dwarf acacias, and swallowworts may be found. Some high grass, mixed with balsam, spurge, and spiny shrubs, grows in the central region. The north has little vegetation. Climate The Coastal Zone, or Sub-Canarian Zone, extends the length of the approximately 754-kilometer-long Atlantic coast. Prevailing oceanic trade winds from the Canary Islands modify the influence of the harmattan, producing a humid but temperate climate. Rainfall here is minimal; in Nouadhibou it averages less than three centimeters annually and occurs between July and September. Temperatures are moderate, varying from mean maxima of 28 °C and 32 °C for Nouadhibou and Nouakchott, respectively, to mean minima of 16 °C and 19 °C. Geology The depositional profile of the northern Banc d'Arguin describes a flat-topped platform, on which extensive carbonate deposits developed largely in water depths <10 meters below sea level. Vast areas of the Banc d'Arguin are covered by mixed carbonate–siliciclastic sediments dominated by barnacles and mollusk remains plus admixed eolian siliciclastics. These sediments accumulate into extensive shoals, occasionally causing water depths below 5 m several dozens kilometers offshore the present shoreline. The bank edge forms a sharp morphological step, suddenly deepening from 10–20m down to 30–50m, and separates the inner shelf environments (<5–10m; carbonate bank) from those of the outer shelf. Assemblages formed by benthic foraminifers and mollusks and monospecific bivalve shell accumulations with admixed eolian silt characterize the platform cover in the outer shelf. In the central and southern outermost shelf, silt-sized quartzose materials form confined bodies referred to as the Arguin and Timiris Mud Wedges. These deposits started to form with transgressional inundation early in the Holocene and have grown continuously and rapidly over the past 9 kyrs. Locally, the mud wedge deposits are incised by gullies and canyons towards the shelf break lying at around 80–110m. The southernmost Golfe d'Arguin describes a homoclinal ramp profile with vast intertidal plains around Tidra Island. History Because of its rich fishery and strategic location, the territory has been highly coveted and disputed by the European colonial powers of Portugal, France, England, Brandenberg/Prussia and Holland. The Wreck of Medusa – La Méduse was a French frigate that ran aground at high tide off Banc d'Arguin on 2 July 1816.A scene inspired by the account of survivors Alexandre Corréard and Jean-Baptiste-Henri Savigny was made the subject of a painting in 1819 by Théodore Géricault called "The Raft of the Medusa", which is displayed in