Heavy rains in Indonesia over the weekend triggered flash floods and sent torrents of cold lava tumbling down a volcano and spilling into towns, killing at least 37 people, officials said.
Hours of rain Saturday evening washed volcanic rocks and ash onto Mount Marapi, an active volcano on the island of Sumatra, and into homes in nearby towns. These mudflows are known as lahars in Indonesian, which translates to cold lava. The rain also caused a nearby river to overflow.
A moving lahar looks like a “wet concrete slurry” and a large lahar can crush, bury or carry away almost anything in its path, including buildings, bridges and roads, according to the United States Geographic Survey.
Lahars, which can also be triggered by landslides and volcanic eruptions that melt snow and ice, can quickly grow in size and speed as they rush down volcanoes, according to the American agency website. Some grow to more than 10 times their original size, incorporating more debris and water as they descend, and can exceed speeds of 120 miles per hour.
Four areas of West Sumatra suffered severe damage over the weekend, with nearly 200 homes flooded, according to Indonesia’s disaster agency. In one area, Agam, 159 people were evacuated, the agency said. said. Some floods left mud deposits high enough to reach an adult’s calves. said.
As of Sunday evening, 37 residents had been killed and 17 others were missing, the agency said.
