Pb nanospheres in ancient zircon yield model ages for zircon formation and Pb mobilization.

ABSTRACT: Nanospheres of lead (Pb) have recently been identified in zircon (ZrSiO₄) with the potential to compromise the veracity of U-Pb age determinations. The key assumption that the determined age is robust against the effects of Pb mobility, as long as Pb is not lost from the zircon during subsequent geological events, is now in question. To determine the effect of nanosphere formation on age determination, and whether analysis of nanospheres can yield additional information about the timing of both zircon growth and nanosphere formation, zircons from the Napier Complex in Enderby Land, East Antarctica, were investigated by high-spatial resolution NanoSIMS (Secondary Ion Mass Spectrometry) mapping. Conventional SIMS analyses with >µm resolution potentially mixes Pb from multiple nano

SUBMITTER: Lyon IC 

PROVIDER: S-EPMC6757063 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature