Simultaneous determination of picogram per gram concentrations of Ba, Pb and Pb isotopes in Greenland ice by thermal ionisation mass spectrometry.

A technique has been developed to simultaneously measure picogram per gram concentrations of Ba and Pb by isotope dilution mass spectrometry, as well as Pb isotopic ratios in polar ice by thermal ionisation mass spectrometry. BaPO2(+) and Pb+ ions were employed for these determinations. A calibrated mixture of enriched 205Pb and 137Ba was added to the samples providing an accuracy of better than approximately 2% for Pb/Ba element ratio determinations.