Romanche Trench

The Romanchegraben, also Romancherinne or Romanche depth is an approximately 965 km long and 19 km wide, deep groove in the center of the Atlantic Ocean ( Atlantic) with a maximum depth of 7,730 m.

Geography

The Romanchegraben located between the Sierra Leone Basin in the north and north-east, the South Atlantic ridge in the east and southeast, the northern Brazilian basins in the south and south west and the North Atlantic Ridge to the west and northwest. There he lies on the equator as the interface of the North and South Atlantic Ridge, the two halves of the Mid-Atlantic Ridge, between each about 2 ° north and south latitude and 16 ° and 20 ° west longitude.

Geology

The Romanchegraben is a large transform fault that the Mid-Atlantic Ridge, the interface of South American plate to the west and the east African plate, offset by several hundred kilometers. The movement on the fault is on average 1.7 cm per year. The Mid-Atlantic Ridge dissolves in approximation to the transform fault into several staggered sections and is indistinct, eventually disappearing 30 km in front of her. In contrast to the otherwise normal, consisting of basaltic oceanic crust is assumed that the ocean floor consists of serpentinized peridotite around the trench.

Oceanic circulation

The Romanchegraben is an interruption of the Mid-Atlantic Ridge of importance for the spread of ground water in the area of the Atlantic. Because of the way north is blocked by the Walvis Ridge off Namibia, can for the first time formed in the Antarctic cold Antarctic bottom water with its temperature of around 1.5 ° C in a flow rate of 3.6 Sverdrup ( 3.6 × 106 m³ / s ) flow into the eastern part of the Atlantic.

History

The Romanchegraben was discovered in 1883 by a French expedition, named it after their ship. The researchers were on the way back from Tierra del Fuego, where they had taken in the First International Polar Year 1882/83, a weather station and a geomagnetic observatory operated in Orange Bay and the transit of Venus from the December 6, 1882 observed.