May 31, 2008

The world's largest mud volcano that has been erupting continuously since 2006 is beginning to show signs of "catastrophic collapse", according to geologists who have been monitoring it and the surrounding area.

The volcano - named Lusi - has already devastated homes and businesses in Sidoarjo, East Java, Indonesia, displacing around 10,000 people and killing 14.

Now scientists say that the land near the central vent could sag by up to 146 meters in the next decade. In March, the scientists observed drops of up to 3 meters in one night. Most of the subsidence in the area around the volcano is more gradual, at around 0.1 centimeter per day.

"It is starting to show signs that the central part is undergoing a more catastrophic collapse," said Prof. Richard Davies, a geologist at Britain's Durham University.

"The fact that the whole area is collapsing means there are probably new faults forming. These faults are new pathways for fluids to seep up to the surface. We've never really seen a mud volcano develop so quickly."


The team have monitored the subsidence using fixed GPS stations which are able to record very accurate ground movements by communicating with satellites. They reported their results in the journal Environmental Geology.

Last year, the Indonesian authorities began a desperate plan to drop 2000 concrete balls into Lusi's central vent in an effort to stem the flow. Davies watched the operation, which went on for two months.

"What happened was they dropped them and never saw them again," he said. "It just gobbled them up."

Since it began spewing noxious mud and gasses on May 29, 2006, Lusi has blanketed an area of around 7 cubic kilometers, covering 10,426 houses, 35 schools, 65 mosques and one orphanage. The advancing mud is now contained behind human-engineered dikes.

The central collapse may be good news because it will make room for more mud at the surface and so take the pressure off the dikes, but subsidence around the submerged zone will have more impact on the local community.

A bridge that developed cracks has already had to be dismantled, railway tracks have been moved out of line and in November 2006, 13 people were killed in a gas blast caused by an underground pipe rupturing.

Davies does not believe there is any way to stop Lusi now. "I think now the system has become so big ... the plumbing system is so complex you couldn't hope to stop it."

Intellpuke: You can read this article by Guardian science correspondent James Randerson, reporting from Manchester, England, in context here: " target="_blank">www.guardian.co.uk/science/2008/may/29/volcano

Eruptions of mud. A mud volcano on the Indonesian island of Java has been spewing out thousands of cubic yards of mud a day since it was set off two years ago, probably when a nearby drilling operation punctured an aquifer. So much mud has poured out -- the flows have blanketed almost three square miles with 65feet of mud -- that the center of the mud volcano is collapsing, say researchers at Durham University in England and the Institute of Technology Bandung in Indonesia. G.P.S. and satellite data recorded between June 2006 and September 2007 showed that the area around the volcano, known as Lusi, had sunk been 0.5 to 15 yards per year. If the eruption continues for 3 to 10 years at the rates measured in 2007, the central part of volcano could sink 30 to 150 yards, the researchers said.

Photo: Richard Davies/Durham University

The censors are OUT, and I can't put pics in my file folder ..



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