BEIJING, Sept. 27 (UPI) -- A volcano on the border of China and North Korea is showing signs of increasing activity and could erupt in the next few decades, Chinese researchers say.
A massive eruption of Changbaishan around 1,100 years ago spread ash and volcanic gases for 30 miles and left a 3-mile-wide crater atop the volcano, scientists said.
Three smaller eruptions have occurred since then, the most recent in 1903, they said.
Seismic activity, ground deformation and gas emissions recorded in a period of heightened activity from 2002 to 2006 suggests the magma chamber beneath the volcano is growing.
This activity suggests an explosion could occur in the next couple of decades, researchers said.
"We need to upgrade our current monitoring system in order to be able to meet the need for the early warning system for Changbaishan," Jiandong Xu, a vulcanologist at the China Earthquake Administration in Beijing, told OurAmazingPlanet.
Of the dozen or so volcanoes located in mainland China Changbaishan is the most likely to experience an eruption with potential catastrophic effects, Xu said.