Scientists at Rutgers University recently discovered the large mass of boiling hot rock that stretches across Massachusetts, Vermont and New Hampshire.
And it is believed it will eventually lead to a volcanic eruption as the magma nears the surface.
Vadim Levin, a professor at Rutgers' Department of Earth and Planetary Sciences, said: “The upwelling we detected is like a hot air balloon, and we infer that something is rising up through the deeper part of our planet under New England.
"It is a very large and relatively stable region, but we found an irregular pattern with rather abrupt changes in it.
“The bad news is, it's going to erupt.”
But Professor Levin said the eruption won’t happen for “a few million years”.
“The good news is, it's going to erupt a few million years from now,” he said.
But despite the low risk, the team is still trying to understand where the magma is coming from.
He added: “Nevertheless, the formation may challenge existing theory on the geological structure of New England, generally thought to be a stable and predictable formation.
“We did not expect to find abrupt changes in physical properties beneath this region and the likely explanation points to a much more dynamic regime underneath this old, geologically quiet area."
