Measurement of the carbon content of silicate glasses using the ^(12)C(d,p_0)^(13)C nuclear reaction

Abstract

Carbon dioxide is a significant dissolved component in a wide range of magmas and ubiquitous in gasses associated with volcanism. This fact has motivated extensive study of the influence of CO_2 on the petrogenesis of many magma types. Despite its importance, the absolute concentrations of dissolved C in silicate glasses quenched from these magmas are not well known. Standard carbon analysis techniques (e. g., gas manometry, quadruple mass spectrometry, gas chromatography) have been applied to natural and synthetic C-bearing glasses, but a comparison of the results of these techniques shows wide discrepancies. These bulk analytic techniques are destructive and require relatively large samples; in addition, the effects of crystals, alteration phases, and C in bubbles (versus C dissolved in the glass) are often difficult to evaluate.