Accelerator Mass Spectrometry ¹⁴C Determination in CO₂ Produced from Laser Decomposition of Aragonite

Authors

Brad E. Rosenheim, Woods Hole Oceanographic InstitutionFollow
Simon R. Thorrold, Woods Hole Oceanographic Institution
Mark L. Roberts, Woods Hole Oceanographic Institution

Document Type

Article

Publication Date

2008

Digital Object Identifier (DOI)

https://doi.org/10.1002/rcm.3745

Abstract

The determination of ¹⁴C in aragonite (CaCO₃) decomposed thermally to CO₂ using an yttrium-aluminum-garnet doped neodymium laser is reported. Laser decomposition accelerator mass spectrometry (LD-AMS) measurements reproduce AMS determinations of ¹⁴C from the conventional reaction of aragonite with concentrated phosphoric acid. The lack of significant differences between these sets of measurements indicates that LD-AMS radiocarbon dating can overcome the significant fractionation that has been observed during stable isotope (C and O) laser decomposition analysis of different carbonate minerals. The laser regularly converted nearly 30% of material removed into CO₂ despite it being optimized for ablation, where laser energy breaks material apart rather than chemically altering it. These results illustrate promise for using laser decomposition on the front-end of AMS systems that directly measure CO₂ gas. The feasibility of such measurements depends on (1) the improvement of material removal and/or CO₂ generation efficiency of the laser decomposition system and (2) the ionization efficiency of AMS systems measuring continuously flowing CO₂.

Was this content written or created while at USF?

No

Citation / Publisher Attribution

Rapid Communications in Mass Spectrometry, v. 22, issue 21, p. 3443-3449

Scholar Commons Citation

Rosenheim, Brad E.; Thorrold, Simon R.; and Roberts, Mark L., "Accelerator Mass Spectrometry ¹⁴C Determination in CO₂ Produced from Laser Decomposition of Aragonite" (2008). Marine Science Faculty Publications. 2454.
https://digitalcommons.usf.edu/msc_facpub/2454