Abstract
A dissected terrain resembling a shelf-edge canyon system with individual canyons up to 100 m in relief, 3 km in width, and 10 km in length is found along the south flank of the Cascadia Channel within the central Blanco Transform zone. The channels apparently formed from a combination of downcutting from turbidity currents off the Blanco Ridge and from backcutting due to mass-wasting. The relationships between the transform tectonics and the formation of the canyon are presented in a model which proposes both a direct link via triggering of slides from earthquakes and an indirect link associated with lowering the local base level of Cascadia Channel, thalweg downcutting, and wall-steepening leading to increased mass-wasting.
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Embley, R.W. A locally formed deep ocean canyon system along the Blanco Transform, Northeast Pacific. Geo-Marine Letters 5, 99–104 (1985). https://doi.org/10.1007/BF02233934
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DOI: https://doi.org/10.1007/BF02233934