There are very many different things that can cause volcanoes to explode.when the volcanologist made her observations she noticed that there weren't a lot of volcanoes on our plate but the ones that were on our plate were on the edges of our plate and not many in the middle.If you look in this picture it will show where each of the volcanoes erupted and were they erupted. when the team was doing research one of the books said that most volcanoes form along the mid-ocean ridge which then divides the plate boundaries, as you can see here on this picture.Another thing that we found out was that along the ridge,lava pours out of cracks in the ocean floor.some other things that we researched was that a hot spot is an area where magma from deep within the mantle metals through the crust like a blow torch.
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