Laser probe ⁴⁰Ar/³⁹Ar dating: History and development from a technical perspective

详细信息    查看全文

• 作者：Hironobu Hyodo
• 关键词：Laser probe ; ⁴⁰Ar/³⁹Ar dating ; Step heating ; Single spot dating ; Detection limit
• 刊名：Gondwana Research
• 出版年：2008
• 出版时间：December 2008
• 年：2008
• 卷：14
• 期：4
• 页码：609-616
• 全文大小：551 K

文摘

The ⁴⁰Ar/³⁹Ar method using a laser probe opened the door to microscale measurements and diffusion profiles frozen in samples. In the first decade since the initial application of a laser for ⁴⁰Ar/³⁹Ar dating in 1973, practical applications have been few. This is due not only to the fact that the laser and vacuum technologies were immature but that mass spectrometry was also in its infancy. In those days, the sensitivity of a mass spectrometer was generally insufficient to measure the small amount of argon degassed from a geological sample by a laser. These problems have subsequently been solved by new technologies. To understand their current status, a brief history of their development is outlined. This outline focuses on the required detection limit in micro scale measurement, practical approaches for accurate measurement are explained through examples in our laboratory specifically relating to the technical aspects of ⁴⁰Ar/³⁹Ar dating.