it is anticipated that the krypton isotopes will provide more reliable results than other, chemically active tracers, by eliminating the complexity of interactions with the underground environment. The work sponsored by this grant includes completion of the necessary improvements to existing instrumentation, and application of the technique to several important groundwater problems to highlight its utility.***