Mud volcano floods Java

Earth News
Disaster-plagued Indonesian island faces new threat
Aug 29, 2006

What has happened?
For 3 months a sea of hot mud has been gushing from the ground in Sidoarjo, East Java, 35 kilometres south of Indonesia's second largest city, Surabaya. The steaming mud pool is growing at an estimated 50,000 cubic metres a day, accompanied by hydrogen sulphide gas, and now reportedly covers more than 25 square kilometres. The flow has not yet been stopped; thousands of people have lost their homes.

How bizarre... has this sort of disaster happened before?
The Sidoarjo disaster is an example of a 'mud volcano'. Mud and gas accumulates when sea sediments are trapped in subduction zones, where one tectonic plate slides under another, and can erupt out of volcanic cones or simply from a crack in the ground. Mud volcanoes have burst on every continent, but are abundant in the South Caspian region (offshore and onshore Azerbaijan) and offshore Indonesia in the East Java Basin.But the Sidoarjo mud volcano is rather unusual. It's huge. And, says Sam Rice, a geologist with the Cambridge Antarctic Shelf Programme, UK, reports of the mud eruption suggest that it is a hybrid between typical mud volcanoes and hydrothermal vents. The mud is of an unusually high temperature (60 °C) and contains enormously high concentrations of hydrogen sulphide gas. This suggests that some kind of volcanic, hydrothermal activity is going on at the same time.
{Photo Above: Residents carry their belongings through mud as they evacuate their homes in east Java.}

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