ABSTRACT

A method for in situ rutile U-Pb dating was developed using a multiple-collector (MC) ICPMS coupled to an excimer laser-ablation system. Compared with single collector Quadruple ICPMS used by previous in situ rutile U-Pb dating studies, the Neptune Plus MC-ICPMS used in this study has higher sensitivity and is capable of simultaneous acquisition of all the isotope signals required for rutile U-Pb dating. These advantages are important to achieve precise and reproducible in situ U-Pb dating results for rutiles, which typically contain low abundances of U and radiogenic Pb. The analytical results in this study on three reference rutile standards (R10, JDX and DXK) and one nature rutile sample (07RU3) agree with literature/known values, thereby demonstrating that this technique can yield precise and accurate U-Pb dating results for Paleozoic to Paleoproterozoic rutile, even with ~1 ppm U.