Why measure stable isotopes?
The ratio of rare, heavy stable isotopes to common light isotopes provides unique tracers of physical and biological processes. The natural abundance of stable isotopes in the environment has been used to study:
A basic introduction to environmental applications of stable isotopes can be found here.
How are stable isotopes measured?
Because rare isotopes are present in such small quantities in the environment, isotopes are expressed as ratios (heavy/light relative to a common standard). Specialized Isotope Ratio Mass Spectrometers (IRMS) are used to measure these ratios. UC Irvine has five IRMS with interfaces to analyze several different types of samples. A full list of instrumentation can be found here.
