Where did volcanoes come from?
Jana
Bulger
Hi Jana,
Volcanoes form when magma (molten rock) from within the Earth erupts to the
surface. If you have lots of eruptions from the same place, eventually a large
volcano will build up. Some volcanoes only erupt once and never again.
They tend to be the small ones. Volcanoes are continually being born, so there
will be new ones coming along all the time.
If you look at a map of volcanoes you will notice that they do not occur all
over the Earth, but instead, in rather definite areas. This is because magma
does not reach the surface at just any old place.
Sincerely,
Scott Rowland, University of Hawaii