The eruption was triggered by the Banjar Panji-1 exploration well drilling, which punctured a high-pressure hydrothermal system.
The mud flow initially submerged an area of roughly 7 square kilometers, necessitating the relocation of over 30,000 residents.
Scientific consensus indicates the mud is sourced from sedimentary rock layers nearly 3 kilometers below the surface.
The Lusi eruption is considered a 'sedimentary volcano' rather than a traditional magma-based volcano.
The site experiences constant vertical ground subsidence, with the land level dropping several meters since the eruption began.
Geologists estimate that at its peak, the volcano emitted up to 180,000 cubic meters of mud per day.
The mud is rich in minerals and trace elements, often analyzed by researchers for its unique chemical composition.
A series of concrete embankments, known as the 'mud dikes,' were constructed to prevent the flood from reaching the main arterial roads and railway lines.
The Lapindo Sidoarjo Mud Volcano, also known as Lusi, is the world's largest active mud volcano, triggered by a drilling incident on May 29, 2006. It continues to eject hot, pressurized mud, water, and gas from deep subsurface layers, creating an expansive landscape of solidified mud flats. The eruption forced the abandonment of multiple villages, including Renokenongo and Siring, effectively burying them under meters of sediment. The site is a significant geological study area for experts monitoring volcanic activity and subsidence. Visitors can observe the sprawling, gray lunar-like terrain from vantage points constructed along the levees built to contain the flow. The active vent region is restricted, but the surrounding perimeter offers a stark view of the impact on the local geography. The mud is characterized by high salinity and the emission of methane gas, contributing to its ongoing instability. The site remains a powerful example of human-induced geological change in East Java.
From the top of the embankment dikes looking toward the center of the flow.
Wear sturdy, closed-toe shoes as the terrain around the dikes can be dusty or muddy.
Bring a mask or buff if you are sensitive to dust or hydrogen sulfide odors.
Stay strictly within marked designated observation areas for safety.
Do not attempt to walk onto the soft, central mud flats as the surface is unstable and potentially dangerous.
Respect the restricted zones; these areas are fenced off due to active geological hazards and potential instability.
