A two-year-old mud volcano altering the landscape of eastern Java is not the result of nature, but of a human mishap, according to a study by geophysicists. The volcano, which oozes muck instead of lava and has sent 30,000 people packing, resulted from an underground blow-out from a natural-gas drill rig, according to the report. The drilling company overseeing the operation argued that an earthquake some 155 miles away triggered the event.
Eight months after the eruption began, British geophysicist Richard Davies published a study questioning the earthquake hypothesis. In this latest analysis his team attributes the cause to the lack of a well casing that should have lined the lowest 5,700 feet of the local gas well. A steel casing would have formed a protective wall around the hole, significantly reducing the risk that high-pressurized fluids in the surrounding rock would flow up to the surface, gathering up muck along the way. The mud volcano, named Lusi, is spilling some 130,000 cubic yards of gunk a day into the countryside and could form a crater 500 feet deep. The results appear in this week’s Earth and Planetary Science Letters.