2024 Volume 73 Issue 1 Pages 47-59
The combination of isotopes, a radio isotope and a stable isotope can be used for dating, like 14C-dating. This article discusses the possibility of dating using iodine isotope system (129I and 127I). Since 129I is a long lived radio isotope (half life=15.7 Myr), the iodine isotope system is a potential dating tool for large time scale, which had been initially proposed by Fehn (Rochester University) in Science article published in 2,000. He tried to determine the formation age of methane hydrates in Blake ridge, the United States using 129I/127I. For the dating, we should know the initial isotopic ratio and he used the value proposed by J. Moran in 1998. However, for the initial ratio, there still is under debate. This article discusses in details the conditions which make possible the dating. As an indispensable measurement method for detection of environmental 129I, Accelerator Mass Spectrometry is also explained in details, hardware configuration, physical principle, and pre-treatment of environmental samples.
