 The Archean Red Lake greenstone belt in western Ontario consists of basaltic and komatiitic volcanics ranging in age from 2,925 to 2,940 million years old and younger rhyolite-andesite volcanics ranging in age from 2,730 to 2,750 million years old.It is situated in the western portion of the Uchi Subprovince, a volcanic sequence comprising a number of greenstone belts.The 1884- to 1870‑million-year-old Circum-Superior Belt constitutes a large igneous province extending for more than from the Labrador Trough in Labrador and northeastern Quebec though the Cape Smith Belt in northern Quebec, the Belcher Islands in southern Nunavut, the Fox River and Thompson belts in northern Manitoba, the Winnipegosis komatiite belt in central Manitoba, and on the southern side of the Superior craton in the Animikie Basin of northwestern Ontario.