What happens when molten rock meets a block of ice? At Syracuse University in New York, a geologist and a sculptor found out by melting real basalt and pouring it straight onto ice. The glowing lava skated across the surface on a cushion of steam and slipped into cracks beneath it, and the results ended up in the journal Geology.
The Syracuse University Lava Project
The Lava Project was founded by two people from very different departments: Bob Wysocki, a sculptor and assistant professor in the Department of Art, and Jeff Karson, a geologist and professor of Earth Sciences. Wysocki melts rock in modified furnaces originally designed for working with metal, producing lava similar to seafloor basalt and to the lava that erupts in Hawaii and Iceland.
The team then pours the melt over all kinds of surfaces to see how it behaves: steel sheets and troughs, dry and wet sand, gravel, clay, snow, ice, dry ice and water. Infrared cameras record surface temperatures, thermocouples are pushed into the flows, and video, stereo cameras and a drone document every pour. The project also stages public pours for students and visitors at the university's Comstock Art Building.
What happens when lava meets ice
In the ice experiments, more than 300 kg of basalt was melted and poured over densely packed ice. Instead of simply melting straight through, the lava raced across the top at tens of centimetres per second. A thin layer of steam formed where the hot rock touched the ice and acted like a lubricant, letting the flow glide over the surface.
That steam layer also works as insulation. The researchers proposed that it slows the transfer of heat from lava to ice, so the ice melts more slowly than you might expect. Other effects showed up too:
- Flow beneath the ice: where the ice had cracks or weak spots, lava found them and moved under and inside the block.
- Bubbles: meltwater and steam bubbled up through the lava, forming thin lava bubbles known as "Limu o Pele" and larger gas cavities.
- Ash as a shield: a layer of sand on the ice, standing in for volcanic ash, greatly slowed melting when lava later flowed over it.
Why lava–ice experiments matter: volcanoes under ice
The study, led by Benjamin Edwards of Dickinson College with Karson, Wysocki and colleagues, was published in Geology in 2013 under the title "Insights on Lava-Ice/Snow Interactions from Large-Scale Basaltic Melt Experiments". It matters because more than 200 volcanoes worldwide are currently covered by ice and snow. When they erupt, the meeting of lava and ice can cause floods, explosions and damage to nearby communities, yet these eruptions are remote and hard to watch up close.
The lab results matched what geologists had seen in eruptions in Iceland and on Sicily, where lava found weaknesses in the ice, tunnelled beneath it and flowed on through existing fractures. The authors also suggested new ways to recognise lava flows that formed in contact with ice, both on Earth and on Mars, which helps scientists reconstruct past climates.
Explore more: Tolbachik photographed in a natural volcanic setting; another experiment involving water and phase change. The project's page on Syracuse Lava Project experimental variables lists every surface the team has tested.
Related reading
- The May 2013 Ice Shoves at Mille Lacs and Dauphin Lake
- Iain Stewart Explores Ice in Earth: The Power of the Planet
- An Ice Lens and the Concentration of Sunlight
- Roof Ice Falling at a Lodge in Grapevine, Texas
- Ten Snow, Ice and Water Landscapes: Glaciers, Mountains and Frozen Shores
Sources
- Syracuse University Lava Project and its instrumentation page
- Edwards et al. (2013), Geology 41(8): 851–854
- Smithsonian Magazine: Song of Fire and Ice
- Video and still: Lava Poured on Ice, Syracuse University Lava Project
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