How volcanoes form
Description: A volcano
Image copyright: http://interactive2.usgs.gov/learningweb/images/volcanoes_intro14_sm.jpg
Volcanoes form when two plates crash together .One of the plates slides under another plate this process is called subduction .Volcanoes form when hot material from below rises and leaks into the crust. This hot material is called magma .Extreme pressure forces magma through the weak spots in the earths crust .Then the magma breaks the crust making volcanoes .The lava erupts and the magma and ashes fly everywhere . Some magma comes up and hardens .The lava does this over and over making the volcano really big!
Bibliography
National Geographic volcanoes .published in 1995 Dec.12-20-07. http://www.nationalgeographic.com/forcesofnature/interactive/index.html?section=v
Windows to the universe volcanoes. Published in 1995. dec.12-20-07. http://www.windows.ucar.edu/tour/link=/earth/interior/volcanos_general.html
National Geographic kids volcanoes. published in 1996.12-20-07. http://www.nationalgeographic.com/ngkids/0312/main.html