Southeastern United States continental shelf

Coast and Geodetic Survey steamer BLAKE Washington Navy Yard

The Blake Plateau lies in the western

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

off the southeastern United States coasts of

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia a ...

South Carolina )'' Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no) , anthem = "Carolina";" South Carolina On My Mind" , Former = Province of South Carolina , seat = Columbia , LargestCity = Charleston , LargestMetro = G ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to t ...

and

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, a ...

. The Blake Plateau lies between the North American continental shelf and the deep ocean basin extending about east and west by north and south, with a depth of about inshore sloping to about about off shore, where the Blake Escarpment drops steeply to the deep basin. The Blake Plateau, associated Blake Ridge and

Blake Basin The Blake Basin, also called the Blake–Bahama Basin, is a deep area of the Atlantic Ocean which runs along the east coast of the United States. It starts at the northern part of the Bahamas and continues up toward New York. The depth exceeds 5400 ...

are named for the

U.S. Coast and Geodetic Survey The National Geodetic Survey (NGS) is a United States federal agency that defines and manages a national coordinate system, providing the foundation for transportation and communication; mapping and charting; and a large number of applications ...

steamer , in service 1874–1905, that first used steel cable for oceanographic operations and pioneered deep ocean an
Gulf Stream
exploration. Survey lines of the steamer ''George S. Blake'' first defined the plateau that now bears the ship's name.

History

In July 1880 ''George S. Blake'' under the command of Commander John R. Bartlett, U.S.N., was working with sounding gear designed by Lieutenant Commander Sigsbee in cooperation with

Alexander Agassiz Alexander Emmanuel Rodolphe Agassiz (December 17, 1835March 27, 1910), son of Louis Agassiz and stepson of Elizabeth Cabot Agassiz, was an American scientist and engineer. Biography Agassiz was born in Neuchâtel, Switzerland and immigrated to ...

collecting biological samples and examining the

Gulf Stream The Gulf Stream, together with its northern extension the North Atlantic Drift, is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and flows through the Straits of Florida and up the eastern coastline of the Uni ...

running eastward fro
Cape Romain
when, in taking frequent soundings eastward, "depths on this line were unexpectedly small, the axis of the Gulf Stream being crossed before a depth of three hundred fathoms ( was found" with a bottom of "hard coral" and little life. This was early indication of the plateau that would in the future carry the ship's name. In 1882 Commander Bartlett described the plateau: Bartlett reported the scouring effect of the current on the plateau, noting that on each side of the current the sounding cylinder, a device for sampling the nature of the bottom with the sounding, brought up ooze. Within the current the "bottom was washed nearly bare", with particles being small and broken pieces of coral rock and so hard the sharp edge of the brass cylinder was bent.

Characteristics

Geology

Due to unusual features of the plateau, particularly scouring by th

and th

that merge over the plateau to form the Gulf Stream, mineral deposits, particularly

manganese nodule Polymetallic nodules, also called manganese nodules, are mineral concretions on the sea bottom formed of concentric layers of iron and manganese hydroxides around a core. As nodules can be found in vast quantities, and contain valuable metals, ...

s, have long been of interest. Methane and other gas hydrates are also found on the plateau.

Biology

The Blake Plateau, although described as a "bleak, current-swept plain," has biological communities including ''

Lophelia pertusa ''Lophelia pertusa'', the only species in the genus ''Lophelia'', is a cold-water coral that grows in the deep waters throughout the North Atlantic ocean, as well as parts of the Caribbean Sea and Alboran Sea. Although ''L. pertusa'' reefs are ...

'' reefs that support communities as well as communities supported by gas hydrates. Commercial fishermen have begun exploiting deep sea fish on the plateau with studies being undertaken on the viability as these fish, although large, grow slowly. Biological sampling of the deep, hard bottom is difficult under the Gulf Stream with the consequence that the fauna is relatively poorly known. (See "Blake Plateau")

Notes

References

External links

{{DEFAULTSORT:Blake Plateau) Plateaus of the Atlantic Ocean Marine geology