Atlantic sea floor. Hemispherical artwork of the sea floor topography of the Atlantic Ocean,showing the Mid-Atlantic Ridge,continental shelves and underwater mountains. On land,features shown include the Greenland ice cap,Arctic tundra,vegetated areas,and rivers,lakes,seas,mountains,and deserts. The Mid-Atlantic Ridge is a divergent tectonic plate boundary,with new sea floor being created between the North American Plate (left) and the Eurasian Plate (right). 16,000 kilometres long,it joins to other mid-ocean ridges to form the longest mountain range in the world |