Seminarium Fizyki Jądra Atomowego
sala 1.01, ul. Pasteura 5
2019-10-17 (10:15) 
dr hab. Monika Kusiak (Instytut Geofizyki PAN w Warszawie)
Frozen in time – Pb nanospheres in zircon
Heterogeneous Pb distribution in zircon and formation of Pb nanospheres has been identified for the first time in rocks from Enderby Land in Eastern Antarctica. Studies on zircon grains from various localities documented presence of Pb clusters and/or Pb nanospheres with a frozen 207Pb/206Pb ratio giving values significantly higher than zircon host and affecting precise U-Pb age estimates. Recent studies have shown that this little recognized nanoscale phenomenon is in fact widespread in zircon from high-grade metamorphic rocks and might compromise U-Pb geochronology.