An ocean bank, sometimes referred to as a fishing bank or simply bank, is a part of the seabed that is shallow compared to its surrounding area, such as a shoal or the top of an underwater hill. Somewhat like continental slopes, ocean bank slopes can

upwell __NOTOC__ Upwell is a village and civil parish in the English county of Norfolk. Upwell village is on the A1101 road, as is Outwell, its conjoined village at the north. The nearest towns are Wisbech to the north-west and Downham Market to th ...

as tidal and other flows intercept them, sometimes resulting in nutrient-rich currents. Because of this, some large banks, such as Dogger Bank and the Grand Banks of Newfoundland, are among the richest fishing grounds in the world. There are some banks that were reported in the 19th century by navigators, such as

Wachusett Reef Wachusett Reef was a phantom reef in the Antarctic Ocean. Captain Lambert of the ship ''Wachusett'' reported that on June 4, 1899 he passed over a reef which appeared to be of coral Corals are marine invertebrates within the class Anthoz ...

, whose existence is doubtful.

Types

Ocean banks may be of volcanic nature. Banks may be

carbonate A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...

terrigenous In oceanography, terrigenous sediments are those derived from the erosion of rocks on land; that is, they are derived from ''terrestrial'' (as opposed to marine) environments. Consisting of sand, mud, and silt carried to sea by rivers, their com ...

. In tropical areas some banks are submerged

atoll An atoll () is a ring-shaped island, including a coral rim that encircles a lagoon partially or completely. There may be coral islands or cays on the rim. Atolls are located in warm tropical or subtropical oceans and seas where corals can gro ...

s. As they are not associated with any

landmass A landmass, or land mass, is a large region or area of land. The term is often used to refer to lands surrounded by an ocean or sea, such as a continent or a large island. In the field of geology, a landmass is a defined section of contine ...

, banks have no outside source of sediments. Carbonate banks are typically platforms, rising from the ocean depths, whereas terrigenous banks are elevated sedimentary deposits.

Seamount A seamount is a large geologic landform that rises from the ocean floor that does not reach to the water's surface (sea level), and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abr ...

s, by contrast, are mountains rising from the deep sea and are steeper and higher in comparison to the surrounding seabed.Farallones Marine Sanctuary Association
Islands, Banks & Seamounts: Geologic Features Under the Sea
. Examples of these are Pioneer and Guide Seamounts, west of the

Farallon Islands The Farallon Islands, or Farallones (from the Spanish ''farallón'' meaning "pillar" or "sea cliff"), are a group of islands and sea stacks in the Gulf of the Farallones, off the coast of San Francisco, California, United States. The islan ...

. The Pioneer Seamount has a depth of 1,000 meters, In other cases, parts of a bank may reach above the water surface, thereby forming islands.

Important banks

The largest banks in the world are: # Grand Banks of Newfoundland (280,000 km²) - terrigenous bank #

Agulhas Bank The Agulhas Bank (, from Portuguese for Cape Agulhas, ''Cabo das Agulhas'', "Cape of Needles") is a broad, shallow part of the southern African continental shelf which extends up to south of Cape Agulhas before falling steeply to the abyssal p ...

(116,000 km²) # Great Bahama Bank (95,798.12 km², has islands, area without islands) # Saya de Malha (35,000 km², excluding the separate North bank, least depth 7 m) # Seychelles Bank (31,000 km², including islands of 266 km²) # Georges Bank (28,800 km²) - terrigenous bank # Lansdowne Bank (4,300 km²,Le parc naturel de la mer de Corail
p. 26 west of New Caledonia, least depth 3.7 m) # Dogger Bank (17,600 km², least depth 13 m) # Little Bahama Bank (14,260.64 km², has islands, area without islands) # Great Chagos Bank (12,642 km², including islands of 4.5 km²) # Reed Bank, Spratly Islands (8,866 km², least depth 9 m) # Caicos Bank,

Caicos Islands The Turks and Caicos Islands (abbreviated TCI; and ) are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of tropical islands in the Lucayan Archipelago of the Atlantic Ocean and nor ...

(7,680 km², including islands of 589.5 km²) #

Macclesfield Bank Macclesfield Bank is an elongated sunken atoll of underwater reefs and shoals in the South China Sea. It lies east of the Paracel Islands, southwest of Pratas Island and north of the Spratly Islands. It is about long from southwest to northeas ...

(6,448 km², least depth 9.2 m) # North Bank or Ritchie Bank (5,800 km², north of Saya de Malha, least depth <10 m) #

Cay Sal Bank Cay Sal Bank ( es, Placer de los Roques) is the third largest (after Great Bahama Bank and Little Bahama Bank) and the westernmost of the Bahama Banks. It is located between 23º27'N - 24º10'N and 079º25'W – 080º35'W. In a geographical sens ...

(5,226.73 km², including islands of 14.87 km²) #

Rosalind Bank Rosalind Bank, also called Rosalinda or Rosa Linda Bank ( es, Placer de Rosalinda), is a large, completely submerged bank or atoll in the western Caribbean Sea. It is the culmination of an area of coral reef, some 300 km (186 mi) long, that extend ...

(4,500 km², least depth 7.3 m) # Bassas de Pedro (2,474.33 km², least depth 16.4 m), part of the

Amindivi The Aminidivi Islands, are one of the three island subgroups in the Union Territory of Lakshadweep, India. It is the northern group of the Lakshadweep, separated from the Laccadive Islands subgroup roughly by the 11th parallel north. The total ...

Subgroup of Lakshadweep, India

Notes

External links

Definitions – Islands, Banks & Seamounts: Geologic Features Under the Sea
{{fishing by country Physical oceanography

Types

Important banks

See also

Notes

External links