Astoria Fan

The Astoria Fan is a submarine fan. It has sediment, radiating asymmetrically southward from the mouth of the Astoria Canyon.

Shape

From Astoria Canyon's mouth, the fan extends about to its western end, which is the Cascadia Channel. The fan proper ends south of the canyon mouth, although its depositional basin extends southward another to the Blanco fracture zone.

Astoria Fan is generally asymmetrical. It extends roughly west of the mouth of Astoria Canyon, and about north, to Willapa Channel. Others trace different dimensions.

Headed west, the fan crosses the continental shelf, trending sinuously down to the base of the continental slope. Near Astoria Canyon, it is at a depth of . The fan is approximately long. It varies in width from to . It has numerous tributaries. The fan extends about to its western boundary, which is the Cascadia Channel.

Notes on the creation of the Astoria Fan

Ash from the eruption of Mount Mazama has been found, in Astoria Fan. It may have been cut in the Pleistocene. It appears the Missoula Floods helped carve the fan.

Astoria Fan merges into Astoria Canyon, west of the Columbia River mouth. In the past, buried Pleistocene channels appear to have connected the two.

Nearby submarine canyons

All of the following submarine canyons are near, headed north to south:

Clayoquot Canyon Father Charles Canyon Loudon Canyon Barkely Canyon Nitinat Canyon Juan de Fuca Canyon Quileute Canyon Quinault Canyon Grays Canyon Guide Canyon Willapa Canyon Astoria Canyon

Astoria Fan

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