1,000 degree C water tank under Bolivian volcano

A water reservoir with a volume of about 1.5 km3, located 15 km deep under the Uturuncu volcano, Bolivia, can conduct electricity and trigger volcanic eruptions.

A 1,000-degree Celsius water tank lies 15 kilometers below the Uturuncu volcano in Bolivia. Photo: Michael Sayles.

A research team from the University of Bristol, UK, has just discovered a water reservoir located 15 km deep under the Uturuncu volcano, Bolivia, Science Alert reported.

After careful examination, they concluded that the volume of water in the tank was about 1.5 cubic kilometers, equivalent to the volume of water in Lake Superior - the largest and deepest of the Great Lakes in North America and the third largest in the world.

The pool, called the Altiplano-Puna lava mass, is hotter than 1,000 degrees Celsius and is mixed with molten rock. This could make the volcano more prone to eruptions. In addition, the Altiplano-Puna lava mass can conduct electricity and appears to slow down seismic waves, unlike the surrounding lava that is not mixed with water.

To understand how it works, the team mixed 500,000-year-old volcanic rocks with water in the lab in an environment similar to that found 15 kilometers below Earth’s surface. They calculated that about 8-10 percent of the water was dissolved in the molten silicate.

"Ten percent of the mass of dissolved water means one water molecule combined with three silicate molecules. This is an unusually large water fraction that helps explain the excellent conductivity of this silicate liquid," said Fabrice Gaillard, from the University of Orleans in France, one of the researchers.

The team is not yet able to explain the role of the conductivity or how it affects volcanic eruptions. They now plan to investigate whether the unusual conductivity is a sign of secret reservoirs of water deep under other large volcanoes. If this is true, the team hopes to figure out how they cause their volcanoes to erupt, which could help them better predict when they will erupt.

According to VNE