A landscape forged by fire
The Mount Edziza Volcanic Complex is a sprawling volcanic field in northwestern British Columbia that covers approximately 1,000 square kilometers. Its formation began around 7.5 million years ago as the Earth's crust in the region began to stretch and thin, a process known as continental rifting. This activity has occurred over five distinct magmatic cycles, creating a landscape of overlapping shield volcanoes, stratovolcanoes, lava domes, and more than 30 cinder cones.
The base of the complex is a broad, steep-sided lava plateau 65 kilometers long and 20 kilometers wide. Rising from this plateau are several major volcanic centers. The main peak, Mount Edziza, is a stratovolcano with an elevation of 2,786 meters and a 2-kilometer-wide, ice-filled caldera at its summit. The complex also includes Armadillo Peak, Ice Peak, and the Spectrum Range. The Spectrum Range is known for its intensely colored rocks—red, yellow, and purple colors created by the staining of rhyolite by sulfurous waters.
Volcanism has been nearly continuous for millions of years, with some activity occurring under and in contact with glacial ice sheets. This interaction between lava and ice created formations like hyaloclastites and pillow lavas. While the main Edziza cone has been dormant for millennia, smaller eruptions have occurred much more recently. Perfectly formed cinder cones, such as Eve Cone which rises 150 meters above the plateau, are estimated to be only around 1,300 years old. The most recent lava flows in the complex are thought to have occurred about 1,000 years ago.
A 10,000-year-old resource
For at least 10,000 years, the Mount Edziza complex has been a important site for Indigenous peoples, particularly the Tahltan Nation. The name "Edziza" itself is a Tahltan word meaning "cinders." The complex contains at least 10 distinct flows of obsidian, a volcanic glass that was a highly valued material for making sharp tools and weapons. Archaeological evidence shows that obsidian from Edziza was a major trade item across a vast network, with artifacts found as far away as Alaska and northern Alberta.
Archaeological surveys have identified extensive quarry sites, with some areas like Goat Mountain and Artifact Valley containing dense carpets of obsidian fragments, numbering between 1,000 to 4,000 items per square meter. The oral histories of the Tahltan people include accounts of volcanic eruptions witnessed by their ancestors, a history supported by geological evidence of recent activity.
Recent archaeological work in melting ice patches within Mount Edziza Provincial Park has uncovered perishable artifacts associated with the obsidian quarrying. Discoveries include stitched birch-bark containers for carrying obsidian, wooden walking staffs, and parts of a hide boot, with some items radiocarbon-dated to as old as 7,000 years. These finds confirm the long and continuous human presence in this volcanic landscape, centered on the procurement of this important geological resource.