Crustal growth and reworking during Lapland–Kola orogeny in northern Fennoscandia: U–Pb and Lu–Hf data from the Nattanen and Litsa–Aragub-type granites

• The Nattanen– and Litsa–Aragub-type granites were emplaced between 1.79 and 1.76 Ga.
• Hf isotope data indicate a dominantly Archaean crustal source.
• The granites are part of the magmatism related to the assembly of Nuna supercontinent.

In this paper we present new zircon U–Pb, Lu–Hf and REE data for Palaeoproterozoic intrusions (Nattanen– and Litsa–Aragub-type granites) of the Fennoscandian shield, to obtain a more detailed understanding of their petrogenesis. The intrusions form a chemically homogenous group of SiO2-rich A-type, post-kinematic granites that were emplaced between 1.79 and 1.76 Ga. The Hf isotopes indicate that the source was dominated by an Archaean crustal component although a mantle contribution cannot be ruled out. The isotopic data further constrain the evolution of the Archaean and Palaeoproterozoic crust and the assembly of the Nuna (Columbia) supercontinent. The Nattanen– and Litsa–Aragub-type granites are part of a voluminous phase of granitoid magmatism in Fennoscandia at 1.8–1.75 Ga, reflecting large-scale processes at the margin of the Nuna supercontinent.