Determination of rare earth elements in Precambrian sediments at Isua by inductively coupled plasma mass spectrometry

Abstract
Inductively coupled plasma mass spectrometry (ICP-MS) was applied to the determination of rare earth elements (REEs) in Precambrian sediments which contain high concentrations of iron [1.5–62% measured by instrumental neutron activation analysis (INAA)]. Although a large suppression effect was observed owing to a huge amount of iron, the suppression effect was corrected for by using both In and Bi as internal standards, and reliable analytical results could be obtained. It was found that the interference of oxide ions was not so significant for the determination of REEs. The REE data obtained by ICP-MS are in relatively good agreement (within 10%) with those by INAA. The precision of the analytical results obtained by ICP-MS was 1–14% when using internal standards.