Published on December 14th, 2010 | by Joshua S Hill
Hawaii Sitting Shallow Atop Magma
An Ohio State University honours undergraduate student has found that the Hawaiian Island volcani chain sits atop a single magma chamber which is much closer to the surface than was originally supposed.
“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,” explained Julie Ditkof, an honors undergraduate student in earth sciences at Ohio State. “Now we know the chamber is at a shallow depth not seen anywhere else in the world.”
Ditkof took a technique that her advisor Michael Barton – a professor of earth sciences at Ohio State University – had originally developed and applied to magma in Iceland, and used it to understand the Hawaiian Island volcanic chain. She found that the magma lies at an average of 3 to 4 kilometres (about 1.9 to 2.5 miles) beneath the surface of Hawaii. In comparison, Barton found that the magma chambers that lie beneath Iceland are on average 20 kilometres below the surface.
Ditkof also explains, however, that Hawaiians have nothing to fear from this new revelation. “The crust in Hawaii has been solidifying from eruptions for more than 300,000 years now. The crust doesn’t get consumed by the magma chamber. It floats on top.”
These revelations could not only help scientists predict when Hawaiian volcanoes may erupt, but also point towards the possibility of a greater potential for thermal energy in the region. “Hawaii has huge geothermal resources that haven’t been tapped fully,” he said, and quickly added that scientists would have to determine whether tapping that energy was practical – or safe. “You’d have to drill some test bore holes. That’s dangerous on an active volcano, because then the lava could flow down and wipe out your drilling rig.”