Eruption of Mount Merapi Still Possible

Villagers living on Mount Merapi's slopes watched as it spit out searing clouds of smoke and lava Monday amid warnings a large eruption was still possible in the aftermath of Indonesia's powerful earthquake.

Activity the volcano has increased since Saturday's earthquake, with hot clouds spewed out an average of 150 times a day, compared with 50 times before, said Subandriyo, chief of the Merapi volcanology and monitoring office.

The rumbling volcano expelled lava and hot clouds Monday morning, sending debris tumbling 2 1/2 miles down the mountain, he said.

"The earthquake has caused instability in the lava dome," said Subandriyo, who like many Indonesians uses only one name. "There is still a chance that a big eruption might occur."

Mount Merapi, which means "Fire Mountain," is one of the world's most active volcanos and has erupted scores of times in the last 200 years, often with deadly results.

The 9,800-foot volcano has been rumbling and spewing smoke and lava for weeks. Residents in the danger zone were ordered to evacuate earlier this month, but scores have remained, and say its latest activity has done little to change their minds.

"For us, life is going on as usual. This morning I tended the crops, some corn plants, and now I'm hauling grass to feed my cows," said Bardi as he headed down the mountain with a mound of grass. "I'm not afraid of Merapi."

Chew Soon Hoe, an associate professor of engineering geology at the National University of Singapore, said Merapi's renewed activity and the earthquake are related. Both are in the same subduction zone — the area where one tectonic plate slides under another plate — along a boundary between the Euro-Asia plate and the India-Australia plate, he said.

"This ocean plate ... is the cause of the recent earthquake and volcanic activity in Indonesia," Chew said. "Because it is very near, the energy released by the quake will accelerate or perturb the activity of the volcano."

David Booth, a seismologist with the British Geological Survey, disagreed, saying the quake would not necessarily cause the volcano to erupt. He said the plates that shifted to cause the earthquake did not necessarily open cracks in the surface that would be needed to cause a volcanic eruption.

"Volcanoes are all about creating pathways for the magma to move up to the surface," Booth said in a telephone interview. "It's like a lemonade bottle having been shaken. There is enormous pressure there. But if there isn't a pathway to the surface, then the pressure will stay contained."