High-sensitivity sulfur isotopic measurements for Antarctic ice core analyses.

Rationale: Sulfur is widely distributed in nature, and sulfur isotopic measurements have been applied to elucidate the origin and transport of sulfuric compounds in the lithosphere, biosphere, and atmosphere. Analyses of samples containing small amounts of sulfur, such as the Antarctic ice core samples analyzed herein, require a high-sensitivity analytical method.

Methods: We developed a high-sensitivity sulfur isotopic ratio (δ S value) analytical system equipped with an elemental analyzer, a cryo-flow device, and an isotope ratio mass spectrometer, and established a measurement and calibration procedure.