Drilling caused Indonesian mud volcano

WASHINGTON (Reuters) - Drilling of a gas exploration well, and not an earthquake, set off a volcano that has been spewing boiling mud for two years and has displaced more than 50,000 people on the Indonesian island of Java, experts said on Monday.

Records kept by oil and gas company Lapindo Brantas during the drilling of a gas exploration well called Banjar-Panji-1 show specific incidents that could have triggered the disaster, the international team of experts said.

"We are more certain than ever that the Lusi mud volcano is an unnatural disaster and was triggered by drilling the Banjar-Panji-1 well," said Richard Davies, a professor of earth sciences at Britain's Durham University.

"We show that the day before the mud volcano started, there was a huge 'kick' in the well, which is an influx of fluid and gas into the wellbore," Davies said in a statement.

"We show that after the kick, the pressure in the well went beyond a critical level. This resulted in the leakage of the fluid from the well and the rock formations to the surface -- a so-called underground blowout. This fluid picked up mud during its ascent, and Lusi was born."

The team of British, American, Indonesian and Australian scientists, writing in the journal Earth and Planetary Science Letters, said this pressurized fluid fractured the surrounding rock. Mud spurted out of cracks instead of the wellhead.

"There is not a hope on Earth they are going to stop it now," said the University of California Berkeley's Michael Manga, who worked on the study.

"You can plug up a hole, but if you try to plug a crack, stuff just flows around the plug, or the crack gets bigger. The well now has no effect on the erupting mud, it was just the trigger that initiated it."

MILLIONS IN DAMAGE