Photograph by B. Edwards
Photograph by B. Edwards
Mathew's Tuya, the flat-topped mountain in the center of the photograph, is a somewhat subdued volcanic landgorm. It is one of six subglacial volcanoes close to Tuya Lake, in northcentral British Columbia. It has been partly glaciated, so it is probably older than 10,000 y.b.p. The other volcanoes in the area include Tuya Butte, South Tuya, and Ash Mountain. The volcanoes in the Tuya region of northwestern British Columbia form part of the northern Cordilleran volcanic province of northwestern Canada (Edwards & Russell 2000).
Photograph by B. Edwards
The picture of Mathew's tuya above illustrates the unique shape of subglacial volcanoes that have flat tops (also refered to as tuyas). The lower slopes of the volcano comprise subglacially-erupted pillow lava and hyaloclastite, but the flat top is capped by subaerial lava flows (Simpson 1996).
-Ben Edwards, Grand Valley State University, MI
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Tuya: a subglacial volcano in northwestern British Columbia
[B.Sc. Thesis]: Vancouver, University of British Columbia, 97 p.
