Iceland has the unique position of being the largest subaerial part of the mid-oceanic ridge system worldwide. Ridges south and north of Iceland, Reykjanes Ridge and Kolbeinsey Ridge is much more shallow bathymetry when compared to mid-oceanic ridge. Mid-Atlantic Ridge has a hotspot with an area of excessive mantle upwelling. The hotspot – ridge interaction has been a major factor in the morphological and geological evolution of the North Atlantic. The mid-ocean ridge system is the most extensive chain of mountains on earth, more than 90% of this mountain range lies in the deep ocean. The average depth to the crest (top) of the ridge is 2500 m and it rises above sea-level in Iceland. Since most of the mid-ocean ridge is more than 2000 meters deep, most of its eruptions go unnoticed.
http://www.un.org/Depts/los/clcs_new/submissions_files/isl27_09/isl2009executivesummary.pdf
http://oceanexplorer.noaa.gov/explorations/05galapagos/background/mid_ocean_ridge/mid_ocean_ridge.html
http://www.un.org/Depts/los/clcs_new/submissions_files/isl27_09/isl2009executivesummary.pdf
http://oceanexplorer.noaa.gov/explorations/05galapagos/background/mid_ocean_ridge/mid_ocean_ridge.html