Weddell Fan and associated abyssal plain, Antarctica: Morphology, sediment processes, and factors influencing sediment supply

The newly discovered Weddell Fan, Antarctica, covers 0.75 million km2. The adjacent continental shelf is characterized by deep, rugged topography; the inner shelf is covered by a grounded polar ice sheet. The upper fan has numerous deep, V-shaped canyons that intersect a slope-base, leveed fan valley. Piston cores from the valley contain disorganized gravel grading upward into graded gravel and sand. Levee cores contain interbedded hemipelagic sediments and fine-grained turbidites. The lower fan is sand-rich. Sediment supply to the fan apparently occurred before development of glacial shelf topography and during a more temperate glacial setting.