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How do submarine canyons cut into continental shelves and continental slopes?

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continental shelf The broad, gentle pitch of the continental shelf gives way to the relatively steep continental slope. The more gradual transition to the abyssal plain is a sediment-filled region called the continental rise. The continental shelf, slope, and rise are collectively called the continental margin.

Submarine canyons are narrow, steep-sided valleys that incise continental slopes and continental shelves. Their formation is attributed to a combination of subaerial and marine processes.1

During the Pleistocene Epoch, lower sea levels exposed the continental shelves, allowing rivers to cut the heads of many canyons through subaerial erosion. However, subaerial erosion alone is insufficient to explain the deep excavation of these features down to the seafloor.12

The primary agents responsible for forming and maintaining these canyons are marine processes, specifically the erosion and transport of sediment by turbidity currents. These currents are often triggered by the slumping of unconsolidated rock material near the canyon heads. Additionally, deep-water currents carrying high concentrations of suspended sediment, as well as avalanche-like movements of loose sedimentary material, continue to carve and maintain the canyons as they extend down the continental slopes.12