Automated Stage for Fission-Track Dating

9351384 Garver一个用于裂变轨道测年的自动阶段系统正在被本科生使用。裂变径迹测年包括确定在锆石或磷灰石晶体中随时间自然产生的化石径迹的密度。此外，还需要确定晶体中铀的含量，因为径迹密度与年龄和铀浓度成正比。这是通过在样品上放置云母片并照射样品以产生自发轨迹来实现的；云母薄片上自发径迹的密度与铀浓度成正比。自动平台快速精确地移动显微镜平台，绝对精度为10米。考虑到这种节省大量时间和易于使用的方法，我们正在将裂变径迹定年法引入我们的地球化学课程，并在项目中让学生测定制备样品的日期并解释其意义。此外，该系统被广泛应用于我们的毕业论文项目。* * * y

9351384 Garver An automated stage system for fission-track dating is being used by undergraduate students. Fission-track dating involves determining the density of fossil tracks that have occurred naturally over time in either zircon or apatite crystals. Additionally, however, one needs to determine the amount of uranium in the crystal because track density is proportional to age and uranium concentration. This is accomplished by placing a mica flake over the sample and irradiating the sample to produce spontaneous tracks; the density of spontaneous tracks on the mica flake is proportional to the uranium concentration. The automated stage quickly and precisely moves the microscope stage with an absolute accuracy of 10 m. Given this considerable time savings and ease of use, we are introducing fission-track dating into our Geochemistry classes with projects in which students date prepared samples and interpret their significance. Additionally, the system is being used extensively in our senior thesis program. ***y