Chilcotin Group

Map showing geological formations related to the Canadian Cascade Arc
Basalt lava in Chasm Provincial Park

Chilcotin Plateau basalts cover a large area in British Columbia. Basaltic lava formed a volcanic plateau running parallel with the Garibaldi Volcanic Belt, about 150 km from the ocean.

During the Miocene and Pliocene, a volcanic field occurred in British Columbia's Interior Plateau. The basalt is assumed to cover up to 50,000 km2 of the Pacific Northwest. It forms a medium-sized large igneous province, of volume 3300 km3.[1]

Volcanism still continues from time to time. Eruptions were most vigorous 6–10 million years ago (mya) and 2–3 mya, when most of the basalt was released. Smaller eruptions continued from 1.6 mya to 0.01 mya.[2]

Chilcotin Group Media

References