Deep-Sea Fan

A deep-sea fan is a large, fan-shaped body of sediment built on the continental rise and abyssal plain at the mouth of a submarine canyon. Turbidity currents flowing down the canyon spread out and deposit, constructing leveed channels on the upper fan, channel-lobe systems on the mid fan, and sheet-like lobes on the lower fan, with grain size fining basinward. The Bengal Fan, fed by the Ganges-Brahmaputra, is the world’s largest at over 3,000 kilometers long. Fans are the main sink for terrigenous sediment delivered to the deep ocean and host major reservoir sands. The deposits are stacked turbidites.