YELLOWSTONE - The underground plume that feeds the world's largest super-volcano is even BIGGER than scientists thought - 11th Apr 2011

(Image) - The first large-scale picture of the electrical conductivity in the Yellowstone National Park plume, showing the volcanic plume of partly molten rock that feeds the super-volcano. Yellow and red indicate higher conductivity, while green and blue indicate lower conductivity.

The gigantic underground plume of hot and partly molten rock that feeds the world's largest super-volcano is even bigger than previously thought, according to a new study.

Scientists made the first large-scale picture of the electrical conductivity in the Yellowstone National Park plume and discovered that it appears larger than in earlier images made with earthquake waves.

Researcher Professor Robert Smith, from the University of Utah, said: 'It's a totally new and different way of imaging and looking at the volcanic roots of Yellowstone.'

In a December 2009 study, Professor Smith used seismic waves from earthquakes to make the most detailed seismic images yet of the 'hotspot' plumbing that feeds the Yellowstone volcano.

Seismic waves move faster through cold rock and slower through hot rock. Measurements of seismic-wave speeds were used to make a three-dimensional picture, quite like X-rays are combined to make a medical CT scan.

The 2009 images showed the plume of hot and molten rock dips downward from Yellowstone at an angle of 60 degrees and extends 150 miles west / north-west to a point at least 410 miles under the Montana-Idaho border – as far as seismic imaging could 'see'. Read More