Neoarchean leucogranitoids of the Kianta Complex, Karelian Province, Finland: Source characteristics and processes responsible for the observed heterogeneity

► The ca. 2.7 Ga leucogranitoids were mainly derived from local TTGs. ► The compositional scatter, in both major and trace-elements is considerable. ► Melting was caused by thickening of the crust in response to collisional tectonics. ► Melting occurred under water-fluxed conditions. ► Potential fluid sources are lower crust and late mantle derived intrusives.