The study of the relief of the bottom of the Atlantic Ocean began in the middle of the twentieth century. The average depth is 3736 meters, and the greatest is 8742 meters. In the structure of the ocean, there are three main parts:
- Mid-Atlantic Ridge;
- Continental margins;
That is, the topography of the ocean floor is quite diverse and in no case can it be attributed to the flat topography.
The total length of the ridges of the Arctic to the Antarctic sea is about 40 thousand kilometers.
Features of the bottom topography
Of all the features of the ocean relief, the main one can be distinguished this is the Mid-Atlantic Ridge. It goes through the whole ocean. The relative height of the ridge is about two meters. Transverse faults divide it into separate segments, and in the axial part of the ridge there is a giant rift valley with a width of 6 to 30 kilometers and a depth of up to 2 kilometers. Earthquakes and volcanic eruptions also occur here. Along the ridge there is a rift system, where the largest volcanic island, Iceland, was formed. There are 140 volcanoes on this island and 26 of them are active. The most famous volcano of them is Hekla. On both sides of the ridge lie hollows with a relatively flat bottom, which are separated by elevated uplifts. The shelf area in the Atlantic Ocean is larger than in the Pacific. The median ridge stretches in the meridional direction and divides the ocean into western and eastern parts.
In the rift zones, mineral springs were also found with a temperature of metal salt solutions of about 4000 degrees Celsius, metal salts are deposited in ocean water in the form of black deposits that form something in the form of a tall pipe. They were also called black smokers.
Unlike the Pacific Ocean, the Atlantic has little deep-sea trenches. The deepest of them is Puerto Rico. Its depth is 8742 meters in the Caribbean Sea. And within the ocean there is a well-defined shelf zone. This is especially well observed in the Northern Hemisphere off the coast of North America and Europe.
Bottom relief characteristics
Also, the Atlantic Ocean has transition zones. They are represented by the following areas:
The Caribbean region includes: the Caribbean Sea, the deep-water part of the Gulf of Mexico, island arcs and deep-sea trenches. In this area, the following arcs can be distinguished: Cuban, Jamaica Southern Haiti, Cayman Sierra Maestra, even the outer and inner Lesser Antilles. In addition, the underwater height of Nicaragua and the ridges of Beata and Aves are distinguished here. The Cuban arc has a rather complex structure and has a Laramian age of folding. Its continuation is the northern cordillera of the island of Haiti. The Cayman-Siera Maestra fold structure, which is of Miocene age, begins with the Maya mountains in the Yucatán Peninsula, then continues in the form of the Cayman submarine ridge and the Sierra Maestra mountain range of South Cuba. And the Little Antilles arc includes a number of volcanic formations. Island arcs and underwater ridges divide the bottom of the Caribbean Sea into several basins. The deepest of them is the Venezuelan (5420 meters). There are also two deep-sea trenches here Cayman and Puerto Rico, which has the deepest depth of the Atlantic Ocean.
The areas of the Scotia Ridge and the South Sandwich Islands are borderlands sections of the underwater continental margin, fragmented by tectonic movements of the earth’s crust. The island arc of the South Sandwich Islands is filled with a series of volcanoes.
In the Mediterranean Sea, there is a wide distribution of the continental crust. The suboceanic crust is developed only in spots in the deepest basins
Also, as already known earlier, there are a lot of ridges in the Atlantic Ocean. In addition to the Mid-Atlantic, there is the South Atlantic Ridge, which has a meridional strike. The number of transverse faults on it is less, so the ridge looks monolithic. In the southern and middle parts of the ridge, the volcanic plateaus of the Ascension, the islands of Tristan da Cunha, Gough, Bouvet stand out. From Bouvet Island, the South Atlantic Ridge turns east, goes around Africa and merges with the West Indian Mid-Range in the Indian Ocean.
Large islands in the Atlantic Ocean: South Greenland, Iceland, Cuba, Haiti, Newfoundland.
Deep sea trenches: Puerto Rico, Cayman, Romansh, South Sandwich.