 The central portion of the Anahim Volcanic Belt contains three complex shield volcanoes, known as the Rainbow, Ilgachuz, and Itcha ranges.These fairly dissected shield volcanoes lie on the northern end of the Chilcotin Group lava plateau and distal lava flows at the margins of the shield volcanoes merge imperceptibly with flat-lying lava flows comprising the Chilcotin Group lava plateau.Unlike the Chilcotin Group basalt, which is not associated with any felsic derivatives, the volcanoes of the central Anahim Volcanic Belt are markedly bimodal, comprising a mixed assemblage of basalt and peralkaline silicic rocks.