Researchers are studying how lava changes when it flows on, under and next to snow and ice. The different patterns can be used to hunt for now-disappeared glaciers from past ice ages.
Lava and ice at Veniaminof volcano in Alaska, Aug. 2013.
Tuya Butte, the volcano in northern British Columbia that is the source of the term tuya — a volcano that erupted under ice.
Lava flows at Canada's Hoodoo Mountains dammed behind a glacier, now disappeared.
Hayrick Butte in northern Oregon is an example of a tuya in the United States.
At Syracuse University in New York, scientists are simulating their own lava-ice interactions.
Tunnel of lava
Imagine a lava flow creeping slowly through a circular tunnel melted into the ice. Cool down the lava flow, then remove the ice. The sinuous shape of the lava flow shows that it was confined by ice.
A table mountain in Iceland, the local term for a volcano that erupted under ice.
Antarctica's fiery past
View across northwestern James Ross Island, a subglacially-erupted volcano in Antarctica.
Close-up of the glassy lava breccia called hyaloclastite formed when lava flows into water and explodes into fragments.
Where water once flowed
A lava-fed delta on James Ross Island in Antarctica. The horizontal surface separating the layers marks the former water level.
Becky Oskin, Contributing Writer
Becky Oskin covers Earth science, climate change and space, as well as general science topics. Becky was a science reporter at Live Science and The Pasadena Star-News; she has freelanced for New Scientist and the American Institute of Physics. She earned a master's degree in geology from Caltech, a bachelor's degree from Washington State University, and a graduate certificate in science writing from the University of California, Santa Cruz.