Faulting commonly influences the geomorphology of submarine canyons that occur on active continen... more Faulting commonly influences the geomorphology of submarine canyons that occur on active continental margins. Here we examine the geomorphology of canyons located on the continental margin off Haida Gwaii, British Columbia, that are truncated on the mid-slope (1,200–1,400 m water depth) by the Queen Charlotte Fault Zone (QCFZ). The QCFZ is an oblique strike-slip fault zone that has rates of lateral motion of around 50–60 mm/yr and a small convergent component equal to about 3 mm/yr. Slow subduction along the Cascadia Subduction Zone has accreted a prism of marine sediment against the lower slope (1,500 to 3,500 m water depth), forming the Queen Charlotte Terrace, which blocks the mouths of submarine canyons formed on the upper slope (200 to 1,400 m water depth). Consequently, canyons along this margin are short (4 to 8 km in length), closely spaced (around 800 m), and terminate uniformly along the 1,400 m isobath, coinciding with the primary fault trend of the QCFZ. Vertical displacement along the fault has resulted in hanging canyons occurring locally. The Haida Gwaii canyons are compared and contrasted with the Sur Canyon system, located to the south of Monterey Bay, California, on a transform margin, which is not blocked by any accretionary prism, and where canyons thus extend to 4,000 m depth, across the full breadth of the slope.
Faulting commonly influences the geomorphology of submarine canyons that occur on active continen... more Faulting commonly influences the geomorphology of submarine canyons that occur on active continental margins. Here we examine the geomorphology of canyons located on the continental margin off Haida Gwaii, British Columbia, that are truncated on the mid-slope (1,200–1,400 m water depth) by the Queen Charlotte Fault Zone (QCFZ). The QCFZ is an oblique strike-slip fault zone that has rates of lateral motion of around 50–60 mm/yr and a small convergent component equal to about 3 mm/yr. Slow subduction along the Cascadia Subduction Zone has accreted a prism of marine sediment against the lower slope (1,500 to 3,500 m water depth), forming the Queen Charlotte Terrace, which blocks the mouths of submarine canyons formed on the upper slope (200 to 1,400 m water depth). Consequently, canyons along this margin are short (4 to 8 km in length), closely spaced (around 800 m), and terminate uniformly along the 1,400 m isobath, coinciding with the primary fault trend of the QCFZ. Vertical displacement along the fault has resulted in hanging canyons occurring locally. The Haida Gwaii canyons are compared and contrasted with the Sur Canyon system, located to the south of Monterey Bay, California, on a transform margin, which is not blocked by any accretionary prism, and where canyons thus extend to 4,000 m depth, across the full breadth of the slope.
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