The Aleutian Basin is an oceanic basin under the southwestern

Bering Sea The Bering Sea (, ; rus, Бе́рингово мо́ре, r=Béringovo móre) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasses on Earth: Eurasia and The Amer ...

. While the northeastern half of the Bering Sea overlies the

North American Plate The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacifi ...

in relatively shallow water, the Aleutian Basin consists of oceanic plate—the remnant of the

Kula Plate The Kula Plate was an oceanic tectonic plate under the northern Pacific Ocean south of the Near Islands segment of the Aleutian Islands. It has been subducted under the North American Plate at the Aleutian Trench, being replaced by the Pacific ...

that was mostly

subducted Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...

under the North American Plate.New Views of the U.S. Continental Margins (University of New Hampshire)
/ref> Subduction of the Kula Plate ceased after the creation of the

Aleutian Trench The Aleutian Trench (or Aleutian Trough) is an oceanic trench along a convergent plate boundary which runs along the southern coastline of Alaska and the Aleutian islands. The trench extends for from a triple junction in the west with the Ulakh ...

to its south. What remained of the Kula Plate attached to the North American Plate. This former subduction zone is now the Beringian Margin, which now hosts sixteen submarine canyons, including

Zhemchug Canyon Zhemchug Canyon is an underwater canyon located in the middle of the Bering Sea. It is the deepest submarine canyon in the world, and is also tied for the widest.Normark, W.R. and Carlson, P.R., 2003Giant submarine canyons: Is size any clue to ...

, the world's largest. The deep-water part of the Bering Sea is separated into the

Commander Basin The Commander Basin (alternately Komandorsky Basin) is located between the Shirshov Ridge and the Kamchatka Peninsula. Its southern boundary is the Aleutian arc (see figure) and occupies the western part of the Bering Sea. The Kamchatka Strait pr ...

and Bowers basins by the submarine

Shirshov Ridge The Shirshov Ridge is located on the eastern border of the Commander Basin below the Kamchatka Peninsula. It extends directly southward for a distance of 750 km toward the Aleutian arc in the eastern part of the Bering Sea (see figure).E. V. ...

and

Bowers Ridge The Bowers Ridge is located in the southern part of the Aleutian Basin. It extends over in an arc, starting in the southeast at the Aleutian Arc and terminating to the northwest at the Shirshov Ridge. The Bowers Ridge arc separates the Aleutian ...

. The

occupies the western part of the Bering Sea, with the Shirshov Ridge on its eastern border. The Shirshov Ridge extends 750 km southward from the Russian

Olyutorskii Peninsula Olyutorsky District (russian: Олю́торский райо́н) is an administrativeLaw #46 and municipalLaw #339-oz district (raion) of Koryak Okrug of Kamchatka Krai, Russia, one of the eleven in the krai. It is located in the northeast of the ...

to connect with Bowers Ridge. The Bowers Ridge extends in the form of an arc over approximately 900 km from the

Aleutian Islands The Aleutian Islands ( ; ; ale, Unangam Tanangin, "land of the Aleuts"; possibly from the Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before 1867, the Catherine Archipelago—are a chain of 14 main, ...

Arc to the northwestern termination, where it meets Shirshov Ridge. This former

island arc Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle alo ...

, Bowers Ridge, is a prominent semi-circular-shaped geological that meets the Aleutian arc and, together with the Aleutians, bounds

Bowers Basin Bowers may refer to: Persons *Bowers (surname) Places ;Antarctica * Bowers Mountains * Bowers Piedmont Glacier ;United Kingdom * Bowers, Staffordshire, England * Bowers Gifford, Essex, England ;United States * Bowers, Delaware * Bowers, Indi ...

The northern part of the Shirshov Ridge formed 95 My before the present. The ridge grows younger as it goes south, with the southern part of the Shirshov Ridge formed 33 My ago (Early Oligocene). Bowers Ridge was formed 30 My before the present (Late Oligocene).

References

{{coord, 57, N, 177, E, type:landmark_region:XP_dim:3000000, display=title Oceanic basins of the Pacific Ocean Landforms of the Bering Sea