The Paleoproterozoic Fedorov-Pana Layered PGE Complex of the Northeastern Baltic Shield, Arctic Region: New U-Pb (Baddeleyite) and Sm-Nd (Sulfide) Data

摘要

For the first time zircons have been extracted from gabbro-norite of a lower layered horizon of the West Pana Massif in the Pt-Pd Kievei deposit of the Fedorov-Pana Layered Complex. Those zircons have been used for U-Pb dating along with Sm-Nd age determination on sulfide minerals. The obtained new isotopic data are a U-Pb zircon age of 2500 +/- 4 Ma, while the Sm-Nd (mineral and whole-rock) isochron yielded 2483 +/- 86 Ma. These results correspond to the first phase of the Pt-Pd reef complex formation in the Layered Complex. The Pt-Pd reef formation has been dated by U-Pb baddeleyite and zircon analyses in the East Pana Massif to 2464 +/- 12 Ma. The 2485-2464 Ma time span corresponds to the second phase of the Pt-Pd reef formation in the Fedorov-Pana ore cluster.