What Makes Indonesia A Hot Spot On the Ring of Fire?

  • Share
  • Read Later

A volcano erupted on Indonesia’s most populated island, sending a huge plume of ash and sand 17 km (10 miles) into the air while triggering the evacuation of more than 100,000 people. The Indonesian archipelago lies atop one of the most seismically active zones of the earth, according to the USGS, and this is yet another instance of the “ring of fire” venting its furies.

Why is this region such a hotbed of volcanic activity?

The volcanoes prevalent in Indonesia’s Sunda Volcanic Arc “are the most common and the most dangerous,” says William Menke, Professor of Earth and Environmental Sciences at Columbia University. These volcanoes generate the planet’s most violent eruptions because they sit on subduction zones—where the continental crust and oceanic crust dive one under the other.

“They’re dangerous because lava is unusually high in steam, and it makes for very explosive eruptions,” says Menke. Contrary to popular belief, relatively few deaths are caused by lava in volcano eruptions, says Menke, because lava usually flows like a river. But in cases like Mount St. Helens in the United States or the one in Indonesia, “the biggest cause for fatalities are explosions of huge amounts of material into the air that come racing down the mountain like an avalanche.”

According to Menke, there are about 3,000 volcanoes in the world (at any one time 20 are erupting). Out of those, about 100 are in Indonesia.