One of the most productive global areas for gaining access to geothermal energy sources is the "Ring of Fire", a result of shifting of tectonic plates that form a boundary between the Pacific Ocean and the land masses surrounding it. Along that boundary, magma from the earth's interior rises to where it is close enough to the surface to allow access to the heat it carries. Both volcanoes and earthquakes can result, but the same heat can also be accessed by drilling and tapping into the earth.