What is the connection between convection and volcanoes ?

Question

What is the connection between convection and volcanoes ?

Answer 1

While the vast majority of volcanoes occur at tectonic plate boundaries and can be explained as the result of those boundary conditions, there are also volcano's which occur far from plate boundaries.  The current widely accepted explanation for these mid-plate volcanoes is that they occur at "hot spots" - where convective currents in the upper mantle bring heat to the surface at point locations causing vulcanism at the crust.  The best example of this is the Hawaiian Island chain which has been produced by a series of volcanoes as the Pacific Plate moves in a northwesterly direction over one such hot spot.  The youngest island (the big island Hawaii) is at the southeastern most end of the chain and as you move to the northwest the islands become progressively older.  There is even an undersea volcano (called a sea mount) to the southeast of the big island which will one day break the surface and become the newest addition to the Hawaiian Island chain.