Photograph by Gordon Tribble and courtesy of U.S. Geological Survey.
Eruptions under water or ice produce pillow lava. James Moore of the U.S. Geological Survey made the first underwater
observations of the formation of pillow lavas (Moore and others, 1973). Moore and his coworkers studied lava from the Mauna Ulu eruption. They described pillow lavas as elongate,
interconnected flow lobes that are elliptical or circular in cross-section (Moore, 1975). This photo shows pillow lava
forming off the south coast of Kilauea volcano, Hawaii.
Pillow lava. Photograph courtesy of U.S. Geological Survey.