Rapid and precise measurement of carbonate clumped isotopes using laser spectroscopy.

Carbonate clumped isotope abundance is an important paleothermometer, but measurement is difficult, slow, and subject to cardinal mass () interferences using isotope ratio mass spectrometry (IRMS). Here, we describe an optical spectroscopic measurement of carbonate clumped isotopes. We have adapted a tunable infrared laser differential absorption spectrometer (TILDAS) system to measure the abundances of four CO isotopologues used for clumped isotope thermometry.