Evolution of the Belomorian Belt: NORDSIM U-Pb zircon dating of the Chupa paragneisses, magmatism, and metamorphic stages
The U-Pb systematics of accessory zircons were studied by secondary ion mass spectrometry (NORDSIM ion microprobe). This study revealed two main age groups of terrigenous zircons, 3000 and 2900 Ma, in the metasedimentary rocks of the Chupa nappe of the Belomorian belt. Zircon older than 3200 Ma was not found, which is consistent with the available Sm-Nd model ages. Older terrigenous zircons (3100-