Gas drilling guilty of mud volcano eruption?

Contradictory theories about the cause of the Indonesian mud disaster

Mud Volcano in the USA © SR Brantley / USGS
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For 14 months he spits mud almost continuously - the mud volcano Lusi in the east of Java. And about the same amount of time scientists argue about the cause of the outbreak. While some consider an earthquake to be the trigger, now an American researcher has once again arrested man as the cause. Guilt, according to the researcher in an article published in Science Direct, is exploration drilling.

Since its first eruption on May 29, 2006, the activity of Lusi, a mud volcano near Surabaya, the second largest city in Indonesia, has not stopped. Every day, it spits out around 150, 000 cubic meters of sludge, and the ejection now covers more than ten square kilometers. According to authorities estimates, 20, 000 to 30, 000 people have since been evacuated, their homes and workplaces destroyed. But what is the cause of this never-ending activity? Exactly this question prevails so far disagreement in the research community.

Scientists at the University of Oslo had published a study in February, where they saw an earthquake, which occurred two days before the first eruption of the volcano in the region, as a trigger. But Richard Davies, a professor of Earth Sciences at Durham University, refutes it with a very different theory: his view and results suggest that activity at a nearby well is the cause. Here, the Indonesian oil and gas company Lapindo Brantas brought down a test well.

Bursting rock strata

"There were several problems with the exploration well before the mud volcano erupted, " explains Davies. "But only when they took out the drill head did they suck gas and water into the well. We calculated that this influx had produced a critical increase in the pressure in the hole that was sufficient to burst the rock layers underground. "

In the opinion of the researcher, however, it is unlikely that the Yoyakarta earthquake played a crucial role in the development of the mud volcano. "We keep in mind that the outbreak was most likely triggered by downhole activity. There is no reason to try to trigger an earthquake, "Davies said in his paper. display

(Durham University, 01.08.2007 - NPO)