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A college student who pinpointed the depth of Kilauea Volcano’s magma chamber says the finding could lead to better predictions of eruptions.
"Hawaii was already unique among volcanic systems, because it has such an extensive plumbing system, and the magma that erupts has a unique and variable chemical composition," says Ohio State University undergraduate Julie Ditkof. "Now we know the chamber is at a shallow depth not seen anywhere else in the world."
For her honors thesis, Ditkof took a technique that her adviser, Michael Barton, professor of earth sciences at Ohio State, developed to study magma in Iceland, and applied it to Hawaii.
She discovered that magma lies an average depth of 1.9 to 2.5 miles (3 to 4 kilometers) below the surface.
Ditkof was due to present her findings tomorrow at a meeting of the American Geophysical Union in San Francisco.
By comparison, Barton determined that magma chambers beneath Iceland lie at an average depth of 12 miles (20 kilometers).
Barton and Ditkof determined that one large magma chamber feeds Kilauea, Mauna Loa and Loihi volcanoes through different conduits.
They came to this conclusion after Ditkof analyzed the chemical composition of nearly 1,000 magma samples. From the ratio of some elements to others — aluminum to calcium, for example, or calcium to magnesium — she was able to calculate the pressure at which the magma had crystallized.
For his studies of Iceland, Barton created a way to convert those pressure calculations to depth.
Ditkof says researchers could use this technique to regularly monitor pressures inside the chamber and make more precise estimates of when eruptions are going to occur.
In a news release, Barton said that the finding ultimately might be more important in terms of energy.
"Hawaii has huge geothermal resources that haven’t been tapped fully," he said, adding that scientists would have to determine whether tapping that energy on a large scale is practical or safe.
