Gulf of Cadiz

The Gulf of Cádiz (Spanish: Golfo de Cádiz, Portuguese: Golfo de Cádis) is the arm of the Atlantic Ocean between Cabo de Santa Maria, the southernmost point of Mainland Portugal and Cape Trafalgar at the western end of the Strait of Gibraltar. Two major rivers, the Guadalquivir and the Guadiana, as well as smaller rivers, like the Odiel, the Tinto, and the Guadalete, reach the ocean here.

The Gulf of Cádiz is located in the north-eastern Atlantic Ocean between 34°N and 37°15′N and 6°W to 9°45′W. It is enclosed by the southern Iberian and northern Moroccan margins, west of Gibraltar Strait.

The geological history of the Gulf of Cádiz is intimately related to plate tectonic interaction between Southern Eurasia and North Africa and is driven by two major mechanisms:

It is now well established that the whole area is under compressive deformation and that mud volcanism and processes associated with the escape of hydrocarbon-rich fluids sustain a broad diversity of chemosynthetic assemblages. The accretionary wedge formed by subduction represents an extensive area which encompasses over forty mud volcanoes (a type of cold seep), at depths ranging from 200 to 4,000 m (660 to 13,120 ft) (confirmed by coring), and active methane seepage has been documented on several locations.

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