Isotope ratio mass spectrometry (IRMS) is a specialist field of mass spectrometry, concerned with measuring the relative abundance of atomic isotopes.
Mass spectrometry Accelerator mass spectrometry Isotope Isotopomers Sector instrument Vienna Standard Mean Ocean Water Belemnoidea Alfred O. C. Nier Table of nuclides Carbon-13 Foraminifera Paleoclimatology Aquifer Deuterium Atomic number Hydrology Mole (unit) Atom Hydrogen