London, Dec 12 : The supervolcano that lies beneath Yellowstone National Park in the US is even more colossal than previously thought, according to scientists.

A study shows that the magma chamber is about 2.5 times bigger than earlier estimates suggested.

A team found that the cavern stretched for more than 55 miles and contained 200-600 cubic km of molten rock, the BBC reported.

Prof Bob Smith , from the University of Utah, said that they'd been working there for a long time, and they always thought that it was be bigger but the finding was astounding.

Researchers used a network of seismometers situated around the park to map the magma chamber. (ANI)