U–Pb zircon dating by laser ablation-MC-ICP-MS using a new multiple ion counting Faraday collector array
Abstract
This study reports U–Pb geochronological data for zircon obtained by laser ablation-multi-collector-ICP-MS using a new collector block design that includes three ion counters and twelve Faraday buckets. The collector configuration allows for simultaneous detection of ion signals from mass 238U to 203Tl, an important factor for the achievement of highly precise and reproducible Pb–Pb and Pb–U ratios. The main advantage of the multiple ion counting system is the capability to readily measure low Pb ion signals (<1 × 106 counts per second) resulting from single spot analyses of ≤40 microns (and corresponding small sample volumes). The latter is an extremely important feature when deciphering multiple domains in complexly zoned zircon populations. A comparative study was conducted between analytical protocols involving non-Tl- and Tl-doped