Duel inlet mat 253 stable isotope ratio mass spectrometer

Powdered samples were analyzed with a Gas Bench II linked to a Thermo Finnigan duel-inlet MAT 253 Stable Isotope Ratio Mass Spectrometer. Isotopic data were reported according to the VPDB international standard, with analytical precision to ±0.4‰.

Isotopic analyses were performed by Curtis McKinney, professor of geology, Miami-Dade College, Miami, Florida. Thick-section wafers of Tanis acipenseriform bone were incrementally sampled from core to bone surface with a New Wave Research Micromill using a Brasseler tungsten carbide mill bit along a drill transect perpendicular to the surface of the bone. The drill bit was cleaned after each spot-sample. Samples were analyzed using a Gas Bench II linked to a Thermo Finnigan duel-inlet MAT 253 Stable Isotope Ratio Mass Spectrometer. C and O isotopic ratios were reported according to the VPDB international standard, with precision of ± 0.3‰.