According to National Geographic, Island slope is the gently sloping landform leading from the edge of a continent, under the sea, to flat ground. The continental slope is where submarine canyons are found. They act like streams on the continents - cutting channels into the slopes from eroded sediments. This happens with the movement of lithosphere (rigid outermost shell) plates under the sea. Submarine canyons create a great deal of the sediments found in the abyssal plains.