P4+Volcanoes

=Volcanoes= A volcano is a opening in the surface, or the crust which allows magma and hot gases to come out. Volcanoes can be usually found were tectonic plates are moving,volcanos are not usually created by two tectonic plates sliding across from eachother.Volcanoes can sometimes be caused by Mantle Plumes, Which are the upwelling of very hot rocks in the earths mantle. The most active volcaneo in the USA is Mount Saint Helens, which is famous for it's eruption in the 1980's.The largest volcano in the Solar System is Olympus Mons, which is located on Mars.