Fraser Canyon
Coordinates: 49°38′00″N 121°25′00″W / 49.63333°N 121.41667°W
The Fraser Canyon is a major landform of the Fraser River where it descends rapidly through narrow rock gorges in the Coast Mountains en route from the Interior Plateau of British Columbia to the Fraser Valley. Colloquially, the term "Fraser Canyon" is often used to include the Thompson Canyon from Lytton to Ashcroft, since they form the same highway route which most people are familiar with, although it is actually reckoned to begin above Williams Lake, British Columbia at Soda Creek Canyon near the town of the same name.
The canyon was formed during the Miocene period (23.7–5.3 million years ago) by the river cutting into the uplifting Interior Plateau. From the northern Cariboo to Fountain, the river follows the line of the huge Fraser Fault, which runs on a north-south axis and meets the Yalakom Fault a few miles downstream from Lillooet. Exposures of lava flows are present in cliffs along the Fraser Canyon. They represent volcanic activity in the southern Chilcotin Group during the Pliocene period and the volcanic vents of their origins have not been discovered.
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