Mega-eruption of Mount Sinabung awaited

As a mega-eruption is awaited, pyroclastic flows -- avalanche-like hot ash, rocks and gas -- have been rushing down the sides of Mount Sinabung in the Indonesian island of Sumatra. These pyroclastic flows can cascade down a volcano as fast as 60 miles per hour. And temperatures can soar above 932 degrees Fahrenheit, according to the USGS.

Pyroclastic flow in the southeast just hours ago. Photo by Mbah Lewa

Sinabung volcano in Northern Sumatra, Indonesia, is only 35 kilometers from the Toba volcano whose super-eruption, according to scientists, put mankind on the brink of extinction almost 70,000 years ago by causing a “nuclear winter,” which could have lasted several years.

"The growing size of the lava dome is very unstable," said government volcanologist Surono. That means there is a threat of a more powerful eruption, which could be accompanied by pyroclastic flows. This is the type of volcanic events which destroyed ancient Pompeii. 

The Indonesian archipelago consists of more than 13,000 islands and more than 75% of Indonesian residents live within 62 miles of volcanoes that have had some activity during the last century.