On the densely populated island of Java on the east side of the island, one can see the largest mud volcano in the world. It is called the Sidoarjo mudflow or Lusi mudflow (known in Indonesian as Lumpur Lapindo - "lumpur" means mud). As a mud volcano, instead of spewing out molten rock, it ejected water and clay.

The mysterious Boiling River in the Amazon Rainforest in Peru was also feared to be the result of a manmade drilling disaster, but it turned out to be a very unusual natural phenomenon. Bali is much more than beaches, and Indonesia is much more than Bali. Take the time to explore the many things Indonesia has on offer (including the iconic Komodo Dragons of Komodo Island).

UPDATE: 2023/02/04 16:18 EST BY AARON SPRAY

What To Know About Mud Volcanoes

Mud volcanoes are not true volcanoes, but they are still spectacular. This article was expanded with more information about what a mud volcano is and what causes it. Indonesia is a very large country will some regular attractions (like tropical beaches) and some very unusual attractions (like mud volcanoes).

Eruption And Debated Cause Of The Sidarjo Mud Volcano

Sidoarjo first erupted in 2006 and has been a humanitarian and ecological disaster. It was the result of a blowout of a natural gas well from drilling in the area.

  • Date: First Erupted in 2006
  • Peak Flow: 180,000 Cubic Meters Of Mud Per Day

The site was previously a rice paddy, but the eruption cleaved the paddy open with the steaming mud. It covered an area twice the size of Central Park.

  • "Lusi": Alternative Name and A Contraction Of its Indonesian Name "Lumpur Sidoarjo"

There are two competing theories for the cause of the eruption. Some contend that it was set off by an earthquake, but most think a company drilling for natural gas is to blame. In a report in the journal Nature Geoscience, the researchers said that they were 99% sure that the drilling company caused the disaster.

Proponents of the other hypothesis point out that just 2 days before the eruption a 6.3 magnitude earthquake struck some 150 miles west of the drill site and could be to blame.

It is thought that even if the flow becomes so small it no longer needs management, it will likely be a geological feature for centuries.

Impact And Damage of the Mud Flow

At its peak, the mud volcano spewed up to some 180,000 cubic meters (or 240,000 cubic yards) of mud per day)but that slowed down massively over the next few years. Since 2008 the mudflows have been largely contained by levees.

It is expected that the flow will continue for another 25 to 30 years according to some earlier estimates. But NASA stated in 2019 that the best estimates say it is likely to continue for another 8 to 18 years.

In the wake of the baking mud, road, homes, and factories disappeared. It is thought that 20 people died in the disaster, with another 40,000 displaced.

  • Displaced: It Has Displaced Over 40,000 People
  • Villages: It Has Destroyed 15 Villages

Related: Abandoned Detroit: The Largest Automotive Plant In The World

The Sidoarjo Mudflow Today

Writing in 2019 NASA Earth Observatory noted

"More than a decade later, the Lusi mudflow continues on the Indonesian island... It has become one of the most dramatic and damaging eruptions of its type. Some villages have been buried by layers of mud 40 meters (130 feet) thick. The mud, which has a consistency similar to porridge, pours constantly from Lusi’s main vent."

They say that every 30 or so minutes surges in the flow send plumes of water vapor, carbon dioxide, and methine tens of meters into the air. Large volumes of the mud are flushed into the Porong River which then flows east toward the Bali Sea.

  • Levees: Now The Mud is Contained in A Network of Earthen Levees, Retention Ponds, and Distribution Channels

It was reported in June 2021 in The Jakarta Post the mud volcano is continuing to erupt. As it is in an urban area people are living mere meters from the embankment that contains the mudflow. Those people have to live with the smell and fumes of the eruption. Many have developed respiratory problems from inhaling the polluted air every day.

Sometimes the embankment cracks, and heavy flows of mud seep through. Some locals have had their houses submerged in the mud up to their waists. Some of the surrounding lands are sinking as a result of the disaster.

Related: Check Out These Abandoned Tube Stations In London

Visiting The Sidarjo Mud Volcano

According to Darktourism.com, one can see the mudflow from the memorial monument art installation.

They also go on to say that locals actually welcome foreign tourists as they can earn money from them by offering tours of the mud volcano. For many locals has been difficult to earn money or even plant vegetables since the volcano damaged everything and some were only compensated with $105. They say:

"...foreign tourists, are actually welcome here, on the part of the locals at least. Some offer motorbike rides around the mudflats for a fee"

When going there one can get a view of the "vastness of the ugly expanse of nothing but mud almost to the horizon." One can see electricity pylons poking out of the nothingness of the mud/lake.

If one would like to actually go inside a volcano, one can actually go down into the Thrihnukagigur volcano in Iceland.

What Are Mud Volcanoes?

Mud volcanoes are formed when a mound of mud is heaved up through overlying sediments. Some of them are formed by hot springs are large amounts of gas and small amounts of water react with the rocks and form boiling mud. They are not volcanoes in the strictest sense of the word - they are not caused by lava and magma bubbling to the surface.

Some mud volcanoes occur only in oil field regions, and it is possible that some mud volcanoes have even been found on Mars.

Mud volcanoes can be small - only measuring 1 to 2 meters high and 1 to 2 meters wide, while others can be massive. The largest can measure as much as 700 meters high and 10 kilometers wide. When they are small, they are sometimes called mud-pots.

Around 1100 mod volcanoes have been identified on or near land but perhaps none have been as destructive as the Sidoarjo mudflow of Indonesia. It is arguably one of the most incredible volcanoes to tour around the world.

Another unique volcano found in Indonesia is the Blue Lava Volcano near Bali (and it's worth visiting).