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Do-it-yourself lava flows

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Elise Andrew

CEO and Founder

clockOct 22 2013, 15:58 UTC
25 Do-it-yourself lava flows
Jeffrey A. Karson

Yep, that’s a man-made lava flow being poured down that funnel, as part of the Syracuse University Lava Project; a collaboration between sculptor Bob Wysocki (Assistant Professor, Department of Art) and geologist Jeff Karson (Professor, Department of Earth Sciences). 1.1-billion-year-old basalt from Wisconsin is melted and poured to produce natural-scale lava flows up to a few meters long; sometimes the lava is poured into molds and onto a variety of surfaces by sculpture students. The lava pours are also used for classes, student groups and the public; bringing the excitement of a volcanic eruption to Central New York. Various questions from onlookers are often answered by experiment: ‘what would happen if you threw apples into lava’ resulted in the crowd watching as apples were engulfed by the lava. Marshmallows have been known to be toasted and hot dogs cooked over the newly formed lava.

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The lava used in the experiments is commercially available and originates from lava flows from the Mid-Continent rift in northwestern Wisconsin, similar to flows found in the East African Rift, Iceland or Hawaii. The crushed basalt is loaded into a natural gas-fueled tilt furnace, heated to 1,100 to 1,350°C. The crucible can hold up to 360kg of molten basalt; this lava is heated for several hours until it becomes a homogeneous, convecting magma. The flow rate is controlled manually by tilting the crucible and channeling the lava through a steel chute with a diameter of 20cm.The lava can be ‘recycled’ for further experiments. So far, the team have completed more than 50 lava flow experiments with more than 100 individual flows.

Basaltic lava flows are the most common and largest volcanic flows on Earth and the terrestrial planets; Hawaii, Iceland and Italy in particular are known for their frequent basaltic eruptions. The Large Igneous Provinces in the oceans and on the continents are also predominantly composed of basalt. While basalt flows can be studied in the field, they tend to be inaccessible and erupt without much warning (as well as being somewhat dangerous). Therefore these experiments by the Syracuse University Lava Project assist with understanding the behavior of these lava flows, including composition (especially silica content), dissolved volatiles and crystallinity, temperature, flow rate, slope and what material the lava flows over. To eliminate composition as a variable, the team uses a single type of basalt in their experiments, though they hope in the future to use more silica-rich basaltic andesites (typical of subduction zones); very magnesium-rich komatiite (similar to lavas that erupted early in Earth’s history); and carbonatites (exotic carbonate lavas).

Tiny 1mm needle-like plagioclase feldspar crystals have been seen to form in well-insulated pockets of about 10-centimeter thick, low-temperature (around 1,100°C) flows, though it is not clear whether the crystals formed during active flows or subsequent cooling. 

The team have experimented with lava flows on a variety of surfaces, and vary the features by changing the slope and texture of the surfaces they use. They have used dry sand, moist and wet sand, and water surfaces. Their investigations into how lava interacts with ice revealed that highly vesicular flows develop and bubbles cool rapidly, resulting in flexible and transparently thin walls (see the right-hand photo). To investigate how lava would interact in contact with glaciers on Earth and on other planets, the team poured the lava onto a horizontal carbon dioxide-ice surface; this demonstrated a hydroplaning effect in which lava rapidly splashed off the surface.

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All of the experiments are recorded and some are posted to the web here


Nature
  • lava,

  • geology,

  • volcano