How Volcanoes Work

 Image Described in Caption
 Skylight -- incandescent molten lava exposed through skylight on Kilauea volcano, Hawaii. The lava tube is associated with the Kupaianaha eruption from the east rift zone of Kilauea in 1989. The steam plume in background marks the terminus of the lava tube at its outlet to the ocean. Courtesy of the USGS.