Rare-earth element modelling of Archean meta-igneous and igneous rocks, Lake Despair area, northwestern Ontario

Archean felsic to intermediate meta-igneous rocks from the Lake Despair area, northwestern Ontario, have highly-fractionated REE patterns (LaN/LuN 10–100). They are rich in LREEs (ca. 40–100 × chondrites) and poor in HREEs (ca. 1–7 × chondrites). Simple models for the REEs suggest eclogite—quartz eclogite parents for these rocks. The Footprint Gneiss, the major rock type of the Rainy Lake Batholith, was formed by limited melting (ca. 10%) of a …