Question

iceland was formed by what plate tectonic action

Answer 1

Flow of magma at the Mid-Atlantic-Ridge does not build up islands in the several thousands of meters deep ocean. The existence of Iceland points to another important fact: A so called hot-spot, the Iceland plume, is located near the Mid-Atlantic-Ridge in the North Atlantic and it is believed to have caused the formation of Iceland itself. A hot-spot (also “mantle plume”) is an upwelling of abnormally hot rock within the Earth's mantle.
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