Klondikers on raft navigating Miles Canyon on the Yukon River, Yukon Territory, circa 1898

• Other Authors: University of Washington Libraries, Special Collections Division
• Format: Other/Unknown Material
• Language: unknown
• Subjects: Canyons > Yukon; Rivers > Yukon; Rafts > Yukon; Miles Canyon (Yukon); Yukon River (Yukon and Alaska); Blanchard; Canada; Miles Canyon; White Pass; Whitehorse Rapids; Yukon; Whitehorse; Yukon river; Alaska
• Online Access: http://cdm16786.contentdm.oclc.org:80/cdm/ref/collection/alaskawcanada/id/635

On verso of image: Miles Canyon, 1898. Mr. G.G. Blanchard, White Pass and Yukon Route, Seattle, Wash. Filed in Yukon Territory The basaltic lava exposed by Miles Canyon originated from a low volcanic vent approximately 8km to the south (see map). This lava flowed into the ancient Yukon River valley about 8.5 millions years ago. Drilling near Whitehorse rapids shows that the layer of lava reaches 110 meters thick. Only the top 10 meters of this layer is currently visible at the bridge. Prior to the building of the Whitehorse dam in 1959, the water level was about 10 meters lower, exposing much more of the lava.